Whether the meter drops when you drop voltage read depends on how leaky the cap is. Here is a bad way to test a cap, but a good way to see how the tester reacts. https://youtu.be/6E_qKxD2wDw. This is a better procedure but the test isn’t quite as stark. https://youtu.be/WlwSexqRRWg

I have a dead meter from a TO-6, with a good face. It's here somewhere, I just have to find it, if you're interested. I replaced the whole meter with a Simpson TV-3.

Older Thread .... but I just came into a 6A and wondered if anyone happens to have the calibration procedure. BAMA has everything but, as apparently calibration was not part of the normal ops manual like it usually was...., and some web searching hasn't turned up much in the way of calibration instructions.

I can fake it by using what I've got and my experience from the 4 and 6 ... but always like having the correct stuff.... and no, I have not yet tried to figure out what the difference is between the 6 and the 6A. If I have to, I will

Thanks!

I am working on restoring a TO-5A. A couple of guys here put together a TO-5 theory and functional guide, pretty detailed - 30 pages. Not really much difference in theory between a TO-5 and a TO-6. Someone else assembled a TO-5/TO-6 calibration guide.

These may help.

John

Thanks KX5....I've got the Mike Higgins writeup up on my site, and will add this as well. I appreciate your finding it. I may also do a detailed comparison between the TO-6 and TO-6A, since I"ve got both of them here right now. Stay tuned. I think I may also have a TO-4 around somewhere...will check and if so add it as well, although I believe it is much different from the 6

One thing that I found when reworking my TO-6 is that the unit may not be exactly the same as the schematic; I had one resistor that was absent, and another one was a different value. Evidently, they were tweaked during initial calibration.