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I'm trying to determine if my rectifier tube is bad, or is it the power transformer? I'm getting 300 VAC on pins 4 & 6 of my 5AR4 and B+1 measures 350Volts. I've new filter caps and new resistors on the all the caps in the dog house. Any ideas? I do not have a tube tester. Any help would be appreciated. If it's not the rectifier, I guess the power transformer? Funny, I had higher than normal voltages on V1 pin 2 + pin 6 and so on up the circuit., now it is lower than normal, 180, should be 210. I have a Super Reverb. thanks and Happy New Year!!
Asked by Anonymous on January 3rd, 2018.
We are not techs and can not help you troubleshoot your amp. The best thing to do is take your amp to a qualified tech.
5AR4 rectifiers are direct filament rectifiers. When they get old, their output voltage takes a hit. That isn't true for transformers. Either they work or they don't an open winding on a tranformer means you get nothing, zip, nada. A shorted primary on a transformer means the transformer hums like a harmonica and quickly overheats and self-destructs. A shorted secondary on a transformer will lower the output, but that is so rare, I've never seen it. I've been a service tech for 50 years. If I've never seen it, it may not even exist. Theoretically, it can happen. If that's what you've got, it will be the first time.
Will this rectifier tube replace a full wave rectifier In a fender pro sonic?
Asked by Anonymous on February 13th, 2017.
If your amp calls for a 5AR4/GZ34 then these should work. I would consult your manual or examine your amp to see what type of rectifier tube it has in it.
I have a Fender Vibrolux amp. Want to change the 5u4gb with a 5ar4 rectifier. Will it be ok?
Asked by Anonymous on September 28th, 2017.
According to our tube substitution handbook, the 5AR4 is not a substitute for the 5U4GB.