Tube Amp Archive

any price range is ok, it will be my main tool so reliability, spare parts availability and perfect functioning.... price isn't important

Of course but it can happen that some components can be charged just enough to short the soldering iron.

from what I understand I'd be looking for a weller or hakko with the ceramic element type that would isolate the heater from any HV present inside tube amps.... is this correct? If so can anyone link me up to soldering stations that have this feature? All I can find are single soldering irons. thank...

well it seems as though you were right with all tubes in the all the tubes light up properly and B+ is around 325vDC. The bias mod? I truely think that adding the cathode resistor is pretty useless since all the measurements have to be taken with the circuit board mounted inside and that means the r...

Yes well looking at the schematic the LV section that also feeds the bias supply does send off the heater voltage before the BR. I will do another checkup tomorrow but I'm fairly sure that I followed the bias mod correctly wiring the 3 wires to the right place and replacing the right jumper with the...

well as I said above, the only way to test the voltages is without the tubes in, and I'm getting correct reading for everything except the heaters that seems to be completely absent. There aren't any filament wires coming off the PT as one would expect, I think that the LV windings before the rect.b...

http://blueguitar.org/new/articles/blue ... 0_mods.pdf

scroll down to page 35

actually I just tried putting all 3 preamp tubes in and the heaters light up very faintly on all three. what's going on here?

Peavey classic 30 1995 model, put in the bias mod shown here: http://blueguitar.org/new/articles/blue_gtr/amps/peavey/c30_origmod.pdf I did follow the advice about the 1watt 1 ohm resistor replacing the jumper instead of cutting the trace. Bias voltage is there, b+ voltage is there and LV is there b...

I separated the primary wires from the secondary, but that didn't change anything, however I did notice that if I turn the mains plug around, the swooping phase effect on the volume disappears, even though the backround noise is still there, atleast the volume pot seems to work properly. What could ...

Well I tried moving those 2 resistors to a ground point, and tried the amp in a grounded plug and sure enough there was that noise, as I turn the volume up it gets louder and after 3/4 seems to sweep into another frequency. When assembling the amp I did cut down the 4 and 16ohm secondary wires to ar...

Well all this doesn't really answer my doubts, if I use the amp in a non grounded plug, it's quieter and doesn't give out that low frequency hum... similar to when you touch the tip of the guitar lead. If I use the amp in a grounded plug... that hum is present... I only have used 2 ground points - 1...

Those 2 100r resistors are soldered together on pin 8 of the 6L6 tube. I have wired both directly to the heater terminals on the power transfomer. It's more or less the same thing (following your instructions) if I just unsolder them from pin 8 and solder them to a common ground point making sure th...

I've noticed that the original champ schematic has pins 1 and 2 on the power tube joined together and grounded, should I do that too? here some photos of the kit:

Well resoldering the wire to pin 8 fixed up the squeal, but I'm getting an even stranger problem now. My lab doesn't have grounding atm and the amp seems to be much quieter, just giving that classic noise when turning up the volume. If I try the amp in out recording studio where ground is present, t...