Following the original by JF3HZB (PW October 2022 p56) I have bodged mine sort of based on the original https://github.com/tjlab-jf3hzb/Digital_VFO_with_analog_dial https://tj-lab.org/2019/02/17/vfo5/ I will use for bench signal source and an older direct conversion radio setup I have. The ESP32 I used seems to be a bit different. The upload speed 115200, 240MHz, 40Mh flash, 4MB flash Anyway programmed it. I used a 2" rotary controller as per the PW article. Ruler and JLCPCB squeaky duck for size comparison ..read more

 This is tiny. Amazing bit of homebrew. The manual is in Japanese but the block diagram explains how it works  nifty bit of engineering with the case (3D printed and bent acrylic sheet). The PCB doubles up as support of the OLED and the uPC and battery charger are on separate PCB underneath. The components are gnat shite size though! This is some nice homebrew. Looks like they are building some more... Just fitting battery. Mine is 180mAH so lot smaller than original. Small battery fitted working at just 80grams, this will be a good one for /p operations for sur ..read more

 I have this printed out as I refer to it often enough so I reproduced it here (I cannot recall the original source tbh but all the values are on several reference books anyway) I got loads of torroids from GQRP club sales and W8DIZ. The  different material works at different frequencies.These are often used in common mode chokes and wide band baluns. Material Common mode choke frequency range (single turn) Common mode choke frequency range (multiple turns) Impedance transformer 1:1 Balun (Choke) #31 3,5 - 100 MHz 1,5 - 50 MHz - 1,5 - 30 MHz #43 25 - 600 ..read more

Postie delivered an old part built project, but a very good one. Feels like an eternity passed looking for a replacement for one I sold in error. I was about to loose hope as spoke to Steve KD1JV and he didn't have anything from the original (very old) project left. I must backup that AVR processor read the HEX off it (not an attempt to clone etc) before it gets used ..read more

Going to be trying a few other SDR. Raspberian OS and compiled on the RaPi4 (before putting into RASPAD3). RX only. SDRPlay (version 1) RX and TX. Lime Mini and Adalm Pluto (the second if I can find where I put it last as the box is empty!) I use an external USB 3.0 powered hub with these. I expect will also try the DragonOS for the RaPi as well. I have an SDR and an HF upconverter (basically an RTL dongle) so you can sample down to about 50Hz is needed, will try that was well. This had already been tested by David Taylor https://twitter.com/gm8arv and the developer https://twitter.com/cemaxec ..read more

   Will turn this into SDR thing tomorrow.  I compiled the SDR++ and GQRX for the RaPi4 yesterday ..read more

 Installing GQRX and SDR++ on RaspberryPi These are all the steps I actually performed. sudo apt update apt list --upgradable sudo apt install gqrx-sdr rtl_test -t gqrx So GQRX sort of worked... So SDR++ Grab the source git clone https://github.com/AlexandreRouma/SDRPlusPlus.git ls cd SDRPlusPlus mkdir build cd build/ cmake .. so erroring as missing these packages....fftw3 glfw glew libvolk so to install them... sudo apt-get install freeglut3 sudo apt-get install freeglut3-dev cmake .. sudo apt install libglew-dev cmake .. sudo apt install glfw3 sudo apt install libglfw3-dev cmake ..read more

Last weekend I built myself a nice Pi 4 system for the shack. Everything worked perfectly, but todays as I rebooted the Pi would simply not boot up. Usually I run almost all my Pis in a headless enviroment but as this is the desktop for the operating position I had monitors connected. Lo and behold, there it was, The Pi would get stuck at boot with the following error message "Cannot open access to console, the root account is locked." The error message while not too descriptive, it asked me use sulogin and run journalctl -xb however there was no shell to run or list anything. I thought oh ..read more

I had these in the workshop and as not operating right now, thought what could I make with these and a few other RFy things from the 'junk box'. Well I know  have some SA612 and SMD op amps and lots of SMD discretes so thought might try the EU1KY analyser, after looking at JA versions (but seemed to miss out on the kitting as was sorting Mum's stuff out for Dad). The STM32F746G-DISCO board in a blister pack, with a H7 version too, has been in the junkbox for a bit. I bought a couple of the Front end RF PCB a while back for the EU1KY. I have a few SI5351 modules with 25MHz crystal so ..read more

It is definitely not new, and I claim no originality as this idea has been posted elsewhere before, but I mentioned in discussion that I was using this (along with octoprint) on my Raspberry Pi 'servers' used with the 3D printers and CNC between Cambridge and Cornwall, 400 miles (and when really remote on some DX trip, usually to tweak some SDR setting) to adjust stuff if needed. Sounded really useful so  I was asked could I provide some details: So here goes (your mileage may vary so don't assume a pure cut and paste will work for you). There are plenty of albeit old guides out there tha ..read more