- /3 pages
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- blog/2,288 pages
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Engine coolant temperature sensors – a closer look – owenduffy.net
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Phase nonsense – owenduffy.net
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RK2672AM – calibration – owenduffy.net
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Diagnosis of engine coolant temperature gauge issue with a certain vehicle – owenduffy.net
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A handy 230VAC 10A inline power meter based on an inexpensive module from eBay – owenduffy.net
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Baofeng UV-5R battery and charging experience – owenduffy.net
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Comment on KN5L on balun CMRR – series through impedance fixture – owenduffy.net
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Comment on KN5L on balun CMRR – two wire line example – owenduffy.net
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Comment on KN5L on balun CMRR – coax example – owenduffy.net
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Baofeng BF-T1 (BF-9100) – initial impressions – owenduffy.net
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Comparing sensitivity figures of an AM receiver and SSB receiver – owenduffy.net
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Low power Guanella 1:1 balun with low Insertion VSWR using a Fair-rite 2×2631540002 – measurement of Zcm – owenduffy.net
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Low power Guanella 1:1 balun with low Insertion VSWR using a Fair-rite 2843009902 binocular – measurement of Zcm – owenduffy.net
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Baofeng BF-F8HP battery and charging experience – owenduffy.net
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Baofeng GT-5TP battery and charging experience – owenduffy.net
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Low power Guanella 1:1 balun with low Insertion VSWR using a Fair-rite 2843009902 binocular – design workup – owenduffy.net
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Review of MXITA SMA-8 #2 – owenduffy.net
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Return Loss Bridge – some woolly thinking – a Simsmith model of a reflection bridge – owenduffy.net
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Return Loss Bridge – some woolly thinking – owenduffy.net
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Low power Guanella 1:1 balun with low Insertion VSWR using a pair of Fair-rite 2631540002 suppression sleeves – design workup – owenduffy.net
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Transmission line filter for a field day station – implementation – owenduffy.net
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On Insertion Loss – owenduffy.net
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Transmission line filter for a field day station – designs – owenduffy.net
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Measuring OC and SC transmission line sections – owenduffy.net
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Estimating transmission line Zo – λ/8 method – nanoVNA – success – owenduffy.net
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A magnetics review of the VK3AMP Sontheimer directional coupler – owenduffy.net
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Basic measurements of the VK3AMP Sontheimer directional coupler for a N2PK wattmeter – owenduffy.net
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Failure estimating transmission line Zo – λ/8 method – nanoVNA – Smith chart perspective – owenduffy.net
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Failure estimating transmission line Zo – λ/8 method – nanoVNA – owenduffy.net
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Select a ferrite core material and sufficient primary turns for a low InsertionVSWR 50Ω broadband RF transformer – comparison of measured and predicted – owenduffy.net
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Fair-rite’s ‘new’ #43 permeability data (2020) – owenduffy.net
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A Smith chart should go round in circles – owenduffy.net
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Surely there cannot be more forward power than the transmitter makes? – owenduffy.net
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Select a ferrite core material and sufficient primary turns for a low InsertionVSWR 50Ω broadband RF transformer – nanoVNA – loss components graph – owenduffy.net
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A DIY thermostat based on the MS1230A controller – owenduffy.net
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Select a ferrite core material and sufficient primary turns for a low InsertionVSWR 50Ω broadband RF transformer – nanoVNA – owenduffy.net
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Phase of s11 and Z – owenduffy.net
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The quarter sized G5RV with hybrid feed – owenduffy.net
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A thermostatically controlled pot for waxing leg hold traps – owenduffy.net
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The devil is in the detail… – owenduffy.net
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Optimal common mode impedance of a common mode choke – owenduffy.net
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Fox flasher MkII update 2/2021 – owenduffy.net
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Improving ‘s21 shunt-through’ measurement of low impedances – more detail – owenduffy.net
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Improving ‘s21 shunt-through’ measurement of low impedances – owenduffy.net
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Antenna system resonance and the nanoVNA – owenduffy.net
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Improving ‘s21 series-through’ measurement of high impedances – more detail – owenduffy.net
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Improving ‘s21 series-through’ measurement of high impedances – owenduffy.net
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IoT – owenduffy.net
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The fine print – owenduffy.net
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nanovna – owenduffy.net
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owenduffy.net – Page 2 – Mostly electronics…
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owenduffy.net – Page 138 – Mostly electronics…
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April 2021 – owenduffy.net
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March 2021 – owenduffy.net
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February 2021 – owenduffy.net
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January 2021 – owenduffy.net
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December 2020 – owenduffy.net
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November 2020 – owenduffy.net
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October 2020 – owenduffy.net
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September 2020 – owenduffy.net
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August 2020 – owenduffy.net
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July 2020 – owenduffy.net
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June 2020 – owenduffy.net
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May 2020 – owenduffy.net
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April 2020 – owenduffy.net
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March 2020 – owenduffy.net
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February 2020 – owenduffy.net
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January 2020 – owenduffy.net
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December 2019 – owenduffy.net
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November 2019 – owenduffy.net
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October 2019 – owenduffy.net
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September 2019 – owenduffy.net
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August 2019 – owenduffy.net
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July 2019 – owenduffy.net
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June 2019 – owenduffy.net
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May 2019 – owenduffy.net
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April 2019 – owenduffy.net
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March 2019 – owenduffy.net
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February 2019 – owenduffy.net
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January 2019 – owenduffy.net
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December 2018 – owenduffy.net
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November 2018 – owenduffy.net
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October 2018 – owenduffy.net
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September 2018 – owenduffy.net
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August 2018 – owenduffy.net
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July 2018 – owenduffy.net
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June 2018 – owenduffy.net
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May 2018 – owenduffy.net
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April 2018 – owenduffy.net
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March 2018 – owenduffy.net
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February 2018 – owenduffy.net
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January 2018 – owenduffy.net
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December 2017 – owenduffy.net
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November 2017 – owenduffy.net
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October 2017 – owenduffy.net
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September 2017 – owenduffy.net
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August 2017 – owenduffy.net
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July 2017 – owenduffy.net
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June 2017 – owenduffy.net
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May 2017 – owenduffy.net
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April 2017 – owenduffy.net
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March 2017 – owenduffy.net
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February 2017 – owenduffy.net
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January 2017 – owenduffy.net
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December 2016 – owenduffy.net
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November 2016 – owenduffy.net
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October 2016 – owenduffy.net
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September 2016 – owenduffy.net
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August 2016 – owenduffy.net
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July 2016 – owenduffy.net
