George Brown

Electronic Engineer, Hobbyist, Radio Amateur

Nixie Tube Experiments

I recently purchased a set of 12 IN-12A (ИН-12А) nixie tubes from Russia. I was eager to try them out and make sure they survived the trip. For this I built a very basic high voltage power supply to fire them up, and then got a bit carried away! This article concerns the use of a relatively high voltage supply. Stay safe when working with high voltage, and do not proceed until you are comfortable with the required precautions.

HP1652B Power Inlet Repair

A few years back I bought myself a HP1652B, that’s an 80 channel logic analyser, with a two channel 100 MHz scope inside too! (Not bad for £150 eh?) In this post, I’ll cover the repair I made to the unit after it suffered a rather exciting failure. The Fault I’d been using the thing for a few months, until one day it went up in a cloud of very stinky smoke.

GPS Vehicle Tracker

I frequently cover large distances by car, be it visiting friends or moving to work or university. At the moment it seems I can’t go very far without arriving at some part of the country disrupted by Smart Motorway upgrades, horrible peak time traffic, or something else entirely! I’m normally well equipped to deal with such hold ups, however without the ability to contact people while on the road, I can’t let them know where I am.

2m Tape Measure Yagi Antenna

Through the first half of 2016, British astronaut Tim Peake was aboard the ISS. During this time he carried out a number of 2m FM voice contacts with schools.. For the first few contacts, I used a Baofeng handy with a 2m whip antenna, which worked quite well for listening in, but it was not ideal. I also tried using my very basic \(\frac{1}{2}\lambda\) antenna. This didn’t seem to work much better, and I was starting to notice some pager interference coming in too.

125kHz RFID Tag Reader

As part of my course’s labs, we had to design a RFID reader board. This project served two purposes; it let us use the skills learned in our communications system lectures, and also gain practical experience in PCB design. This project was done in partnership with Harry Beadle. The board is designed to operate with 125kHz tags. These have been superseded by 13 MHz ISM tags for most modern applications. 125kHz is still the standard for animal chipping though.

Building a Website in Hugo

For a long time, I was running a webserver that served up a few handwritten HTML pages. I’d used the Bootstrap to try and make the content a bit prettier, but it was never that great. In addition I was rarely able to add content, since writing HTML is a relatively slow and boring process. My friend Harry Beadle showed me how he’d started writing his website in markdown, using Jekyll to convert the files into a complete website.

Thermal Decapping

During my A-Levels my chemistry teacher started up an element collection. As a leaving gift, I felt it would be good to provide a sample of perhaps the most important element in electronics to the collection. Decapping ICs to extract their silicon goodies inside is an often discussed topic on electronics forums. The epoxy of a standard DIP package is remarkably strong and resistant stuff. An often documented method is to heat the device in a puddle of nitric acid.