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CitizenCain
06-28-2008, 05:24 AM
OK, I have my Heathkit conversion amp all wired up and I'm ready to fire it up and check some voltages. I was going to do it with no tubes just to check node voltages and make sure nothing blows up.

However, the amps I've worked on before have had diode rectifiers. This one has a tube recto. I'm sure I know the answer, but I need to at least have the rectifier tube installed in order to get anything to measure, correct?

Just checking on the obvious :o

tubeswell
06-28-2008, 05:58 AM
You can fire up theh amp without a rectifier tube in it first to see if your'e getting an A/C from the sec windings.

Then (switch of off and) plug in the rectifier and see if your'e getting a B+ - the voltage will measure higher than normal because the other tubes aren't in there to load it down.

If you've got a B+, then (switch if off again) and plug in the rest of the tubes and watch the inside for a while to see if anything catches fire/smoke comes out. :p

The measure the other tube voltages and calculate output tube dissipation satisfy yourself that the output tubes are not running too hot.

Then plug it in and start trouble shooting for other unwanted aspects (such as DC on the pots, weird oscillations, hum etc)

CitizenCain
06-28-2008, 03:50 PM
Thanks for the informative answer, tubeswell! Wish me luck!