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Projects Page

Here you'll find descriptions of some of the things that I have built. Quite a lot of them have fallen aside the path of time. This page only covers projects that I still have. After all, they're not much fun without photographs.
Guitar Amplifier.

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.

RS-232 level converter.

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.

FM stereo signal generator.

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.

ZM1040 Nixie clock.

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.

RJ45 UTP cable tester.

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.

Microcontroller driven clock with nixie tubes.

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.

Microcontroller-driven frequency counter.

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.

Regulated bench power supply.

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.

Valved regulated high voltage power supply.

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.

Copyright © 2000-2012 by Onno's E-page         published 2000-11-12, last updated 2015-03-08