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June 2016 – owenduffy.net
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May 2016 – owenduffy.net
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April 2016 – owenduffy.net
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March 2016 – owenduffy.net
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February 2016 – owenduffy.net
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January 2016 – owenduffy.net
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December 2015 – owenduffy.net
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November 2015 – owenduffy.net
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October 2015 – owenduffy.net
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September 2015 – owenduffy.net
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August 2015 – owenduffy.net
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July 2015 – owenduffy.net
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Nichols: The Two Bird Experiment – a Simsmith model – owenduffy.net
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Calculate Loss from s11 and s21 – convenient online calculator – owenduffy.net
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Measure transmission line Zo – nanoVNA – PVC speaker twin – owenduffy.net
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Measure transmission line Zo – nanoVNA – CCS RG6 – owenduffy.net
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Nichols: The Two Bird Experiment – owenduffy.net
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Conductors for a Guanella 1:1 balun – discussion – owenduffy.net
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The requisite knowledge does not come in the box – owenduffy.net
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nanoVNA – touch screen problems – owenduffy.net
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nanoVNA – measure Transmission Loss – example 5 – owenduffy.net
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Low power Guanella 1:1 balun with low Insertion VSWR using a pair of Jaycar LF1260 suppression sleeves – owenduffy.net
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owenduffy.net – Page 137 – Mostly electronics…
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High voltage test of a couple of PTFE insulated silver plated copper wires – owenduffy.net
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An example and explanation of unexpected common mode choke flashover – owenduffy.net
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Mornhinweg ferrite core measurements – #61 – owenduffy.net
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Using complex permeability to design with Fair-rite suppression products – owenduffy.net
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Black body emissivity of ferrite core material – owenduffy.net
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Calculate ferrite cored inductor – rectangular cross section – enhancement – chamfered corners – owenduffy.net
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MH1210A, MH1230A operating instructions – owenduffy.net
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Jaycar LO1238 ferrite core – owenduffy.net
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Mornhinweg ferrite core measurements – #31 – owenduffy.net
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Gauss based ferrite core loss – owenduffy.net
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Disturbing the thing being measured – coax line – owenduffy.net
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Amidon’s method of rating ferrite inductors and transformers – owenduffy.net
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owenduffy.net – Page 136 – Mostly electronics…
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Quantifying performance of a simple broadcast receive system on MF – owenduffy.net
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nanoVNA – measure Transmission Loss – example 4 – owenduffy.net
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KL7AJ on the Conjugate Match Theorem – analytical solution – Simsmith – owenduffy.net
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nanoVNA – measure Transmission Loss – example 3 – owenduffy.net
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nanoVNA – measure Transmission Loss – example 2 – owenduffy.net
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owenduffy.net – Page 135 – Mostly electronics…
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nanoVNA – measure Transmission Loss – example 1 – owenduffy.net
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Magnitude and phase of V2/V1 for a 180° transmission line section – owenduffy.net
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Antennas – Page 2 – owenduffy.net
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Magnitude and phase of I2/V1 for a 90° transmission line section – owenduffy.net
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Magnitude and phase of V2/V1 for a transmission line section – owenduffy.net
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?feed=rss2&cat=22
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Tuning electrical line length using phase of measured s21 – nanoVNA – owenduffy.net
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PERL vs Python pre / post processing NEC – owenduffy.net
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The j value – owenduffy.net
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Applying the RG6/U to a 40m Inverted V Dipole antenna – owenduffy.net
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On measuring antennas through integral halfwaves of transmission line – owenduffy.net
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On the measured phase of s11 in a matched system – owenduffy.net
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Applying the RG11A/U to a 40m Inverted V Dipole antenna – owenduffy.net
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144MHz beacon observation from Wellington NSW – 3 aircraft reflections – owenduffy.net
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Checkout of a roll of Commscope 4510404 CCS RG11A/U – Zoc, Zsc based MLL calculation – nanoVNA – owenduffy.net
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Steel as an antenna radiator – owenduffy.net
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Fox flasher MkII – owenduffy.net
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owenduffy.net – Page 134 – Mostly electronics…
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Checkout of a roll of Commscope 4510404 CCS RG11A/U – Zoc, Zsc based MLL calculation – owenduffy.net
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Checkout of a roll of Commscope 4510404 CCS RG11A/U – owenduffy.net
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A walkthrough of using a Rigexpert AA-600 to make a quick measurement of loss of a new roll of CCS RG11 – owenduffy.net
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A model of current distribution in copper clad steel conductors at RF – comparison with Severns 2000 – owenduffy.net
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High and low Z responses of a resonant / antiresonant shorted / open transmission line section – owenduffy.net
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KB1CKT measurement of a roll of RG6/U – owenduffy.net
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Loss of ladder line: copper vs CCS (Seminole 1320 vs 1321) – KN5L’s measurements – owenduffy.net
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Loss of ladder line: copper vs CCS (DXE-LL300-1C) – KN5L’s measurement 11/2020 – owenduffy.net
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A low cost two wire transmission line using high strength aluminium MIG wire and agricultural trellis clips – owenduffy.net
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owenduffy.net – Page 133 – Mostly electronics…
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RG6/U with CCS centre conductor – shielded twin study – why is it so lossy? – owenduffy.net
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nanoVNA – evaluation of a voltage balun – RAK BL-50A – owenduffy.net
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Loss of ladder line: copper vs CCS (DXE-LL300-1C) – revised for 25/07/2018 datasheet – owenduffy.net
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nanoVNA – evaluation of a voltage balun – W2AU 1:1 – owenduffy.net
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what-exactly-happens-to-the-signals-hitting-a-common-mode-choke? – owenduffy.net
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Some pretty woolly thinking about the operation of common mode chokes in antenna systems – owenduffy.net
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Active monopole + RTL SDR + RPi Spyserver experiment – owenduffy.net
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A 1:1 RF transformer for measurements – based on noelec 1:9 balun assembly – owenduffy.net
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The devil is in the detail – real world transmission lines and loss under standing waves – owenduffy.net
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The devil is in the detail – real world transmission lines and ReturnLoss – owenduffy.net
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4:1 current balun – review and fix – owenduffy.net
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owenduffy.net – Page 132 – Mostly electronics…
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Measurement of recent ‘FT240-43’ core parameters – owenduffy.net
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nanoVNA – RG6/U with CCS centre conductor MLL measurement – owenduffy.net
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RG6/U with CCS centre conductor – shielded twin study – owenduffy.net
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nanoVNA – measuring cable velocity factor – demonstration – open wire line – owenduffy.net
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ESP32 WROOM32 – A possible fix for failure of auto-program facility – owenduffy.net
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Battery contact corrosion on digital calipers – owenduffy.net
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Working a common mode scenario – VK2OMD – voltage balun solution – owenduffy.net
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Working a common mode scenario – G3TXQ Radcom May 2015 – voltage balun solution – owenduffy.net
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Working a common mode scenario – G3TXQ Radcom May 2015 – owenduffy.net
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Photo Voltaic Array – unbelievable efficiency from Chinese sellers – owenduffy.net
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owenduffy.net – Page 131 – Mostly electronics…
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A dipole centre insulator from HDPE cutting board – owenduffy.net
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Windows 10 – sound device Signal Enhancements – owenduffy.net
