Taylor 45C Pot A replacement (my experiences)

[Fourlegsgood]

Having got fed up with a temperamental Pot A on my Taylor 45C valve tester I thought I would have a go at sorting it.

The first thing I noticed having taken the front off was that it was not an original potentiometer. It looked like a cheap wire wound 2k2 . Attaching a multimeter showed the problem to be a random set of resistances around the first 30 degrees of travel (ie the resistance jumped all over the shop rather than changing smoothly).

I tried cleaning but it didn't help.

There seem to be several threads on here asking about this pot but I couldn't see any definitive answer except that is is definitely a 2k pot and not the 2k2 one that was fitted.

So anyway, I have jumped in where angels fear to tread and fitted a 10 turn 2k wire wound pot (5w).Obviously if one is testing a large number of valves the 10 turn could get a bit tiresome but I don't test a huge number of valves. I also noticed that for the valves I usually test it wasn't taking much rotation of the knob before K got to the X mark with the 1 turn pot. I hoped the 10 turn would help with this.

The result of fitting the 10 turn pot is highly satisfying and works perfectly. It's now easy peasy to get the needle dead on the X without it jumping all over the shop.

Result!!

Nick