Fender bassman 100 Help

[stevek66]

I've got this Silverface Bassman 100 That I changed filter caps in for a friend.It worked before I replaced filter caps.I started it up with a bulb limiter and everything was ok.I put in preamp tubes and fired it up again with bulb limiter,everything fine.Next I added powertubes and then bulb limiter stays pretty bright and none of the tubes light up.I've got about 380 volts on all the filter caps.I haven't changed or even touched anything else.Any clues or help in what I might look for?

Thanks in advance Steve

[CaseyJones]

I've got this Silverface Bassman 100 That I changed filter caps in for a friend.It worked before I replaced filter caps.I started it up with a bulb limiter and everything was ok.I put in preamp tubes and fired it up again with bulb limiter,everything fine.Next I added powertubes and then bulb limiter stays pretty bright and none of the tubes light up.I've got about 380 volts on all the filter caps.I haven't changed or even touched anything else.Any clues or help in what I might look for?

Big clue "A": It worked fine before the cap job so I'd be lookin' around those new caps first. Is everything kosher in that area?

Red herring "A": NONE of the tubes light up?! That's frickin' HORRIBLE! That's horrible 'cuz the filaments are a seperate winding from the B+. Does the pilot light light up? If it doesn't that's a leading indicator you just blew the PT.

If the pilot lights see where your filament doesn't have continuity.

[stevek66]

Hey Thanks,
The jewel lamp does light up.I will look were you suggested.
Thanks Steve

[stevek66]

I just checked heater wires come off the jewel lamp.1 side I get 6 volts the other side I get like 0.020volts. hmmm.It 's frustrating..

Thanks Steve

[stevek66]

If I turn it on with just pre-amp tubes,they light up.If I add power tubes none of them light up.

Steve

[CaseyJones]

It sounds like you're o.k. so far. Make sure you haven't accidentally pushed the preamp tube socket lugs together.

Shorted 6L6 maybe? Stick them in one at a time. Measure voltage across your filaments. If it drops with one particular tube we have a winner. Umm... make that a loser 'cuz that one's a dud.

[stevek66]

hey thanks for the input.I have all tubes lit now but volume is whisper quite and nasty sounding.When i plug in the bulb limiter and start adding tubes the bulb limiter gets brighter as i add tubes.So still a problem somewhere.
I get 6.3v on heaters
1st 100uf 216v
2nd 100uf 440v
3rd 20uf 438v
4th 20uf 417v
5th 20uf 365v

Thanks Steve

[stevek66]

hey thanks for the input.I have all tubes lit now but volume is whisper quite and nasty sounding.When i plug in the bulb limiter and start adding tubes the bulb limiter gets brighter as i add tubes.So still a problem somewhere.
I get 6.3v on heaters
1st 100uf 216v
2nd 100uf 440v
3rd 20uf 438v
4th 20uf 417v
5th 20uf 365v

Thanks Steve

[CaseyJones]

Please accept my apology... when we get into "low and distorted" it's a relatively simple fix with the amp right in front of me and a guessing game without it.

[stevek66]

Please accept my apology... when we get into "low and distorted" it's a relatively simple fix with the amp right in front of me and a guessing game without it.

Hey CaseyJones,
I appreciate all the help you gave me.I got it fixed.
Sometimes you can look at something till your blue in the face,and you just got to walk away for awhile or ask for help.
Thanks again Steve

[Structo]

I would try all new tubes if I were you.

Coincidences do happen.

One time on my D'Lite I had tweaked a few components.

Fired it up and no sound. WTF?

Was just about to tear out the OT when I thought, I wonder about that speaker cable?
Yep, I had used an old Marshall speaker cable with molded ends and it had an open in one end.

Probably stressed the OT but I really never turned it on for long.

Got a new cable and got sound!

Then one of the TAD 6L6 tubes redplated.....
Related?

Who knows but I replaced them with some Winged =C='s and all was well.

So even if you didn't make a mistake don't throw the baby out with the bath water.

It could be something that went buh bye on it's own.