[Amps] Resistor Types

[Peter Chadwick]

Manfred said:
>Yes, this is of course a point to keep present. It would never occur to 
me to make a series string of different diodes, and use them without 
equalization! But for that matter, I wouldn't use a series string of 
different diodes at all, not even with equalization!<
Fortunately, it's not usual (at least in my experience) for just one diode in a series string to go. But losing a string that's part of a bridge is another matter, and some  people may feel all they need to do is change that string. Under those conditions, I'm a believer, like I gather Manfred is, in changing all the diodes.
At least with silicond diodes, we don't get the problems we had with mercury vapour, where they could occasionally arc for no real reason. One trick was to put a small coil in each plate lead witha piece of steel rod in it it: after the flash over, the steel was magentised, and you detect it with a small compass needle. That told you which tube to change......
73
Peter G3RZP