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nanoVNA – experts on improvised fixtures – owenduffy.net
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Sydney harbour is a beautiful place – owenduffy.net
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Leaflet / OpenStreetMap map rendering on devices with tiny pixels – owenduffy.net
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Simsmith bimetal line type – revision #1 – owenduffy.net
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A model of current distribution in copper clad steel conductors at RF – capturing conductor curvature – owenduffy.net
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Distance to fault in submarine telegraph cables ca 1871 – the leap expanded – owenduffy.net
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owenduffy.net – Page 130 – Mostly electronics…
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Review of MXITA SMA-8 – owenduffy.net
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The ZS6BKW five band antenna – discussion of an NEC model – owenduffy.net
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Distance to fault in submarine telegraph cables ca 1871 – owenduffy.net
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An experimental propagation beacon on 144MHz – owenduffy.net
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nanoVNA – tuning stubs using TDR mode – owenduffy.net
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NEC sez… – owenduffy.net
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SDR# (v1.0.0.1732) – channel filter exploration – owenduffy.net
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A Smith chart view of EFHW transformer compensation – owenduffy.net
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A model of current distribution in copper clad steel conductors at RF – owenduffy.net
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Stacking of Yagis and antenna effective aperture – owenduffy.net
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Desk review of the AAA-1C as an active dipole antenna – owenduffy.net
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Small untuned loop for receiving – a design walk through #4 – owenduffy.net
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owenduffy.net – Page 129 – Mostly electronics…
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Noise figure of active loop amplifiers – the Ikin dynamic impedance method – owenduffy.net
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Noise figure of active loop amplifiers – some thoughts – owenduffy.net
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Small untuned loop for receiving – a design walk through #3 – owenduffy.net
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RG6/U with CCS centre conductor at HF – owenduffy.net
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Small untuned loop for receiving – a design walk through #2 – owenduffy.net
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Small untuned loop for receiving – a design walk through #1 – owenduffy.net
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Review of iFIX RT300M v2 LED tester – owenduffy.net
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Finding the electrical length of the branches of an N type T – #4 – owenduffy.net
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Loss of ladder line: copper vs CCS (DXE-LL300-1C) – owenduffy.net
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Finding the electrical length of the branches of an N type T – #3 – owenduffy.net
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Finding the electrical length of the branches of an N type T – #2 – owenduffy.net
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Finding the electrical length of the branches of an N type T – #1 – owenduffy.net
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Performance of a small transmitting loop with varying height – NEC-5.0 – owenduffy.net
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owenduffy.net – Page 128 – Mostly electronics…
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Adjustable plank refurbishment – owenduffy.net
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Calculation of impedance of a ferrite toroidal inductor – from first principles – owenduffy.net
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nanoVNA – measuring cable velocity factor – demonstration – coax – owenduffy.net
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nanoVNA – measuring cable velocity factor – owenduffy.net
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PllLdr application – ATTiny44 & AD9833 in Codan 6801 – owenduffy.net
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Arduino Nano – FT232RL test pin floats – owenduffy.net
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Small untuned loop for receiving – it’s not rocket science – owenduffy.net
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nanoVNA-H – Deepelec test jig – owenduffy.net
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YouLoop-2T and the self resonance bogey at MF/lowHF – owenduffy.net
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Oyster conversion – #2 – 24W – owenduffy.net
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Equivalent circuit of an antenna system – owenduffy.net
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owenduffy.net – Page 127 – Mostly electronics…
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LED plate analysis – 24W round plate with driver – owenduffy.net
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(How) does this balun work? (Tonna / F9FT balun for Yagis) – owenduffy.net
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Chinese R7s LED replacement – review – owenduffy.net
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AD9833 / PllLdr checkout – owenduffy.net
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STC-1000 firmware change – STC-1000B – owenduffy.net
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Antenna analyser – what if the device under test does not have a coax plug on it? – owenduffy.net
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144MHz propagation experiment – antenna – owenduffy.net
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Simsmith bimetal line type – owenduffy.net
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LED Driver measurement – #2 – owenduffy.net
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LED plate analysis – D44-22P-01 – owenduffy.net
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owenduffy.net – Page 126 – Mostly electronics…
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Rigexpert Antscope2 – v1.1.1 – owenduffy.net
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Rigexpert AA-600 N connector dimensions – owenduffy.net
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AIM4170 – de-embedding the feed line in remote measurement – a simple match – owenduffy.net
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AIM4170 – de-embedding the feed line in remote measurement – owenduffy.net
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LED lamp failure analysis – GU10 230VAC 7W – owenduffy.net
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(How) does this balun work? – owenduffy.net
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nanoVNA-H – measure ferrite transformer – Noelec balun – owenduffy.net
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Chinese LED ratings – LED plate drivers – owenduffy.net
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Chinese T8 LED 4′ tube teardown – owenduffy.net
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VSWR ripple – owenduffy.net
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Transformer loss from half return loss – owenduffy.net
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owenduffy.net – Page 125 – Mostly electronics…
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nanoVNA-H – another hardware fail – battery socket – owenduffy.net
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TKDMR TD2B LED tester review – owenduffy.net
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SND implications of variations on the untuned small loop at MF/lowHF – owenduffy.net
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U-BLOX LEA-6T GPS module – for experiments – owenduffy.net
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APRS duplicate removal – owenduffy.net
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Osram Substitube tear down – owenduffy.net
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Towards understanding the YouLoop-2T at MF/lowHF – owenduffy.net
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A transmission line 1:4 impedance transformer – owenduffy.net
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Small untuned loop for receiving – simple model with transformer – owenduffy.net
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nanoVNA-H – Port 1 attenuator for improved what??? – owenduffy.net
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Return Loss Bridge – some important details – owenduffy.net
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owenduffy.net – Page 124 – Mostly electronics…
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nanoVNA – promotion by cheats – owenduffy.net
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nanoVNA-H – woolly thinking on MLL measurement – owenduffy.net
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RG6 cladding thickness report – owenduffy.net
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nanoVNA-H – thinking laterally – owenduffy.net
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Chinese CH2 terminal block (CH1 CH3) – owenduffy.net
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Conversion of oyster luminaire to LED – owenduffy.net
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MFJ ATU hand effects on capacitor knobs – owenduffy.net
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nanoVNA-H – de-embedding the feed line in remote measurement – owenduffy.net
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WIA 4:1 current balun – further measurements – owenduffy.net
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4:1 current balun – identifying bad ones – owenduffy.net
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owenduffy.net – Page 123 – Mostly electronics…
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nanoVNA-H – Port 2 attenuator for improved Return Loss – owenduffy.net
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A common mode choke for a VDSL pair – LF1260 core – owenduffy.net
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nanoVNA-H – measuring an inductor – is it a no-brainer? – owenduffy.net
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Trial of prototype stand alone GPS logger – owenduffy.net
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ATUs and periodic maintenance – owenduffy.net
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Measuring balun common mode impedance â #3 – owenduffy.net
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Small common mode choke for analyser antenna measurements using 2843000202 (BN43-202) – owenduffy.net
-
nanoVNA-H – continuing USB-C repair – owenduffy.net
