A bold new project: to build a guitar amplifier combo, inspired by the VOX AC15 amplifier. It has EL84 (6BQ5) output valves and uses vintage transformers. The amplifier and its cabinet are finished. After 3 months of testing I can say it is working really fine. The sound is good. The vibrato channel adds something special. Leaving a few cosmetic things to finish.
This was a quickie. I needed a TTL-to-RS232 level converter to fix the controller of my defective Seagate hard disk. The converter worked and I was able to save my disk.
I needed a simple test signal to be able to align some stereo decoders. It turned out to be quite simple to build one from a kit by ELV. A compact and practical tool.
I had these ZM1040 nixies lying around for a while. Then on Ebay I found a circuit board and microcontroller to build a nixie clock after a design by nixieclocks.de, Building the electronics according to the ready-made design as very easy. I developed a trick to replace the hard-to-get Mouser pins and build my own "free" nixie sockets.
While I was putting network cabling in my house, I suddenly felt the need for a practical device to test cable runs and cables for shorts and interruptions. I had come up with sequencer on one end and a box with blinky lights at the other. But a problem remained. Fortunately, someone had solved the problem and put it up his website. Then I could build the tester and fix my cabling problems.
I found some information on this clock on an electronics newsgroup. Frank Bemelman, had designed a nixie clock and wrote he was offering a kit. His kit was easy to build and the result is neat, for he is also offering stainless steel plates to make the top and bottom of a case for the clock.
This 2-valve regenerative receiver is a folly, actually.
I built a 1-valve regenerative receiver long ago. I tore it apart because it wasn't working as expected. In 2001, after I found back a few parts, I rebuilt it, and used an improved 2-valve design with 2 tuned circuits. This time, things worked fine.
I read about this design in the ELV magazine around the time I was thinking about building a new counter. It had a good price and performance so I bought the kit and built it.
This regulated power supply originates from 1982. It is a simple application of the μA723 regulator IC. In 2004, I rebuilt it to fix some problems and add and extra meter.
This is an oldie. I built it in 1976. It is probably the only project with valves that has survived a number of removals and the need to clear space in the house.