Oops.. 5f6a.. zap

[Lindz]

measures 10k (9.56) but creeps up to it for a couple seconds from about 4k. Not sure if that is unusual in the board. Measuring across the resistor itself also creeps up when it is in the board whereas that same 10k on the bench pretty much reads 10k instantly

[martin manning]

The drift is expected, that is your meter charging the caps. The resistance to ground sounds about right, but that is not consistent with the zero voltage reading when power is applied. You had something like 120VDC on one side of the 10k and zero on the other, right? And this is true with the preamp tubes both in and out?

[Lindz]

Replaced the 10uf cap and voila.. I have voltage

Either the cap was bad or some soldering was that I fixed when installing

Loaded tubes and all seems ok in terms of the limiter dimming though it does dim a bit after the initial flash but then seems to take maybe 15 seconds after that to dim down as much as it is going to. Flash coming off standby dims immediately

But now I have another dumb limiter question - Should I have sound (i.e guitar through the input jack) with the limiter inline? I don't, at least with the 38 watt bulb I have in it. I'm still gunshy about plugging straight into the mains in case I do indeed have some wiring issue that caused the fireworks before.

I do get some noise from the speaker when probing for voltage from the power section up to v3 but v1 and v2 do not make any noise when probing with my meter - seems when I am working on my other amps I tend to notice some subtle crackling noise.

I am measuring 225v b+ and about 60v AC with the limiter inline and the amp idling,
225v on the plates in power section
208v on v3 pin 6 and 182v pin 1
210v v2 pin 6, 186v pin1
166v and 171v on v1

Power tube filaments glow dimly, but preamp tubes I cannot see any glow though there is about 1.6v AC on the heater pins

Is there simply not quite enough voltage on the heaters or elsewhere with the small bulb in the limiter for me to hear some gutar or should I be chasing some other issue?

[Lindz]

Was out buying cat food and thought I would pick up a bigger bulb.. my supermarket had 72 watters so loaded that in the limiter and that seems to be enough voltage to get sound

Was trying to get a 100 but I guess in this day and age of CFL's and LED lights the old incandescent type are out of style

With that in the limiter it seems like everything is working and I can hear guitar - stoked.

I guess I answered my own question about minimum voltage needed ...

Also seems like my initial mistake when I blew it up before was indeed patience and stupidity as it seems firing it up with no load did in my OT.. dummy. Does not seem to be any wiring issues other than that cap and I am not so sure I did not zap that when I had my initial fireworks

[Lindz]

Fired it up on regular AC - thought I had a problem as there was some buzzing but it turns out to be caused my lights on the workbench and an open chassis

BTW - I have not played a 5F6A Bassman before - seems like the bass and mid tone controls have no effect (or very negligible) - is this normal or should I check my wiring? Treble seems to work fine

[Lindz]

one leg of slope resistor with suspect soldering... reflowed and all is good now

[martin manning]

Great! Looks like you have recovered nicely!