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NEC – vertical monopole ground wave study – owenduffy.net
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NEC – vertical monopole radiation resistance study – owenduffy.net
-
Milton Moore’s power supply test – owenduffy.net
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STC-1000 firmware change – owenduffy.net
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Current regulation dynamics of Atten APS3005S – owenduffy.net
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Power meter + dimmer – owenduffy.net
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owenduffy.net – Page 122 – Mostly electronics…
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An Arduino utility for the RW1990 rewriteable serial number touch memory – owenduffy.net
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4NEC2 – summary statistics discussion – owenduffy.net
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Programming a certain type of Chinese 315/433MHz EV1527 compatible remote relay – owenduffy.net
-
FT240-43 matching transformer for an EFHW – NEC model at 3.6MHz – owenduffy.net
-
Small efficient matching transformer for an EFHW – NEC model at 3.6MHz – owenduffy.net
-
Exploration of feasibility of ground wave comms on 80m VK2OMD-VK1EA – owenduffy.net
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LDF4-50A shield prep with simple hand tools – owenduffy.net
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nanoVNA-H – continuing USB-C woes #2 – owenduffy.net
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RF transmission lines – quite old art – owenduffy.net
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nanoVNA – VSWR in terms of 400Ω – owenduffy.net
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nanoVNA-H – measure ferrite transformer – owenduffy.net
-
Annual inspection of antenna reveals balun box issue – owenduffy.net
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Review of W8TEE, AC8GY STL (Radcom Feb 2020) – owenduffy.net
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owenduffy.net – Page 121 – Mostly electronics…
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Reinforcement of nanoVNA-H connectors – performance discussion – owenduffy.net
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Windowed ladder line – single core CCS 21% IACS – owenduffy.net
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Radcom Feb 2019 “cable balun” – comment on Radcom “The last word” letter – owenduffy.net
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W551 CCS windowed ladder line – a guide to low end loss – owenduffy.net
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nanoVNA-H – continuing USB-C woes – owenduffy.net
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Simsmith bimetal line type – a comparison around the first MLL minimum – owenduffy.net
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Measuring coaxial cable loss by reflection with a directional wattmeter – owenduffy.net
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Measuring coaxial cable loss by reflection with a VNA – owenduffy.net
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Measuring coaxial cable loss by transmission measurement with a directional wattmeter – owenduffy.net
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owenduffy.net – Page 120 – Mostly electronics…
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Measuring coaxial cable loss with a voltmeter – owenduffy.net
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Chinese wattmeter / power analyser fix – owenduffy.net
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Stub matching loss can bite you – owenduffy.net
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A thinking exercise on Jacobi Maximum Power Transfer #4 – owenduffy.net
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The transmitter matching problem – owenduffy.net
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owenduffy.net – Page 119 – Mostly electronics…
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Strength of reinforcement of nanoVNA-H connectors – owenduffy.net
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nanoVNA-H – recovery – owenduffy.net
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A thinking exercise on Jacobi Maximum Power Transfer #3 – owenduffy.net
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A thinking exercise on Jacobi Maximum Power Transfer #2 – owenduffy.net
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nanoVNA-H – rework of v3.3 PCB to v3.4? – owenduffy.net
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A thinking exercise on Jacobi Maximum Power Transfer – owenduffy.net
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nanoVNA-H – measure 40m low pass filter for WSPRlite flex – owenduffy.net
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RFPM2 – current probe – #3 – owenduffy.net
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nanoVNA-H – v3.3 USB problems – owenduffy.net
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A mount for the coax relay driver development prototype – owenduffy.net
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nanoVNA – measurement of two 920MHz LoRa antennas – owenduffy.net
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nanoVNA – that demo board and its U.FL connectors – owenduffy.net
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owenduffy.net – Page 118 – Mostly electronics…
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Coaxial Collinear – dielectric loading the outer conductor – owenduffy.net
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HanRongDa HRD-831 FM transmitter – configuration and review – owenduffy.net
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nanoVNA user post provides an interesting example for study #1 – owenduffy.net
-
Normalised RMS voltage of a full wave phase controlled power waveform – owenduffy.net
-
nanoVNA-H – measure 144MHz Yagi gain – planning / feasibility – owenduffy.net
-
Antennas – disturbing the thing being measured – open wire lines #6 – owenduffy.net
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Antennas – disturbing the thing being measured – open wire lines #5 – owenduffy.net
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Small efficient matching transformer for an EFHW – owenduffy.net
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Antennas – disturbing the thing being measured – open wire lines #4 – owenduffy.net
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Antennas – disturbing the thing being measured – open wire lines #3 – owenduffy.net
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Antennas – disturbing the thing being measured – open wire lines #2 – owenduffy.net
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Antennas – disturbing the thing being measured – open wire lines – owenduffy.net
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Soldering iron – temperature control failure – owenduffy.net
-
Implementation of G5RV inverted V using high strength aluminium MIG wire – impedance measurements – owenduffy.net
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owenduffy.net – Page 117 – Mostly electronics…
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RFPM2 – current probe – #2 – owenduffy.net
-
nanoVNA – a surfit of choices – owenduffy.net
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MFJ-1786 loop antenna – a study of the matching scheme – owenduffy.net
-
MFJ-1786 loop antenna – measurements and NEC-4.2 model at 10.1MHz – analysis tools – owenduffy.net
-
MFJ-1786 loop antenna – other models at 10.1MHz – owenduffy.net
-
Radcom Feb 2019 “cable balun” – owenduffy.net
-
Radcom Feb 2019 “cable balun” – a deeper look – owenduffy.net
-
MFJ-1786 loop antenna – measurements and NEC-4.2 model at 10.1MHz – owenduffy.net
-
nanoVNA-H – coax connectors – owenduffy.net
-
nanoVNA-H – supplied cables – owenduffy.net
-
owenduffy.net – Page 116 – Mostly electronics…
-
NEC model of figure 8 transmitting loop – owenduffy.net
-
nanoVNA-H – a summary of the experience so far – owenduffy.net
-
Acrylic plinth for small card modules – CNC router make – owenduffy.net
-
On the concept of that P=Pfwd-Prev – owenduffy.net
-
The system wide conjugate match stuff crashes out again – owenduffy.net
-
AD8310 module for HF current probe – owenduffy.net
-
nanoVNA-H – sweep of a coax line section with OC termination – owenduffy.net
-
nanoVNA-H – T-Check test – owenduffy.net
-
CNC6040 router project – cut of enclosure for grbl_ESP32 – owenduffy.net
-
nanoVNA-H – measure ferrite core permeability – owenduffy.net
-
owenduffy.net – Page 115 – Mostly electronics…
-
nanoVNA-H – measure equivalent core loss resistance – owenduffy.net
-
nanoVNA-H – a ferrite cored test inductor impedance measurement – s21 series vs s11 reflection – owenduffy.net
-
nanoVNA-H – Chinese junk? – owenduffy.net
-
nanoVNA-H – a ferrite cored test inductor – drilling down on a glitch – the fix – owenduffy.net
-
DfuSe – dependency on Visual C++ 2013 runtime – owenduffy.net
-
RFPM2 – current probe – owenduffy.net
-
nanoVNA-H – a ferrite cored test inductor – drilling down on a glitch – owenduffy.net
-
nanoVNA-H – standalone VHF antenna VSWR sweep – owenduffy.net
-
nanoVNA-H – mobile UHF antenna VSWR sweep – owenduffy.net
-
nanoVNA-H – a ferrite cored test inductor – owenduffy.net
-
nanoVNA-H – first experience – owenduffy.net
-
nanoVNA-H – occasional glitches in measured data – owenduffy.net
-
Series match for a half wave dipole – owenduffy.net
-
Rigexpert AA-600 reference plane – owenduffy.net
-
IoT – exploration of LoRa – part 3 – owenduffy.net
-
owenduffy.net – Page 114 – Mostly electronics…
-
nanoVNA MOD v3 – a first look – owenduffy.net
-
nanoVNA – a first plunge – owenduffy.net
-
SimSmith – looking both ways – an LNA design task – owenduffy.net
-
Transmitter / antenna systems and the maximum power transfer theorem – owenduffy.net
-
CNC6040 router project – test cut of a Jiffy box – owenduffy.net
-
owenduffy.net – Page 113 – Mostly electronics…
-
Walter Maxwell’s teachings on system wide conjugate matching – a SimSmith example – owenduffy.net
-
Cooking the books on VSWR – Bird43 indication – owenduffy.net
-
Cooking the books on VSWR – owenduffy.net
-
CNC6040 router project – spindle speed linearisation – using new grbl_ESP32 feature – owenduffy.net
-
CNC6040 router project – spindle speed linearisation – owenduffy.net
-
Noise Figure Y factor method calculator updated – owenduffy.net
-
Noise Figure – Equivalent Noise Bandwidth – owenduffy.net
-
nanovna-saver – a first look – owenduffy.net
-
Is it 290K or 293K? – owenduffy.net
-
Update for NFM software (v1.19.0) – owenduffy.net
-
Maximum acceptable receiver noise figure – derived from ITU-R P.372-13 guidance – owenduffy.net
-
Noise Figure measurement of a converter / transverter – owenduffy.net
-
owenduffy.net – Page 112 – Mostly electronics…
-
Optimum receive system noise figure for given ambient noise – Flex 6700 – owenduffy.net
-
Optimum receive system noise figure for given ambient noise – Flex 6600 – owenduffy.net
-
Minimum ambient noise level – ITU-R P.372-13 guidance – owenduffy.net
-
Franklin antenna – how does it work? – owenduffy.net
-
End Fed Half Wave matching transformer – 80-20m – LO1238 variant – owenduffy.net
-
