1st timer board install help

Flames1950 · Post by **Flames1950** » Sat Jan 22, 2005 4:15 pm

White wire should be OK, looks like the bias tap.....

clarkydaz · Post by **clarkydaz** » Sat Jan 22, 2005 4:23 pm

yeah, its not pretty but thats all i'm capable of a the mo. is it worth mentioning that the tone control wires are slightly wired different compared to the diagram (again stock)? i was left scratching my head about transformer wires and connections when i couldnt see any more wires left? is the brown ht fuse wire correct?

Dax-The-Ax · Post by **Dax-The-Ax** » Sat Jan 22, 2005 7:05 pm

Send me a good pic of the Tone Controls and the output tube sockets and i'll post em'

Flames1950 · Post by **Flames1950** » Sat Jan 22, 2005 8:19 pm

I'm pretty sure that when I was looking over the pic you've got that the diodes on to the HT fuse was all correct. I am once again sitting where there are no schematics at the moment, but I'm sure I tracked that around when I looked before.

clarkydaz · Post by **clarkydaz** » Sun Jan 23, 2005 12:46 pm

if the right side of the chassis is looking ok up to now, could someone just clarify what is connected to the filter cap UNDER the board? maybe something is amiss there.

dax pointed out in the pic a 10k resistor next to the bias pot may be missing? is this the case?

incidentally, using my bias king it biases as normal

Dax-The-Ax · Post by **Dax-The-Ax** » Sun Jan 23, 2005 1:10 pm

Tone controls and Output Tubes

Guest · Post by **Guest** » Sun Jan 23, 2005 1:19 pm

You have the 2 red filter cap wires correct on the board. The ground wire should go from the filter cap lug to the bottom farthest left lug.

Dax · Post by **Dax** » Sun Jan 23, 2005 1:22 pm

If i were you, i would re-wire the tone controls just like the CD. I had to do this on mine when i converted from a 2204 to a 1987.

clarkydaz · Post by **clarkydaz** » Sun Jan 23, 2005 1:41 pm

hey, dax, thanks for the pics you sent, nice and tidy! point taken on the tone controls. at the filter cap underneath i have
the 2 reds,
1 black from the input,
1 black furthest left on the board
1 black from the tone strip
all at the filter ground point

is that correct?

Dax · Post by **Dax** » Sun Jan 23, 2005 2:06 pm

I think you can put the input grounds on the tone control buss. But that all sounds right. Still no sound?

clarkydaz · Post by **clarkydaz** » Sun Jan 23, 2005 2:19 pm

still no joy. i was hoping it would be something obvious, but i'm running outta ideas now. the only thing left is wiring the tone controls again, and the issue of the missing 10k resistor you pointed out. would this contribute to no sound at all?

Guest · Post by **Guest** » Sun Jan 23, 2005 6:20 pm

George, Gnugear!!?? Where are you??? They are the men to fix the problem!!!

Guest · Post by **Guest** » Sun Jan 23, 2005 6:24 pm

I would take those resistors off the tone controls and re-wire them as i said before. Just put a bright cap on the volume I pot. It goes between the 1st and 2nd lug looking left to right on the volume pot. Usually a 100pf to 500pf cap.

Flames1950 · Post by **Flames1950** » Sun Jan 23, 2005 9:45 pm

The 10K that is missing would simply result in higher preamp plate voltages, you should still get sound. That's not your underlying problem.
Can you measure your voltages for us? Pin 3 on each power tube, and pins 1 & 6 on each 12AX7 tube? Post the voltages, and if you have the voltage chart on your reference CD or instructions compare the voltages you get to the standard readings. That will help us figure out where you've gone awry. Remember that your preamp voltages may be higher due to the 10K that's not in place, but we can worry about that later; you may even LIKE the sound with the higher voltages, who's to say?

Flames1950 · Post by **Flames1950** » Sun Jan 23, 2005 10:04 pm

I've been sitting here trying to jump back and forth between pics of my PTP 50 watt install, the schematics, and your pics, and unless you've got voltages that come up wrong, nothing is jumping out at me.
But I'm kinda with Dax, I can't follow what's going on with those Park tone controls without a schematic, you may have to re-do those in plain old Marshall fashion per the diagrams that came with your kit.
Check the voltages first and post them, if that doesn't pan out them move on to the tone controls.

Metropoulos Forum

1st timer board install help

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