Introduction About 20 years ago I was building various SDR receivers and I needed a signal generator to test their performance. I decided like most hams to build my own using the latest Analog Devices 8 bit DDS chip AD9850. The unit was controlled by a simple Atmel ucontroller, was battery powered/portable and worked up… Continue reading HRF1 as a Signal Generator for Amateur Radio

Introduction Recently I discovered the NanoVNA vector network analyzer. I had seen articles in QST magazine over the last several years and was intrigued (Ref.1/2). I remember years ago testing VHF/UHF/uW antennas with large signal generators, directional couplers and scopes all weighing hundreds of pounds. Now the same thing and more can be done with… Continue reading HF Antenna Testing with NanoVNA

Introduction Continent Call Sign Location Locator North America VE8AT Inuvik, NWT, Canada CP38gh 4U1UN UN, New York, USA FN3Øas W6WX Mt. Umunhum, CA, USA CM97bd KH6RS Maui, Hawaii, USA BL10ts South America YV5B Caracas, Venezuela FJ69cc OA4B Lima, Peru FH17mw LU4AA Buenos Aires, Argentina GFØ5tj Europe OH2B Lohja, Finland KP20eh CS3B São Jorge, Madeira IM12mt… Continue reading RTL-SDR for HF Beacons

Introduction In previous posts I examined using GNU Radio to receive various signals such as VOR, VHF Air Band, SSB, AM, WBFM, AIS and ADS-B (Ref.1). I also examined how these signals could be simulated using Scicos (Ref.2). In many cases for testing purposes, we need to capture a sample of the signal in question… Continue reading RTL-SDR for RF Signal Capture in GNU Radio

Introduction Recently I started to experiment receiving satellite weather from NOAA15/18/19 (Ref.1/2). I decided to see if I could do the same thing with the Raspberry Pi4, since this would add yet another functionality to a compact and efficient platform (Ref.3). Tracking Software For tracking, we can use Predict developed by John Magliacane KD2BD (Developer… Continue reading RTL-SDR for NOAA Satellite Weather on RaspberryPi4