S/N degradation is related to external noise level and receive system internal noise – owenduffy.net
-
owenduffy.net – Page 111 – Mostly electronics…
-
End Fed Half Wave matching transformer – 80-20m – 2xFT240-43 variant – owenduffy.net
-
Post post implementation review R134a replaced with HyChill Minus 30 – owenduffy.net
-
Online calculator of ferrite material permeability interpolations – more detail – owenduffy.net
-
Holux web site missing / offline, Holux ezTour crippled – owenduffy.net
-
OpenLog for TinyTrak – inline DE9 adapter – owenduffy.net
-
Diagnosing a possible antenna problem by comparison with a baseline – owenduffy.net
-
Refurbishing the push button in action cam cases – owenduffy.net
-
Matching a 5/8λ ground plane – a single stub tuner example – owenduffy.net
-
Trapped dipole – owenduffy.net
-
owenduffy.net – Page 110 – Mostly electronics…
-
Designing with binocular ferrite cores – published Al values – owenduffy.net
-
Designing with binocular ferrite cores – Σ(A/l) – owenduffy.net
-
Do Distortionless Lines exist? – owenduffy.net
-
Comparison of BN43-202 / 5t with BN73-202 / 2t for rx only on low HF – small broadband RF transformer – 50:200Ω – owenduffy.net
-
Transmission lines: departure from ideal Zo – owenduffy.net
-
Basic programming jig for STC15F104E and STC15F204E chips #3 – owenduffy.net
-
XH plug savers on the STC U8W & U8 programmer – owenduffy.net
-
Garden hose couplers – there has to be a better way – owenduffy.net
-
RF transformer design with ferrite cores – saturation calcs – owenduffy.net
-
RF transformer design with ferrite cores – initial steps – owenduffy.net
-
An online expert on the unsuitability of #43 for HF UNUNs – owenduffy.net
-
Speaker tick generator #2 (for polarity testing) – owenduffy.net
-
Fox flasher MkII update 7/2019 – owenduffy.net
-
owenduffy.net – Page 109 – Mostly electronics…
-
Basic programming jig for STC15F104E and STC15F204E chips – owenduffy.net
-
From lossless transmission line to practical – Zo and γ – owenduffy.net
-
SimSmith example of VSWR assessment – owenduffy.net
-
ESP01S IoT – Thingspeak GET submission – owenduffy.net
-
On working with complex Zo – owenduffy.net
-
ESP01S first experience – owenduffy.net
-
On negative VSWR – Return Loss implications – owenduffy.net
-
On negative VSWR – a worked example – owenduffy.net
-
owenduffy.net – Page 108 – Mostly electronics…
-
On negative VSWR – owenduffy.net
-
Trying to make sense of the STC U8W chip programmer – owenduffy.net
-
Fox flasher MkII – update 07/2019 – owenduffy.net
-
The private and public scope of coaxial cable – owenduffy.net
-
Average power of SSB telephony – experimental verification – owenduffy.net
-
Power rating of a ferrite cored transformer or balun – owenduffy.net
-
Average power of SSB telephony – owenduffy.net
-
Fox flasher MkII – high power 2 LED solar powered beacon – update 6/2019 – owenduffy.net
-
owenduffy.net – Page 107 – Mostly electronics…
-
Fox flasher MkII – high power 2 LED solar powered beacon – update 6/2018 – owenduffy.net
-
High end VSWR compensation in a ferrite cored RF transformer – owenduffy.net
-
Estimating the Insertion VSWR in a ferrite cored RF transformer – owenduffy.net
-
Estimating the magnetising or core loss in a ferrite cored RF transformer – owenduffy.net
-
Derating rectifier diode current – owenduffy.net
-
Using SPICE on antenna baluns – owenduffy.net
-
Guanella’s 1:1 balun and his explanation – Zcm – owenduffy.net
-
Hitachi DB3DL2 UC3SFL repair – owenduffy.net
-
Guanella’s 1:1 balun and his explanation – owenduffy.net
-
Exploiting your antenna analyser #30 – owenduffy.net
-
EFHW exploration – Part 2: practical examples of EFHW – owenduffy.net
-
owenduffy.net – Page 106 – Mostly electronics…
-
EFHW exploration – Part 1: basic EFHW – owenduffy.net
-
Pawsey Balun – what is it good for? – owenduffy.net
-
Pawsey Balun on an asymmetric load – bench load simulation – owenduffy.net
-
Pawsey Balun on an asymmetric load – owenduffy.net
-
Feasibility study – loop in ground for rx only on low HF – small broadband RF transformer using medium µ ferrite core for receiving use – 50:200Ω – owenduffy.net
-
Nagoya NA-771 2m/70cm antenna – owenduffy.net
-
Capacity test of aftermarket NB-6L batteries #2 – owenduffy.net
-
A balun puzzle – discussion – owenduffy.net
-
A balun puzzle – owenduffy.net
-
Capacity test of aftermarket NB-6L batteries – owenduffy.net
-
owenduffy.net – Page 105 – Mostly electronics…
-
Equivalent noise bandwidth – IC-7300 CW Rx Filter2 – (500Hz sharp) – owenduffy.net
-
Equivalent noise bandwidth – IC-7300 SSB Rx Filter2 – (2400Hz sharp) – owenduffy.net
-
DSZH WK-6889 – temperature sensor – owenduffy.net
-
Post implementation review R134a replaced with HyChill Minus 30 – owenduffy.net
-
Geometry factors for some common Fair-rite binocular ferrite cores – owenduffy.net
-
A symmetric compensation stub using coax – owenduffy.net
-
Measuring trap resonant frequency with an antenna analyser – measurement of a real trap – owenduffy.net
-
Measuring trap resonant frequency with an antenna analyser – owenduffy.net
-
owenduffy.net – Page 104 – Mostly electronics…
-
Comparison of R134a and HyChill Minus 30 – owenduffy.net
-
Exploring HyChill Minus 30 – owenduffy.net
-
Inherently balanced ATUs – part 4 – owenduffy.net
-
Broadband providers are not equal – owenduffy.net
-
Inherently balanced ATUs – part 3 – owenduffy.net
-
Inherently balanced ATUs – part 2 – owenduffy.net
-
Inherently balanced ATUs – owenduffy.net
-
Voltage symmetry of practical Ruthroff 4:1 baluns – finding TLT Vout/Vin – owenduffy.net
-
A low Insertion VSWR high Zcm Guanella 1:1 balun for HF – more detail #3 – owenduffy.net
-
A low Insertion VSWR high Zcm Guanella 1:1 balun for HF – more detail #2 – owenduffy.net
-
De-embedding transmission line to allow remote measurement – owenduffy.net
-
Another measurement of a balunâs Insertion VSWR – owenduffy.net
-
An interesting case study of measurement of a balun’s Insertion VSWR – owenduffy.net
-
owenduffy.net – Page 103 – Mostly electronics…
-
Review – Chinese heating / cooling controller ITC-308 – owenduffy.net
-
Choosing a toroidal magnetic core – ID and OD – owenduffy.net
-
W0SJ matching transformer for an EFLW (Laird 28B1540-000) – owenduffy.net
-
Sumo broadband Internet access – owenduffy.net
-
Exetel broadband Internet access – owenduffy.net
-
Online expert on coax loss – owenduffy.net
-
Voltage symmetry of practical Ruthroff 1:1 baluns – owenduffy.net
-
Voltage symmetry of practical Ruthroff 4:1 baluns – owenduffy.net
-
owenduffy.net – Page 102 – Mostly electronics…
-
AIM 916 produces internally inconsistent results – owenduffy.net
-
VU3SQM directional wattmeter build – #4 – owenduffy.net
-
W5KV’s transmitting loop measurements – DELUXE HG-1 PreciseLOOP 7MHz – owenduffy.net
-
Measuring common mode current with a scope – owenduffy.net
-
Australian amateur population trends 1998 – 2018 – owenduffy.net
-
VU3SQM directional wattmeter build – #3 – owenduffy.net
-
owenduffy.net – Page 101 – Mostly electronics…
-
Designing a Gamma Match – confirmation of as-built antennas – owenduffy.net
-
Measuring balun common mode impedance – #1 – owenduffy.net
-
VU3SQM directional wattmeter build – #2 – owenduffy.net
-
KA0KA’s Youtube test of ATU balance – owenduffy.net
-
VU3SQM directional wattmeter build – #1 – owenduffy.net
-
Elecraft CP-1 directional coupler – magnetics review – owenduffy.net
-
The first 21 days of Exetel broadband Internet access – owenduffy.net
-
On Thevenin’s theorem – #2 – owenduffy.net
-
On Thevenin’s theorem – owenduffy.net
-
owenduffy.net – Page 100 – Mostly electronics…
-
Counterfeit FTDI – another form – owenduffy.net
-
The first seven days of Exetel broadband Internet access – owenduffy.net
-
ISP adapter for Arduino Pro Mini / Pro Micro – owenduffy.net
-
Yet another change of Internet broadband access – owenduffy.net
-
IoT – exploration of LoRa – part 2 – owenduffy.net
-
A low Insertion VSWR high Zcm Guanella 1:1 balun for HF – owenduffy.net
-
IoT – exploration of LoRa – part 1 – owenduffy.net
-
RFPM2 – calibration files – owenduffy.net
-
RFPM2 – calibration – owenduffy.net
-
RF Power Meter 2 (RFPM2) – owenduffy.net
-
owenduffy.net – Page 99 – Mostly electronics…
-
Arduino SAMD21 bootloader protection II – owenduffy.net
-
Motorola TAD1000B Folded Coaxial Antenna – discussion – owenduffy.net
-
An explanation of W5DXP’s ‘line extender device’ – owenduffy.net
-
Rigexpert’s Antscope takes a bigger step backwards – owenduffy.net
-
owenduffy.net – Page 98 – Mostly electronics…
-
AIM 915a produces internally inconsistent results – owenduffy.net
-
Dragino LG02 review – owenduffy.net
-
ESP8266 IoT BME280 temperature, humidity and pressure – owenduffy.net
-
IoT – exploration of LoRaWAN – part 1 – owenduffy.net
-
AIM 915 produces internally inconsistent results – owenduffy.net
-
When simple explanations target a simple audience – owenduffy.net
-
Hams helping hams – owenduffy.net
-
Australian amateur radio licensing reform (2018) – owenduffy.net
-
Measuring ambient noise level using a spectrum analyser #2 – owenduffy.net
-
owenduffy.net – Page 97 – Mostly electronics…
-
Online calculator of ferrite material permeability interpolations – additional materials – owenduffy.net
-
Balancing a ceiling fan – owenduffy.net
-
Amateur Radio – Page 68 – owenduffy.net
-
Antenna Tuners (ATU) – Page 5 – owenduffy.net
-
Radio-Kits SWR meter – build and review – owenduffy.net
-
Antennas – Page 40 – owenduffy.net
-
Backtracking in APRS – owenduffy.net
-
Mapping trips from APRS archives – owenduffy.net
-
Zig zags in APRS tracks – owenduffy.net
-
APRS – Page 2 – owenduffy.net
-
APRS – Page 8 – owenduffy.net
-
?feed=rss2&cat=6
-
Inside the YHDC SCT013 current transformer – owenduffy.net
-
SCT-010-000 current transformer protection – owenduffy.net
-
EmonTx3 v3.4 ‘wired’ implementation – owenduffy.net
-
Arduino 1.6.12 – adding Optiboard boards.txt – owenduffy.net
-
Arduino 1.6.12 & 1.6.13 AVRDUDE issues – owenduffy.net
-
ADS1115 ADC checkout – #1 – owenduffy.net
-
Fan controlled by humidity sensor – pre implementation data gathering – owenduffy.net
-
Fan controlled by humidity sensor – owenduffy.net
-
Time to get some experience with 32bit microcontrollers – some progress – owenduffy.net
-
Time to get some experience with 32bit microcontrollers – owenduffy.net
-
Arduino thermistor thermometer – a tutorial – owenduffy.net
-
Fan controlled by humidity sensor – design technique – owenduffy.net
-
Arduino app to set DS1307 Real Time Clocks – owenduffy.net
-
Arduino – Page 2 – owenduffy.net
-
Arduino – Page 3 – owenduffy.net
-
?feed=rss2&cat=15
-
Review of the Amidon AB_200_10 balun – owenduffy.net
-
A low Insertion VSWR high Zcm Guanella 1:1 balun for HF – more detail – owenduffy.net
-
Baluns – Page 2 – owenduffy.net
-
Baluns – Page 7 – owenduffy.net
-
?feed=rss2&cat=24
-
ESP8266 IoT DHT22 temperature and humidity – evolution 3 – owenduffy.net
-
NodeMCU devkit V1 deep sleep – owenduffy.net
-
ESP8266 remote power display for energy monitor – EV3 – 5V display – owenduffy.net
-
ESP8266 remote power display for energy monitor – EV3 – owenduffy.net
-
ESP8266 remote power display for energy monitor – owenduffy.net
-
ESP8266 remote power display for energy monitor – EV2 – owenduffy.net
-
ESP8266 IoT DHT22 temperature and humidity – evolution 2 – owenduffy.net
-
Computing – Page 2 – owenduffy.net
-
Computing – Page 6 – owenduffy.net
-
?feed=rss2&cat=26
-
Apples have just come off the trees – owenduffy.net
