Test Equipment

I like old test equipment (especially valved equipment), and have a small collection of it. I find mantaining the test equipment is often just as much fun as using it; except when to solve a small problem I find one piece of equipment is broken and I reach for the scope to fix it and then find that that doesn't work either, and before I know what I'm doing I'm off on a chain test equipment fixing marathon!

My most interesting piece is probably a BC221 heterodyne frequency meter, built for the american air force during World War II. It has alas had the valves removed, but I'm in the process of putting them back.

Marconi Equipment List

Marconi test gear dating from the valve era in general seems to have been built to a very high standard and often survives to this day in working order. The same cannot be said for the manuals. Hence I've been compiling a list of such equipment with details of ranges, and applications. The list started off from one in the back of the RSGB publication on Test Equipment for the Radio Amateur by Clive Smith (G4FZH); but it's been added to in light of the equipment which I now own.

HP Equipment List

With HP numbers as annoying as Marconi ones, this list also aims to covert HP part numbers into real life descriptions of the equipment. More annoying still with HP is their habit of using non standard part numbers for perfectly standard components. These are usually to be found in the 1820 series. Fortunately some chips have both an HP number and a real number on them, and some service manuals give both. Hence a list of equivalents can be compiled.

Xerox Equipment

Xerox have a similar annoying habit of relabelling ICs, some equivalents may be found in this rather short list.

Integra Potentiometer

A schematic drawn and (badly) scanned by me of this early design of potentiometer is here. It was designed for measuring temperature in a portable way when combined with a thermocouple. The instructions are amusing in that they suggest `Cabling for a replacement' should the galvanometer break. It is currently broken, but I doubt cabling would be of much assistance.