The Amp Garage

If it's a linear pot, then yes. If it's a log taper, then the response->rotation will be wonky.

An easy way to test for a linear pot is to center it and measure the resistance from center to each end, it should be approximately equal.

...and unless you're in a _really_ rural location, the correct answer is almost always 125.

I've always been a fan too, but cable ties are so much easier, lol.

Hard to say for sure without knowing what U7 and T3 are.

This Hammond AO-63 amp does not have any cap before the choke. It also has a tube rectifier. I agree with the previous poster, the small value cap in the newer design is really only useful there to reduce HF noise. OTOH, as you get up to 1uF, you start to have a (really weak) cap input filter. I gu...

If buy in sufficient quantity, F&T will brand the caps for you.

To amplify a bit, 151 = 15 plus 1 zero = 150. Based on the type and size the 150 is in pF.

Yeah, little high gain antennae.

I think R.G. is onto something. I put a 250 ohm 25w resistor across all three combinations, and read 3.2vac (again) on one, but the other two now read almost nothing (0.007xx vac). These three wires are the only "8 amp" (6 x EL34) sized wires coming out of the transformer, so they must be the heater...

There is very low resistance (< 1 ohm) between the three big wires.

You'd have to ask Sound City.

The upper HT winding is ~250VAC and the lower is ~325VAC (both no load).

Here's the 'left hand' side of the schematic fwiw

I have a Partridge PT supposedly from a SC200, and the secondary windings and voltages it mostly check out as expected - but the three big wires (black, blue, green) coming out of the secondary, which one would assume are the heater winding, measure ~62VAC across two pairs and ~3.1VAC across the oth...

Thanks for the suggestions

I have to re-tube a DR201 (6 x EL34, 650v B+). What are folks experience with current EL34 brands in a higher voltage situation (besides "boom!" )?

The 201 has a split supply, so the screen voltage is about 2/3 the plate voltage, which helps a bit.

All good information, thanks