Volume issue wit TD Deluxe

[Oddvar R]

Hi. Just finished my take on the Tweedle Dee Deluxe, everything worked from the beginning, except that the volume seems to be to low for this amp. Any tips on where the an issue like that may occur?

[erwin_ve]

Hi. Just finished my take on the Tweedle Dee Deluxe, everything worked from the beginning, except that the volume seems to be to low for this amp. Any tips on where the an issue like that may occur?

This is like asking,; Where's the needle in my haystack. No disrespect Oddvar; you need to give more than that for troubleshooting. Pics, voltages etc. would help.

[Oddvar R]

I get that, but I was hoping for a first check point. The volume seems to be at full reaching 4 on the pot, But all pots function. The sound is very overdriven, like an overdrive fro the start.

V1/V2 (Pin) 1-141v 174v- 3- 1.073v 1.5v, 6- 145v 228v.
6V6 (pin) 3- 319v, 4- 360v, 8- 18v
Filtercaps: 362v-320v-275v

Compared to the numbers on the layout: 21.58v -16v, 256v-228v, 199v-174v, 267v-253v, 172v-145v, 173-142v.

I am using two RCA 6v6gty tubes and two 12ax7's.

I have checked all resistors for value, and they seem to be ok, as do the caps.

[pdf64]

...V1/V2 (Pin) 1-141v 174v- 3- 1.073v 1.5v, 6- 145v 228v.
6V6 (pin) 3- 319v, 4- 360v, 8- 18v
Filtercaps: 362v-320v-275v

Compared to the numbers on the layout: 21.58v -16v, 256v-228v, 199v-174v, 267v-253v, 172v-145v, 173-142v...

That’s a really confusing way to present the numbers.
So what’s the cathodyne’s cathode voltage?
Dunno if a TD uses a cathodyne

[Oddvar R]

V1/V2 numbers are pin 4/3/6. 6v6 numbers are pin 3/4/8

The last number compares to the ones on the pic.

I wonder if the pots can have anything to do with volume issue. How are they supposed to act? The two volumes seems ti interact, turning off one turns off the other and vice versa?

[pdf64]

V1/V2 numbers are pin 4/3/6...

A properly presented voltage survey in a table format please (as per Marshall example), or you're just taking the mick.
https://el34world.com/charts/Schematics ... pchart.gif

[Oddvar R]

And I was wondering about the pot here, what is it for? Is it some kind of NFB or what?

[martin manning]

And I was wondering about the pot here, what is it for? Is it some kind of NFB or what?

See discussion here: https://ampgarage.com/forum/viewtopic.p ... 11#p418311

[Oddvar R]

And I was wondering about the pot here, what is it for? Is it some kind of NFB or what?

See discussion here: https://ampgarage.com/forum/viewtopic.p ... 11#p418311

I read that, thanks, so that's sorted.

What isn't sorted is the volume issue. I have changed the pots, measured every voltage and resistor, nothing seems to be unusual. So what could possibly be the reason for the low output?

[pompeiisneaks]

As was asked by pdf64 earlier, the voltages you posted are really unclear. Can you use a common chart like he linked to show us what measurements mean specific things?

~Phil

[Oddvar R]

Here is a rough voltage draft.

[pompeiisneaks]

Seems you're missing one of the nodes, B+4, either that or the B+3 voltages seem a bit low, so that might be b+4 instead and one of the earlier ones is missing.

Note the schematic shows expected estimates of B+:

https://ampgarage.com/forum/download/fi ... &mode=view

but at any rate, that does seem to show a possibly significantly lower voltages on B+. That might make it quieter by a little. but I don't know by how much. it lists the output post rectifier should be almost 400VAC, then after that first dropper about your noted 360VDC so that's a 40V difference.

Another process you could try would be to inject a known signal into the input, and measure AC volts after each gain stage to see if somewhere it seems to go down/lose signal. In this amp, the first two triodes of V1 each handle a different input, so that will depend on which input you're using, but the outputs go to the volume/tone network before going to the first half of the recovery triode in V2. Then the other half of V2 is the PI. if you can find somewhere that the signal seems to suddenly drop out, that will help.

Usually I see mV of AC signal in the grid, and then a volt to maybe 5vAC after the first gain stage, etc, if you don't see that constantly increasing in every stage except the V2A where it's recovering from the tone/volume losses, then you have at least an area to research.

~Phil

[Oddvar R]

B+4 is 249.5v. It's the junction between the fourth 33uf cap and the 10k cap?

[Charlie Wilson]

Pictures of inside the amp? Clear ones please for tired eyes. Also, what power transformer gets you a B+ of362v with a GZ34?
CW

[Oddvar R]

This is the Power transformer.