Category: Electronics

Introduction In the previous two posts, I looked at FT8 & WSPR, as part of the WSJT-X protocol suite (Ref.1/2). Using simple antennas like a 5m wire hanging from a tree and an Alex Magnetic loop, I was able to receive signals at extremely low SNR’s. I had only experienced reception under these conditions using… Continue reading HRF1 for WSPR Beacon on GNU Radio

Introduction In the previous post I looked at receiving WSJT-X WSPR using the RTL-SDR (Ref.1). Normally I place my HF antennas outside on my balcony, but due to renovation construction this is not available to me. So I used an Alex Magnetic Loop antenna inside pointing out of the balcony window and even with this… Continue reading RTL-SDR for WSJT-X FT8

Introduction WSPR is part of a suite of communication protocols developed by Dr. Joseph Taylor K1JT, a Nobel Prize winning pulsar researcher (Ref.1). He applied the latest signal processing techniques from his astronomical research to the reception of very weak amateur radio signals. Amateur radio operators can work at signal to noise ratios bordering on… Continue reading RTL-SDR for WSJT-X WSPR

Introduction Six years ago I designed a zero IF direct conversion receiver to be used with my HF Radio Ebook (Ref.1). For flexibility, I used an IQ VFO. At the time, the best choice for my VFO was the Si514. In order to get coswct & sinwct waveforms, I had to run the VFO at… Continue reading Si5351 Clock Generator Programming