I would not check the voltage on the rectifier tube filament, if that is what your speaking of. The voltage there is several hundred volts, and *deadly*. Even if you could measure it, it wouldn't tell you the condition of the rectifier. The high voltage will be on all the pins. That tube changes the high voltage AC, to high voltage DC. Way to risky unless you no what your doing, and have a good high quality meter capable of handling the high voltage there. Plus you would need a schematic for, and understand it.
When does a 5V4G/GZ32 have to be replaced?
Hi all, this is my first post here, and I would appreciate some help! :)
I have a custom made pre+amp built on 4 triodes and a 5V4G rectifier. The triodes are relatively easy to keep an eye on (I am measuring the cathode current), but what about the rectifier? How do I test whether it is still in a good shape (preferably, without removing it from the socket)? Would measuring the actual filament voltage (that is directly fed from a secondary winding) tell me whether the tube is still alive?
Thanks!
I have a custom made pre+amp built on 4 triodes and a 5V4G rectifier. The triodes are relatively easy to keep an eye on (I am measuring the cathode current), but what about the rectifier? How do I test whether it is still in a good shape (preferably, without removing it from the socket)? Would measuring the actual filament voltage (that is directly fed from a secondary winding) tell me whether the tube is still alive?
Thanks!
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- 15 posts total
I'll to try to give you a little idea, why you wouldn't measure the 5 volts on the filament. There would be the full B+ plus high voltage on it *also*. That is why it is dangerous. Pin 8(rectifier tube) on this Dynaco amp (link below), has the output from pin 8 (high voltage DC ) coming out of it (rectifier tube) to feed the filter caps, and choke for the B+ high voltage. I don't know your amp, but on this one, that it basically where the high voltage for the B+ originates. With the schematic, it would tell the proper voltage that should be there. This amp shows 480 volts after the choke. Risky high voltage. That's why you need to know what is happening, and I don't recommend trying to measure it. Dynaco Mk3 link [http://www.triodeel.com/dynamk3.gif] |
Meisterfloh, Get it tested or just buy a new one.... It would seem to me if the tube were to short you could burn out the 5 volt filament winding or possibly the high voltage winding of the power transformer. The tube is by far the cheaper of the two. http://www.r-type.org/pdfs/5v4g.pdf http://www.r-type.org/exhib/aaa0597.htm . |
- 15 posts total