James May would be proud!

When I was a kid there was a metalwork teacher at school who was a bit weird by the intellectual standards of your average teenager. This weirdness was exacerbated by one of the “cool” teachers Dr Jim, regaling the 6th Form chemistry class with tales of how Mr Metalwork had bought himself a patch of land, was living in a caravan on site and was building himself a timber framed house. This guy’s skill was even greater in that he was having to build the tools to cut the timber to build the house. This included a bench saw driven by a car engine to convert his raw timber into beams and planks. Impressive!

Now that was wasted on me in those days as a spotty oik, but today as an avid fan of Grand Designs, Kevin McCloud would be handing out awards with honours for that effort!

Where’s this going you ask? Good point and we’ll made! I’ve taken great delight in building the tools to make and test stuff as my interest in this field has grown rather than buying commercial off the shelf kit. Before I started playing with radio, one morning I woke up and decided to build a Geiger Counter. You what? Yup, a dyed-in-the-wool rad counting Geiger Counter!

Why? Well I’ve always had an interest in that area of physics and following the Fukushima disaster in 2011 there was a massive drive to provide the residents in the immediate and outlying affected areas with the ability to easily monitor the background radiation levels. A public spirited project then ensued with hundreds of easy build kits being shipped to Japan to help. As the immediacy of the situation dwindled these kit’s became available to others and I decided to have a look. Living on the south coast right next door to the home of the Royal Navy it would be interesting to see what was out there that’d make you glow in the dark! Let’s face it, when the local council sent the kids home from school with letters informing parents that schools now held stocks of potassium iodide tablets “just in case there was an “incident” involving the Dock Yard”, you’d guess that you may get a click or two above average off a Geiger Counter. Let’s face it they don’t run warships on AA batteries or unleaded!

So here is my Geiger Counter, equipped with a GM tube from deepest darkest Russia. You’ve got to love the entrepreneurs of the ex-Sov Block countries. I bet it was boosted from some military warehouse!


I can thoroughly recommend building one as a side project. If you want a go have a look here.

Now as part of this build I needed a reasonably accurate capacitance meter, so invested my money in one of these, from Roman Black.


It is one of the most useful bits of kit I’ve got and was worth the investment over and above the budget end of the market floating around on eBay. I try to look after it! The image doesn’t really do it justice I’m afraid.

So, you can imagine my horror when yesterday, while building my 1 Watter it all of a sudden started billowing clouds of blue smoke which very rapidly turned black and acrid!

James May moment and then some -“Oh cock!”

In my enthusiasm I hadn’t cleared sufficient space on my bench and had dragged the capacitance meter over an unfurled roll of solder which had shorted out the battery terminals on the PCB. To be honest I never realised 9 volts could generate that much smoke!

Thankfully after some very tender care Mr Capacitance meter is back and working.

Morals of the story.

1/ don’t dis your teachers at school

2/ value what you build even if it may appear trivial in the grand scheme of things

3/ keep your work bench clear!