The LG LCD television failed after less than 10 years, the LCD backlight would not always start and it became a bigger problem each winter.
Wire current rating for single FEP (Teflon) or Silicone insulated (200°) conductor in free air (30°).
| AWG | Cond dia (mm) | CSA (mm^2) | R/km (Ω) | Imax |
|---|---|---|---|---|
| 2 | 6.5 | 33.6 | 0.513 | 241 |
| 3 | 5.8 | 26.7 | 0.647 | 209 |
| 4 | 5.2 | 21.2 | 0.815 | 180 |
| 5 | 4.6 | 16.8 | 1.03 | 156 |
| 6 | 4.1 | 13.3 | 1.30 | 135 |
| 7 | 3.7 | 10.5 | 1.63 | 117 |
| 8 | 3.3 | 8.37 | 2.06 | 101 |
| 9 | 2.9 | 6.63 | 2.60 | 87.4 |
| 10 | 2.6 | 5.26 | 3.28 | 75.6 |
| 11 | 2.3 | 4.17 | 4.13 | 65.4 |
| 12 | 2.1 | 3.31 | 5.21 | 56.6 |
| 13 | 1.8 | 2.62 | 6.57 | 48.9 |
| 14 | 1.6 | 2.08 | 8.29 | 42.3 |
| 15 | 1.5 | 1.65 | 10.5 | 36.6 |
| 16 | 1.3 | 1.31 | 13.2 | 31.7 |
| 17 | 1.2 | 1.04 | 16.6 | 27.4 |
| 18 | 1.0 | 0.823 | 21.0 | 23.7 |
| 19 | 0.91 | 0.653 | 26.4 | 20.5 |
| 20 | 0.81 | 0.518 | 33.3 | 17.7 |
| 21 | 0.72 | 0.410 | 42.0 | 15.3 |
| 22 | 0.64 | 0.326 | 53.0 | 13.3 |
| 23 | 0.57 | 0.258 | 66.8 | 11.5 |
| 24 | 0.51 | 0.205 | 84.2 | 9.93 |
| 25 | 0.46 | 0.162 | 106 | 8.59 |
| 26 | 0.41 | 0.129 | 134 | 7.43 |
| 27 | 0.36 | 0.102 | 169 | 6.43 |
| 28 | 0.32 | 0.081 | 213 | 5.56 |
| 29 | 0.29 | 0.064 | 269 | 4.81 |
| 30 | 0.26 | 0.051 | 339 | 4.16 |
Derived in part from data published by Wiremax.
Hobbywing Skywalker 40A ESC – initial testing
A set of four Skywalker 40A ESCs were purchased for trial on a tricopter (3 on bird, one spare for testing). They cost about $15 ea incl shipping on eBay, and they appear to be genuine Hobbywing product.
Continue reading Hobbywing Skywalker 40A ESC – initial testing
Speaker cable as RF transmission line
Speaker cable and similar Figure-8 twin in various sizes is popular as RF transmission line, particularly with QRP operators, especially those operating portable in the field (eg SOTA activators). Indeed, SOTA seems to have triggered a revival in the use of these cables. With the large number of online recommendations, one could be forgiven for thinking that a dipole and feed line formed entirely from #24 speaker wire is the antenna of choice.
With that in mind, this article looks at the performance of Jaycar WB1702 speaker cable, 14×0.14mm conductors (#24) with PVC insulation, cost $0.50/m.
Measuring matched line loss
Matched Line Loss (MLL) is the loss or attenuation of a transmission line terminated in its actual characteristic impedance, and usually give for some length, eg dB/100′, dB/100m, dB/m.
One method that occurs in ham radio articles is to measure the input resistance of a resonant s/c or o/c stub, and to calculate MLL as 8.686*Rin/Zo/length dB/unitlength. (This is not the only method, or even a good one, but it is commonly used.)
HK DT750 motor, Afro30 ESC and SimonK 8c2cf42/comp_pwm
Bench tested a DT750 on 3S, Afro30 with 2013-10-29_8c2cf42_comp_pwm, 11×4.5SF and Eagle datalogger. This motor is reported by some to be incompatible with SimonK.
Continue reading HK DT750 motor, Afro30 ESC and SimonK 8c2cf42/comp_pwm
Windowed ladder line loss – G3TXQ
G3TXQ has published (undated) a set of measurements on commercial windowed ladder line at Wet ladderline (accessed 10/01/14).
His measurements are of interest as there is a dearth of credible measurement data for these types of lines below 50MHz. Continue reading Windowed ladder line loss – G3TXQ
Review of Hakko FG-100 soldering iron thermometer
A new Hakko FG-100 arrived from China this week, the meter and pack of 5 sensors cost less than A$12 including post.
Continue reading Review of Hakko FG-100 soldering iron thermometer
Flashing LED driver using an ESC
This article describes a driver for flashing LEDs using a repurposed ESC.
ESC ceramic resonator accuracy
I measured 6 different ESCs (all different types) at 25° with a 16MHz ceramic resonator, and standard deviation was 1200ppm, or 0.12%.