The Amp Garage

I have the skyliner tonestack in my #102 while the tonestack in the SSS #002 is classic. I like both.

Had to look at the data sheet:

1st secondary is:
345-290-60-0-290-345 VAC@200mA

I ordered a PT for a 50W D-style project from Poland last week.

Secondaries were:
345-0-345 VAC @200mA,
3.15-0-3.15 VAC @6A
5VAC @3A
12VAC @50mA

for only 74 €!
Is yours in that range?

Lars

Metalguy,

looks good. Please tell us something about the power transformer. Transformers are always the most expensive parts here in Europe. For the OT you went with hammond obviously.

Lars

Hello guys, Update. The amp is running. Sounds good exept for 2 problems: Reverb: Almost no reverb with send and return pot turned fully up. If I hit the tank I can hear the typical noise quite loud. So it seems that the output transducer and recovery gain stage is working, but somehow the send circ...

This is simply ohm´s law. B+5 =354VDC With a 150k resistor to ground the current running through this resistor is: 354/150000 (I=V/R) = 2.36 mA If you omitted the resistor totally minus 2.36mA current would pass every resistor in the string. With less current running through a resistor you will have...

Maybe this ?
They say it´s original Fender. Not expensive.
For black vox there´s another supplier in Europe. Cheaper than Banzai.

I suppose you have a 150k resistor instead of the FET circuit. You can lift up the voltages in the string by changing the value of that resistor.

Adjusting the dropping string will of course have no effect on the power tube plate voltages. What is the secondary voltage (HT) of the PT ?

Yes, cool.

Stand by "on", otherwise there is no voltage on the plates.

Does grounding here kill the hum ?

edit: Ok, fine.

Please measure the voltages of V3 again.

Especially in the network (4 resistors) and between the 24k and 390R.

Ground from the junction 0,1uF/390R/24k/ (4k7 if the nFB is connected) - kind of "bypassing" the presence/NFB circuit. Is that altering the hum ?

Lars

that was quick...job done..

...computers don´t have tubes

Just to clarify that we´re all looking at the same schematic.

Martin,

I´m afraid at all of the points 1-7...
Marcus grounded the grid (pin7) of the PI.

Lars