Tube Amp Archive

Reeltarded wrote:Instead of swapping caps, add one in parallel that adds up to the value you are looking for with an on-off single pole switch.

Simple and that works.

I like this; so, switching caps in parallel won't cause the problem I had before?

I had decided to replace the caps in my Bassman clone with PIO K40Y-9's. I did some digging around the net and found out about the discrepancy between the 5F6A schematic and some of the production models (i.e., the 100k slope resistor, the .1uf bass cap, the 25k dc-to-ground presence pot, etc). Give...

I think the top of that pot (clockwise lug) must be shorted to ground then. Well, I didn't *see* a short ... but to be on the safe side, I just went through and re-soldered every joint on the board and the tubes that was part of the signal chain. Must have either had a cold joint or something going...

martin manning wrote:An easy way to check it is when the signal has been lost, jump the clockwise and middle lugs with an insulated tool like a small screwdriver.

Tried it. When I short the lugs, the signal dies entirely.

You mean the treble pot right? All of the preamp signal passes through that pot, so if the wiper fails to make contact with the element you lose the signal. Did you disturb that pot in any way? Herp derp, yes. Treble. Edited to reflect that ... Not that I'm aware of, but I'll double check the conne...

Hey folks, I have a weird issue and was looking for some assistance ... Recently, I had to replace the filter caps on my 5F6A due to it blowing fuses. The filter cap replacement solved the problem, and the amp is running again, but something bizarre started happening: the Treble knob, when turned up...