Author Archives: Jan

Si5351 VFO

By | October 5, 2023

Here is an older project of mine – another variant of a VFO. This time with the popular Si5351 clock generator, allowing to create a complete solution for a superhet, including both the VFO and BFO oscillators.

VFD hacking (again)

By | October 24, 2018

Three years ago I have posted an article about reverse engineering a large surplus VFD module that had no documentation available. Well, it is time to do some more hacking! I have attended the HAM radio meetup at La Louvière, Belgium this year again. Lot of people, lots of all kinds of gear there but… Read More »

Termination Insensitive Amplifier (TIA)

By | November 5, 2017

I have needed some RF/IF amplifiers for my receiver, so I have decided to use the design by Wes Hayward, W7ZOI, and Bob Kopski, K3NHI, originally published in 1999. This amplifier has two main advantages – it has a wide bandwidth ant it lacks any tuned circuits, so it is easy to use in a multiband… Read More »

DigiTIA receiver

By | March 27, 2017

The guys at the Solder Smoke podcast have inspired me to do a bit more solder melting and this is the result – a CW/SSB HF receiver for 40m band. It is a bit “al fresco”, with no case, built on a piece of copper clad with modules stuck down using a double sided tape. The rig… Read More »

AD9850 VFO II

By | March 22, 2016

It has been some time since I have posted the article on building a simple VFO/signal generator using the AD9850 module and a microcontroller, originally based on the work Richard, AD7C. I have received quite a bit of feedback from several people, along with a few requests for improvements to make the hardware more suitable… Read More »

VFD hacking – VFD 240W.401

By | March 28, 2015

The recent video by David L. Jones from the EEVBlog on VFDs has inspired me to look in my junk box – I knew I had an old VFD in there. By old I mean really old – I have bought it around 1999-2000 in Munich from an electronics surplus store, along with a few… Read More »

AD9850 VFO/signal generator

By | February 22, 2015

22.3.2016 UPDATE – if you are looking to build a radio VFO, there is a newer version of this code available, with more radio-oriented features. I have started to play with amateur radio again and wanted to have a decent VFO/signal generator that could cover most of HF without complicated part switching required. So I… Read More »

How some vendors ship chips

By | January 10, 2015

This is what I have just received from AliExpress – pair of SSD1963 display drivers. Packaged in a cut-off piece of the plastic tray and wrapped – in a plastic foil! I understand that an anti-static bag is more expensive, but this is ridiculous. I do wonder how many returns because of ESD damage does… Read More »