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Old 5th March 2004, 06:13 PM   #1
Netlist is offline Netlist  Belgium
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Default Another Fender on the bench.

Looking at the schematic: http://www1.korksoft.com/~schem/fend..._100_schem.pdf at V5A, V5B I measure some strange values.
1) 364
2) 39.5
3) 0

6) 309
7) -39.5
8) 0

I measured all resistors surrounding the tube and replaced it with the 7025s. I tried several of them, V1, V2, V4, same result.
The only cap I changed was the 5 uF at pin 8, with a 4.7F.
What could be wrong?

Thanks
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Old 5th March 2004, 08:09 PM   #2
Netlist is offline Netlist  Belgium
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Sorry, wrong schematic: It should be the 135W.
http://www1.korksoft.com/~schem/fend..._135_schem.pdf

So why is the 1.8V and the 12V missing on both cathodes?
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Old 6th March 2004, 07:15 AM   #3
SHiFTY is offline SHiFTY  New Zealand
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Sounds like the tube is not drawing any current, has it lost the ground connection or the cathode resistors gone bad?
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Old 6th March 2004, 08:03 AM   #4
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Thanks, I forgot to connect the vibrato pedal. When on, the tube turns on as well.
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