-
?feed=rss2&cat=23
-
WBT-4000W 230V AC dimmer / motor speed controller – owenduffy.net
-
A flexible test panel for microcontroller based power control projects – #2 – owenduffy.net
-
A flexible test panel for microcontroller based power control projects – owenduffy.net
-
Electrical – Page 2 – owenduffy.net
-
Electrical – Page 4 – owenduffy.net
-
?feed=rss2&cat=10
-
Electronics – Page 2 – owenduffy.net
-
Electronics – Page 21 – owenduffy.net
-
?feed=rss2&cat=7
-
Maker – Page 2 – owenduffy.net
-
Maker – Page 13 – owenduffy.net
-
?feed=rss2&cat=34
-
Measurement – Page 2 – owenduffy.net
-
Measurement – Page 6 – owenduffy.net
-
?feed=rss2&cat=28
-
Cheap Chinese wristwatch #2 – owenduffy.net
-
Cheap Chinese wristwatch #1 – owenduffy.net
-
Mandarin & Lime Marmalade – owenduffy.net
-
Australian Lime & Lemon Marmalade – owenduffy.net
-
Tahitian Lime Marmalade – owenduffy.net
-
Australian Lime Marmalade – owenduffy.net
-
The old wheelbarrow will not die – owenduffy.net
-
Leafeater retro fit – owenduffy.net
-
?feed=rss2&cat=5
-
A little programming adapter for 4 x 2mm pitch pads – owenduffy.net
-
Inductance of sensorless brushless DC motors – owenduffy.net
-
A Demagnetisation Risk Index for a sensorless brushless DC drive – owenduffy.net
-
Standardised processing of instrument screen captures – owenduffy.net
-
Demagnetisation in a sensorless brushless DC drive – owenduffy.net
-
Hobbyking Multistar 4220-650Kv – owenduffy.net
-
Regenerative braking and electronic power supplies – owenduffy.net
-
RCTimer 4215-530Kv BLDC motor checkout – owenduffy.net
-
CC3D F4 fraud – owenduffy.net
-
RC models – Page 2 – owenduffy.net
-
RC models – Page 7 – owenduffy.net
-
?feed=rss2&cat=12
-
Anytone AT-D868UV: initial impressions – owenduffy.net
-
Calibrating the Elecraft N-GEN – owenduffy.net
-
Calculation of received noise power given ENB and ENR – owenduffy.net
-
Equivalent noise bandwidth – IC-7300 SSB Rx Filter2 (2400Hz soft) – owenduffy.net
-
IC-7300 S-meter calibration accuracy – owenduffy.net
-
Receivers – Page 2 – owenduffy.net
-
Receivers – Page 5 – owenduffy.net
-
?feed=rss2&cat=30
-
A cheap and cheerful data logger – owenduffy.net
-
Raspberry Pi 2 initial impressions – owenduffy.net
-
On-air testing of APRS digipeater with a crafted suite of test records – owenduffy.net
-
RPi headless aprx server using soundmodem – owenduffy.net
-
Cron configuration improvements for Raspberry Pi – owenduffy.net
-
Real time clock for Raspberry Pi – owenduffy.net
-
Notes on my fork of aprx – owenduffy.net
-
Headless aprx APRS server – RPi packages – owenduffy.net
-
Headless aprx server trial – owenduffy.net
-
Headless aprx server – trial wrapup – owenduffy.net
-
Towards a reliable APRS iGate – #2 – owenduffy.net
-
Towards a reliable APRS iGate – owenduffy.net
-
RPi – Page 2 – owenduffy.net
-
?feed=rss2&cat=29
-
Slot.it orange CA20Z build – owenduffy.net
-
Slot.it CS23B build – owenduffy.net
-
Slot.it CA20Z build – owenduffy.net
-
Slot.it CA20A rework – owenduffy.net
-
?feed=rss2&cat=31
-
AE7PD’s transmitting loop measurements – owenduffy.net
-
Findling & Siwiak 2012 measurements of an Alexloop – discussion – owenduffy.net
-
Findling & Siwiak 2012 measurements of an Alexloop – owenduffy.net
-
G3CWI 2018 measurements of an Alexloop Walkham – owenduffy.net
-
Single turn coaxial loop resonator analysis – owenduffy.net
-
G3CWI’s ground wave tests Jul 2017 using WSPRlite – owenduffy.net
-
STL propaganda indeed: QW vertical – dipole – STL model pattern comparison – owenduffy.net
-
STL propaganda indeed: dipole – STL pattern comparison – owenduffy.net
-
STL propaganda indeed – owenduffy.net
-
Small Transmitting Loops – Page 2 – owenduffy.net
-
Small Transmitting Loops – Page 9 – owenduffy.net
-
?feed=rss2&cat=4
-
First full month of Amaysim broadband broadband Internet access – owenduffy.net
-
First full week of Amaysim broadband Internet access – owenduffy.net
-
Review of 10 months of iiNet broadband Internet access – owenduffy.net
-
iiNet broadband Internet access – speed observations – owenduffy.net
-
Review of 5 months of iiNet broadband Internet access – owenduffy.net
-
First month of iiNet FTTN broadband Internet access – owenduffy.net
-
Queueing in data networks – owenduffy.net
-
Telecommunications – Page 2 – owenduffy.net
-
?feed=rss2&cat=2
-
WW1WW’s matching transformer for an EFHW – owenduffy.net
-
PD7MAA’s BN43-202 matching transformer for an EFHW – owenduffy.net
-
AIM 914 produces internally inconsistent results – owenduffy.net
-
Test equipment – Page 2 – owenduffy.net
-
Test equipment – Page 17 – owenduffy.net
-
?feed=rss2&cat=11
-
Transmission lines – Page 2 – owenduffy.net
-
Transmission lines – Page 26 – owenduffy.net
-
?feed=rss2&cat=13
-
VSWR meter trap for the unwary – owenduffy.net
-
40m filter for WSPRlite flex – owenduffy.net
-
Another RFI mod of a speaker mic for DMR use – owenduffy.net
-
Transmitters – Page 2 – owenduffy.net
-
Transmitters – Page 16 – owenduffy.net
-
?feed=rss2&cat=1
-
RBN for antenna comparisons – Radcom 2018 – owenduffy.net
-
A tutorial on estimating the impedance of a toroidal ferrite cored inductor for radio frequencies – owenduffy.net
-
W3LPL’s paired WSPRlite test – test 2 – owenduffy.net
-
Signed application programs – owenduffy.net
-
AIM 865A Refer to Antenna facility – owenduffy.net
-
Measuring balun common mode impedance – #2 – owenduffy.net
-
AIM 865A produces inconsistent / incorrect results – owenduffy.net
-
AIM 882 produces internally inconsistent results – owenduffy.net
-
Uncategorized – Page 2 – owenduffy.net
-
ic9350 updated to support 3040 – owenduffy.net
-
Roger Beep fitted to MFJ-1263 microphone / rig switch – owenduffy.net
-
Tunemate update – owenduffy.net
-
VK1OD Roger Beep project documentation – owenduffy.net
-
?feed=rss2&tag=aim-use-issues
-
Accuracy of AIMuhf system – AIM910B vs several recent versions on a ferrite cored inductor – owenduffy.net
-
Accuracy of AIMuhf system – AIM910A vs several recent versions on a ferrite cored inductor – owenduffy.net
-
Characterising an unknown ferrite toroid – owenduffy.net
-
2.4:1 balun design failure – owenduffy.net
-
A walk through of a practical application of AIMuhf/AIM900A #2 – owenduffy.net
-
A walk through of a practical application of AIMuhf/AIM900 – owenduffy.net
-
AIM use & issues – Page 2 – owenduffy.net
-
AIM use & issues – Page 3 – owenduffy.net
-
?feed=rss2&tag=designing-high-performance-vhfuhf-receive-systems
-
Designing high performance VHF/UHF receive systems – Part 7 – owenduffy.net
-
Designing high performance VHF/UHF receive systems – Part 6 – owenduffy.net
-
Designing high performance VHF/UHF receive systems – Part 5 – owenduffy.net
-
Designing high performance VHF/UHF receive systems – Part 4 – owenduffy.net
-
Designing high performance VHF/UHF receive systems – Part 3 – owenduffy.net
-
Designing high performance VHF/UHF receive systems – Part 2 – owenduffy.net
-
Designing high performance VHF/UHF receive systems – Part 1 – owenduffy.net
-
?feed=rss2&tag=exploiting-your-antenna-analyser
-
Exploiting your antenna analyser #29 – owenduffy.net
-
Exploiting your antenna analyser #28 – owenduffy.net
-
Exploiting your antenna analyser #27 – owenduffy.net
-
Exploiting your antenna analyser #26 – owenduffy.net
-
Exploiting your antenna analyser – contents – owenduffy.net
-
Exploiting your antenna analyser #25 – owenduffy.net
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Exploiting your antenna analyser #24 – owenduffy.net
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Exploiting your antenna analyser #23 – owenduffy.net
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Exploiting your antenna analyser #22 – owenduffy.net
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Exploiting your antenna analyser #21 – owenduffy.net
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Exploiting your antenna analyser – Page 2 – owenduffy.net
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Exploiting your antenna analyser – Page 3 – owenduffy.net
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?feed=rss2&tag=ic-7410-tests
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IC-7410 tests – 03 – Noise Figure – owenduffy.net
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IC-7410 tests – 02 – digital audio output – owenduffy.net
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IC-7410 tests – 01 – linearity – owenduffy.net
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?feed=rss2&tag=noise-figure-meter
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Using an attenuator for NoiseLo/NoiseHi in NFM – owenduffy.net
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VK2OMD ambient noise measurement 144MHz – 20140217 – owenduffy.net
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?feed=rss2&tag=rfpm1
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Return Loss sweep using IC7410, RL bridge, and RFPM1 – owenduffy.net
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A prototype data logger for RFPM1 – owenduffy.net
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Transmit performance of 2m hand held transceivers – absolute gain estimates – owenduffy.net
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Transmit performance of 2m hand held transceivers – owenduffy.net
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Near-field field strength measurements using the RFPM1 – owenduffy.net
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Review of Boswell et al paper “Performance of a small loop antenna in the 3-10 MHz band” – owenduffy.net
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VK3AQZ RF power meter (RFPM1) – adjust Tx power example – owenduffy.net
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VK3AQZ RF power meter (RFPM1) – filter response example – owenduffy.net
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dB, dBi, and dBd – owenduffy.net
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On Witt’s calculation of Matched Line Loss from Return Loss – owenduffy.net
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Review of inexpensive Chinese thermostat – 8010F #2 – owenduffy.net
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Programming jig for STC15Fx DIP-8, DIP-28 chips – owenduffy.net
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Flashing LED driver using an ESC – owenduffy.net
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Review of inexpensive Chinese thermostat – MH-1210 #2 – owenduffy.net
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Using the AIM to measure matched line loss – owenduffy.net
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Thermistor for CBAIV – owenduffy.net
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Baofeng GT-3TP MkIII review – owenduffy.net
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Antenna span tensioner using a counterweighted halyard – owenduffy.net
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Antenna span spring tensioner – owenduffy.net
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June 2015 – Page 2 – owenduffy.net
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June 2015 – Page 3 – owenduffy.net
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Dodgy Chinese thermocouple thermometer – owenduffy.net
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A test run of the generic heating / cooling controller with 10k NTC thermistor sensor – owenduffy.net
