The Loop in Ground project is about a receive only antenna for low HF, but usable from MF to HF. The objective is an antenna of that is small, low profile, and can be located outside the zone where evanescent modes dominate around noise current carrying conductors, like house wiring to minimise noise pickup. To … Continue reading Loop in ground (LiG) for rx only on low HF – #10 SND comparison with LoG
Feasibility study – loop in ground for rx only on low HF – signal / noise degradation (SND) gave the following graph. This article explains a little of the detail behind the graph. Last update: 2nd January, 2022, 5:59 AM
Feasibility study – loop in ground for rx only on low HF laid out an initial design concept. This article sets out expected signal / noise degradation in a typical installation. 3.5MHz Let’s take ambient noise as Rural precinct in ITU-P.372-14. An NEC-5.0 model of the 3m a side LiG gives average gain -37.18dBi. An … Continue reading Loop in ground (LiG) – #6 signal to noise degradation (SND)
The nature of radio signals received off-air is that they are accompanied by undesired noise. A key measure of the ability to decode a radio signal is its Signal to Noise ratio (S/N) at the demodulator (or referred to some common point). We can speak of think of an external S/N figure as in dB. … Continue reading Signal to noise degradation (SND) concept
Three recent articles developed an explanation of the YouLoop-2T at MF/lowHF: Small untuned loop for receiving – simple model with transformer ; A transmission line 1:4 impedance transformer ; and Towards understanding the YouLoop-2T at MF/lowHF . The first and third articles explained the concept of signal/noise degradation (SND) statistic, and gave graphs of the … Continue reading SND implications of variations on the untuned small loop at MF/lowHF
A recent posting on social media kicked off some discussion about infinite gain preamplifiers, mostly in the context of an unloaded very short vertical. Over the past couple of years I’ve had a number of comments and questions about active antennas, instigated by my ARRL book, Receiving Antennas for the Radio Amateur. The “main ingredient” … Continue reading The need for infinite preamplifier gain?
The article The oft asked question of how much an LNA improves a 70cm weak signal station solicited some comment on optimal configurations. This article deals with the notion / Rule of Thumb that optimal LNA gain is just sufficient to offset line losses. This article explains with graphs the relationship between Signal / Noise degradation … Continue reading The oft asked question of how much an LNA improves a 70cm weak signal station – Rules of Thumb
A recent online post seeking opinions on the chap’s 70cm weak signal configuration is an interesting subject for study, and one that should be of interest to many weak signal DXers. This article focusses on just one question in a quite similar configuration, what is the advantage given by the LNA? Study configuration The scenario … Continue reading The oft asked question of how much an LNA improves a 70cm weak signal station
This article was revised 03/01/2021 to correct an error: the NEC-5.0 model reported was actually the KK5JY LoG, fixed, apologies. The Loop in Ground project is about a receive only antenna for low HF, but usable from MF to HF. The objective is an antenna of that is small, low profile, and can be located … Continue reading Loop in ground (LiG) for rx only on low HF – #8 measurement and observation
The Loop in Ground project is about a receive only antenna for low HF, but usable from MF to HF. The objective is an antenna that has low Signal to Noise Degradation (SND), and low noise pickup by virtue of some separation of near field radiators. The antenna comprises a square loop of 3m sides … Continue reading Loop in ground (LiG) – #10 – implementation – earthworks