Adventures in analog and mechanics.

scratch-build homebrew HAM station.

There is no commercial gear in the shack. The homebrew effort was done in 'bursts' Sometimes I was homebrewing for months in a row in my spare time. But when there was no time or enthusiasm, months went by without any effort at all.

 
                               
From left to right; A all-mode general coverage receiver (0-30MHZ), a smaller but capable all-mode shortwave receiver (1,7-18MHZ) and finaly a 40 M band regenerative receiver.
Most of the projects were scrapped and rebuild, from the bottom up, at least once. So all the projects took years to complete.

                                           Adventures in Analog, Mechanics (and a Touch of Chaos)

Is a book I’m writing about the strange, stubborn joy of building radios the hard way. with coils you wind yourself, circuits you can actually see, and mechanical solutions.

The project is still in progress, with 2 remaining chapters being hammered into shape. If you enjoy homebrew radio, odd mechanical constructions, or learning from spectacular failures, you might like what’s coming.

More updates will appear here as the book takes shape.

The new homebrew hobby started in January 2008 with short wave reception experiments.The picture above is the test receiver setup in my garden shed in the very beginning. Soon I was receiving world broadcasters. The first radio amateurs were received in August 2008. With a long wire, as I had no idea what a 50 Ohm antenna was. I wasn’t even sure what Ham band I was receiving, due to a lack of a frequency counter. My first homebrew oscillator had no frequency stabilisation. Anno 2008 I did not realise that a oscillator needs to be stable. So that day I was very busy retuning. Needless to say that the day after, I could hardly repeat the listening experiment. Numerous searches on the internet for additional information tempted me to improve my short-wave radio, over and over again. Until I ended up with an all-mode scratch-build general coverage receiver. The pictures below are the endresult. It had turned 2022 until I was satisfied.

                                                          Scematic homebrew general coverage receiver.

For many years it was a DC receiver/transmitter with sideband cancelation. However, later on the transceiver was changed in a superhet design based on the magnificent BITX. The superhet has a much better S/N ratio in my opinion.

                    

                            Schematic homebrew CW transceiver.

                                      SUper SImple frequency counter/oscillator stabilizer.

                                                                   Schematic homebrew SSB transceiver.

The SSB rig is a good example of my usual construction method. All circuit blocks soldered in seperate tin boxes that I buy from Amazon. They are all bolted to a aliminium ground plate. So lead inductance is minimised. All circuits are therfore schielded from one other. Also, I do love wood. Many of these boxes are not pure aluminium and can be directely soldered. My prefered soldering style is 'ugly'. Another advantage is that every circuit can be accesed very fast for mods or troubleshooting. There is a history and RF reasons why i build the way I do. More explanation in the PDF below.
 
                                     

Simultaneous a linear was build. At first I tried to build a 50W linear with multiple IRF510s, pfff. Probably it can be done for one band (but when you try it multi band a lot of explosions occur) Eventually a very expensive RF MOSFET (MRF510) was bought to do the job.  

                                                             Schematic linear with MRF150.

Holiday shortwave receiver.

The antenna I use is a homebrew loop. The diameter is 1,6M and tuning is done remotely with a DC motor. The butterfly high voltage capacitor is made with the plans of ON4CEQ as a guideline. The loop was chosen to stay on good terms with the neighbor's which is more important to me than my hobby. In case you ever dought that such a small antenna can be any good. Below the results on RBN after calling CQ on 40/30 and 20M, for 10 minutes, with 5 watt.

                                                                       Motor control for loop antenna.

There is also a RX 5 to 29 MHZ indoor magnetic loop. The upper band have opend somewhat since 2024 but I am not sure if it is worthwhile to build an TX magnetic loop for 17, 15, 12 and 10M...

                                                         The RX magnetic loop antenna above.

Another homebrew project was a FM/Airband receiver. In 2010 I saw a “Make” article on how to adjust a simple FM radio to receive the Airband. I was more ambitious and salvaged ICs from cheap FM radios from our local scrap yard and tried to build completely from scratch. That did not go well and could not make it work. Only by 2014, after I used tin cans for the RF circuitry the radio worked. Tin cans rule!

                                                                                               Schematic homebrew FM/Airband receiver.

In hindsight, I made a lot of detours with all sorts of circuits and components. My conclusion is that the BITX schematic is relatively easy to build for the average homebrewer. You can base nearly every type of rig on it, and it is simply unbeatable.

Since 2008, when I started listening to the short wave bands a lot has changed. Only one MW station left… No more BBC world service…No more world broadcasters… only the lower Ham band remain active. When I listen in most of these guys are well into retirement. Soon the Ham bands will be quiet to , I guess…

But I had a lot of fun, I might try vacuum tube stuff before the bands become quiet... Because I don't have a clue how to build a tube station I just might relive the joy of homebrewing. In fact, I started a quest for an all tube regenerative shortwave receiver in the summer of 2024. This turned out to be very difficult. Slight elektrocutions and smoke were the only concrete results in the beginning. My respect for the HAMs in the 1920s and 1930s has grown!

                                            

Due to the setbacks with the tube regenerative radio I figured to build a solid state regenerative receiver as an educational project in 2025. It was dificult build but it turned out fine! The receiver is based on one of N1TEVs designs. The radio works well for such a simple circuit. Sensitivity  is amazing, however, selectivity is not to modren standards. I could add audio filters for CW and SSB which would pull the radio up to the level of a good DC receiver but I am going to leave it as it is.  And experience the full 1920s experience.

                                                        

                                 Homebrew one band regeneration receiver

Later on I did succeed in building a tube regenerative receiver. I just works well enough for a 40 M band SSB QSO. I is defenately my wurst radio but boy is it fun. It lets you realy relive the 1920s.

                                         

                                                       homebrew tube regenerative reciever










Below are 2 circuits to stabilize Oscillators but they are replaced by the SUSI circuit as I find it superior to a Huff and Puff and more fun than a PLL....

2-The original SSB oscillator was an all-band H & P oscillator. Below a link to a PDF file describing my quest to build a oscillator stabilized over a wide range of frequencies stabilized with a H&P. First part is how (I think) an H&P actually does the job, second part is an account of the experiments. Along the way I discovered what works and what does not work and a method to lock a H&P on any frequency. At the end, the actual multi band H&P oscillator, for the transceiver, is presented. Its is a pretty long PDF...

                                                                        An all band H&P stabilized oscillator.

                                                                   On1mws. [email protected]