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Thermal observations on Neosid 28-053-31 ferrite toroid – owenduffy.net
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Interpreting temperature rise in ferrite cored RF transformers and inductors – owenduffy.net
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owenduffy.net – Page 3 – Mostly electronics…
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December 2018 – Page 2 – owenduffy.net
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November 2018 – Page 2 – owenduffy.net
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Matched Line Loss of generic RG6/U Quad Shield CCS – owenduffy.net
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KN5L measurement of JSC 1318 windowed ladder line – MLL @ 4.2MHz – owenduffy.net
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Transmission line measurements – learning from failure – owenduffy.net
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Inferring Matched Line Loss from Half Return Loss measurements – Zo error – owenduffy.net
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Feasibility study – loop in ground for rx only on low HF – small broadband RF transformer – discussion of ferrite material choice – owenduffy.net
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Feasibility study – loop in ground for rx only on low HF – SDR for measurement? – owenduffy.net
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August 2018 – Page 2 – owenduffy.net
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Implementation of G5RV inverted V using high strength aluminium MIG wire – 12 month review – owenduffy.net
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Pulsar V233-0060 stripped down – owenduffy.net
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WSPR for A/B tests – a discussion – part 4 – owenduffy.net
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WSPR for A/B tests – a discussion – part 3 – owenduffy.net
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Initial review of Owon virtual (USB) oscilloscopes – owenduffy.net
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WSPR for A/B tests – a discussion – part 2 – owenduffy.net
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Adjusting modulation level on FM mobiles etc. – owenduffy.net
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Agat Russian mechanical stopwatch fix – owenduffy.net
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WSPR for A/B tests – a discussion – part 1 – owenduffy.net
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March 2018 – Page 2 – owenduffy.net
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January 2018 – Page 2 – owenduffy.net
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Chinese no-name 1-500MHz Return Loss Bridge – owenduffy.net
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Comparing toroidal inductors of different core dimensions – owenduffy.net
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Molasses derusting of steel – owenduffy.net
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Review of inexpensive Chinese thermostat – MH1230A – owenduffy.net
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On winding configuration of EFHW matching transformers – owenduffy.net
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The sign of reactance – challenge reality check – owenduffy.net
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The sign of reactance – a challenge – owenduffy.net
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The sign of reactance – challenge solution – owenduffy.net
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The sign of reactance – challenge discussion – owenduffy.net
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Ellington 3 x FT240-52 matching transformer for an EFHW – owenduffy.net
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Tuned Plate Tuned Grid oscillator – a simple, but complete explanation – owenduffy.net
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What is a Ground Plane Antenna? – owenduffy.net
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G3LNP balun with symmetric ‘matched’ load – owenduffy.net
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G3LNP balun – owenduffy.net
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Fixes #1: magnetic stirrer with heating plate and digital display XB 85-2 – owenduffy.net
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Review: magnetic stirrer with heating plate and digital display XB 85-2 – owenduffy.net
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October 2017 – Page 2 – owenduffy.net
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A low cost 50Ω termination for measurement purposes – owenduffy.net
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DL4YHF 50MHz counter on a Chinese TB-244746 PCB – owenduffy.net
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“No short antenna is more efficient than a resonant-length antenna” – owenduffy.net
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Small untuned loop with MMIC LNA on 80m – owenduffy.net
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Failure to treat impedance as a complex quantity leads to… – owenduffy.net
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Demonstration of the GR1606B for antenna Z measurement and calcs – owenduffy.net
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4-20mA Pt100 input for the generic heating / cooling controller – owenduffy.net
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September 2017 – Page 2 – owenduffy.net
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GPS antenna plot – owenduffy.net
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August 2017 – Page 2 – owenduffy.net
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Chinese batteries – 5 x 2/3A 1.6Ah NiMH cells – owenduffy.net
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Chinese BN-V11U NiMH replacement battery – owenduffy.net
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Review of Hantek DSO8102E hand held oscilloscope – owenduffy.net
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July 2017 – Page 2 – owenduffy.net
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Extrapolating VSWR of a simple series resonant antenna – owenduffy.net
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Typical zinc thickness on zinc coated products used for antennas – owenduffy.net
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80m half wave dipole made from galvanised fence wire – owenduffy.net
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Finding the inductance of the outside of LDF4-50A – owenduffy.net
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Loss components in an NEC model of a Small Transmitting Loop – owenduffy.net
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Measuring SSB telephony Peak Envelope Power – owenduffy.net
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Exploiting waveguide mode of the loop conductor in a small transmitting loop – owenduffy.net
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June 2017 – Page 2 – owenduffy.net
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A search for some mid power white wide angle LEDs – owenduffy.net
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Shunt matching a loaded HF whip – discussion – owenduffy.net
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Shunt matching a loaded HF whip with just a VSWR meter – owenduffy.net
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Power in a mismatched transmission line – owenduffy.net
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G4JNT’s observation of bandwidth effects on WSPR SNR – owenduffy.net
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Small untuned loop for receiving – NEC model – owenduffy.net
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W3LPL’s paired WSPRlite test – test 1 – owenduffy.net
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May 2017 – Page 2 – owenduffy.net
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The Mobius strip loop – ham benefits – owenduffy.net
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The fraud of energy efficient lighting – LED lighting – owenduffy.net
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Quiet HF antennas and E and H fields in the near field zone – owenduffy.net
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LNR Precision small transmitting loop – owenduffy.net
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Current and voltage implications of a small transmitting loop power ratings – owenduffy.net
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CHA P-Loop 2.0 small transmitting loop – owenduffy.net
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April 2017 – Page 2 – owenduffy.net
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Review of Dodd’s WSPR based antenna comparison – owenduffy.net
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Loss in open wire + coax hybrid feed arrangements – owenduffy.net
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Loss of windowed ladder line at MF/HF/VHF – owenduffy.net
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March 2017 – Page 2 – owenduffy.net
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Modifications for Jasic 200A TIG welder and pedal – owenduffy.net
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NH7RO 7-foot diameter QRO STL for 40M – owenduffy.net
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Check / calibrate frequency accuracy of IC-7300 – owenduffy.net
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Does common mode current flow inside coax? – owenduffy.net
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PD7MAA’s BN43-202 matching transformer for an EFHW – full measurement set – owenduffy.net
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Thoughts on binocular ferrite core inductors at radio frequencies – owenduffy.net
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Common failings of EFHW matching transformers – owenduffy.net
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PD7MAA’s BN43-202 matching transformer for an EFHW – measurement of a prototype – owenduffy.net
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Earth electrodes in parallel – owenduffy.net
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January 2017 – Page 2 – owenduffy.net
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Tytera MD-390 DMR portable evaluation – owenduffy.net
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Improving quadcopter stability at very low throttle using Complementary PWM – owenduffy.net
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Max thrust: Hobbywing XRotor 40A (MkII) vs BLHeli Hobbywing XRotor 40A (MkII) vs SimonK Hobbyking 9261000003 40A – owenduffy.net
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AU ordinary power plug, plug packs and extension cord sockets – owenduffy.net
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BLHeli Hobbywing XRotor 40A (MkII) vs SimonK Hobbyking 9261000003 40A – owenduffy.net
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BLHeli 14.8 damped light and active freewheeling – owenduffy.net
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Hobbywing XRotor 40A (MkII) – owenduffy.net
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December 2016 – Page 2 – owenduffy.net
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Grebenkember’s original Tandem match – owenduffy.net
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KitsAndParts.com QRP SWR bridge – owenduffy.net
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DMR distance limit – owenduffy.net
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TV upgrade – MER optimisation – owenduffy.net
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TV upgrade – owenduffy.net
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Coil32 inductance calculator – owenduffy.net
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Some thinking on ground wave as we enter another solar minimum – owenduffy.net
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Polarisation of man made noise – an 80m case – owenduffy.net
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Polarisation of man made noise – owenduffy.net
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Backup for NBN VDSL access – owenduffy.net
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Small signal diode characteristics – owenduffy.net
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Android and local IPv4 DNS name resolution – owenduffy.net
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October 2016 – Page 2 – owenduffy.net
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October 2016 – Page 3 – owenduffy.net
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Cheap Chinese compression connector tool – owenduffy.net
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Zo of two wire line – owenduffy.net
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The sign of Return Loss – owenduffy.net
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Is the premises main earthing conductor ok as a lightning down conductor – owenduffy.net
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Rationale for sizing of lightning down conductor – owenduffy.net
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Rigexpert Antscope v4.2.83 released – owenduffy.net
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September 2016 – Page 2 – owenduffy.net
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September 2016 – Page 3 – owenduffy.net
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Tuning combiner lines – owenduffy.net
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Treatment of the -ve DC return path for transceivers in mobile installations – owenduffy.net
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Antenna analysers – the basics – QST Aug 2016 – owenduffy.net
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August 2016 – Page 2 – owenduffy.net
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Another chapter in the NBN debacle – Jul 2016 – owenduffy.net
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InsertionVSWR of Red Dot 2016A – owenduffy.net
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InsertionVSWR of Grebenkemper’s Tandem Match – owenduffy.net
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InsertionVSWR of Revex W560 on HF – owenduffy.net
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KG-UV920P repair / modification for driver FET failure – owenduffy.net
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July 2016 – Page 2 – owenduffy.net
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July 2016 – Page 3 – owenduffy.net
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Atten APS3005S – a better thermostatic fan control – owenduffy.net
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Silver vs alkaline button cells – owenduffy.net
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Micro SD card premature failure – owenduffy.net
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Chinese counterfeiters at it again – EZP2013 – owenduffy.net
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Some automation to supplement Cleanflight-configurator – owenduffy.net
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June 2016 – Page 2 – owenduffy.net
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On copper loss in transmitting baluns – owenduffy.net
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MultiStar 5200mAh 3S Lipo – initial tests – owenduffy.net
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Exploiting your antenna analyser #20 – owenduffy.net
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Exploiting your antenna analyser #8 – owenduffy.net
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Analysis of a certain dipole animation – OCF implications – owenduffy.net
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Analysis of a certain dipole animation – owenduffy.net
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Exploiting your antenna analyser #19 – owenduffy.net
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Voltage withstand of Vero strip board – owenduffy.net
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May 2016 – Page 2 – owenduffy.net
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On use of enameled wire in transmitting baluns – owenduffy.net
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Exploiting your antenna analyser #15 – owenduffy.net
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Assessing the Q of a half wave dipole antenna system – a real world example – owenduffy.net
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Assessing the Q of a half wave dipole antenna system – owenduffy.net
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Field strength survey of an M40-1 short helical vertical on 40m – owenduffy.net
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USB-A to DC 5.5/2.1mm power cable – current carrying capacity – owenduffy.net
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PIK – owenduffy.net
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Counterfeit FTDI – owenduffy.net
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Exploiting your antenna analyser #10 – owenduffy.net
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Exploiting your antenna analyser #9 – owenduffy.net
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Graphic demonstration of loss under standing waves #2 – owenduffy.net
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December 2015 – Page 2 – owenduffy.net
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December 2015 – Page 3 – owenduffy.net
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Belrose field strength measurements of his 80m mobile whip – owenduffy.net
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On ignoring capacitor losses in Small Transmitting Loops – owenduffy.net
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NEC study of Small Transmitting Loop Q vs frequency – owenduffy.net
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K4PP’s 1m Small Transmitting Loop – owenduffy.net
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November 2015 – Page 2 – owenduffy.net
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OpenLog for TinyTrak – drive test – owenduffy.net
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Steel wire CF dipole on 160m – owenduffy.net
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October 2015 – Page 2 – owenduffy.net
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Differential flux leakage in a Guanella 1:1 balun – owenduffy.net
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DYS SN20A out of the box – owenduffy.net
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Review of G3LDO STL (Radcom Sep 2010) – owenduffy.net
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September 2015 – Page 2 – owenduffy.net
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APRS trial Bowral – Wilton – Wollongong – Macquarie Pass – Bowral – owenduffy.net
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August 2015 – Page 2 – owenduffy.net
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Solar power supply for foxflasher2 – owenduffy.net
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Arduino HMC5883 magnetometer – a tutorial – owenduffy.net
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Arduino stepper motor – a tutorial – owenduffy.net
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An interesting case study – in service evaluation of coax loss – owenduffy.net
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July 2015 – Page 2 – owenduffy.net
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Amateur Radio – Page 67 – owenduffy.net
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APRS – Page 3 – owenduffy.net
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APRS – Page 7 – owenduffy.net
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BG7TBL noise source – owenduffy.net
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Baluns – Page 3 – owenduffy.net
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Baluns – Page 6 – owenduffy.net
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Inductance of a loop of CAT5 pair – owenduffy.net
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Computing – Page 3 – owenduffy.net
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Computing – Page 5 – owenduffy.net
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Electrical – Page 3 – owenduffy.net
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Electronics – Page 3 – owenduffy.net
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Maker – Page 3 – owenduffy.net
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Maker – Page 12 – owenduffy.net
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?s=RFPM2&feed=rss2
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?s=RFPM1&feed=rss2
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?s=rfpm1&feed=rss2
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Measurement – Page 3 – owenduffy.net
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Measurement – Page 5 – owenduffy.net
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RC models – Page 3 – owenduffy.net
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RC models – Page 6 – owenduffy.net
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Receivers – Page 3 – owenduffy.net
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A check load for antenna analysers with UHF series socket – owenduffy.net
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Small Transmitting Loops – Page 3 – owenduffy.net
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Small Transmitting Loops – Page 8 – owenduffy.net
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Online calculator of ferrite material permeability interpolations – owenduffy.net
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Another small broadband RF transformer using medium µ ferrite core for receiving use – 50:450Ω – owenduffy.net
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Another small broadband RF transformer using medium µ ferrite core for receiving use – 50:3200Ω – owenduffy.net
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Test equipment – Page 3 – owenduffy.net
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Test equipment – Page 16 – owenduffy.net