Help on new #40 build

[andresound]

Thanks Martin,

That was an earlier pic. Realized I had made that error and changed those two. Part of the error's I picked up "after going through the wiring for the 1000th time"

I am going to call it a night. in the morning;

1. I will re-wire the Fx loop as you have shown. Does the big .05uf cap in the Fx loop (presently coming from the wiper of the front panel master level pot), become redundant? Don't see one in your schematic! That Master Level wiper will now have to go to the PI entrance as shown originally. There is another (dammit) error of mine!!
2. Go over the way the relay was wired. I dont recall a "click" of the relay when I hit the front panel switch! (does the little LED on the relay, light up when engaged?
3. Have a strong cup of coffee!!

Thanks again for all the time you have invested in this project

[martin manning]

1. I will re-wire the Fx loop as you have shown. Does the big .05uf cap in the Fx loop (presently coming from the wiper of the front panel master level pot), become redundant? Don't see one in your schematic! That Master Level wiper will now have to go to the PI entrance as shown originally. There is another (dammit) error of mine!!

I don't see the logic in that Normster loop with the front panel master used as the send level. The way I drew it in makes more sense to me. No need for any more caps than are shown.

2. Go over the way the relay was wired. I dont recall a "click" of the relay when I hit the front panel switch! (does the little LED on the relay, light up when engaged?

I believe that's the idea. Measure voltage across the coil terminals and see if anything happens when you engage the OD. If that's not working then I'd check the relay supply voltages and wiring carefully. It can be hard to hear the relay pull in.

3. Have a strong cup of coffee!!

For sure!

[andresound]

Morning guys,
Herewith rewire of the Fx loop and relay.

Still volume is very soft. However, if I take tout the send jack to a power amp, I am getting really good cleans and a WIDE range of tones via the tonestack and switches. This section of the amp (barring OD, something connected wrong here!), is operating beautifully. Also surprisingly quite (no nasty hum etc.)

Problem is when I engage the relay for OD, the sound is muted . Have checked the relay and it is operating correctly. Will go over again

[martin manning]

At least the re-wire hasn't moved you backwards. A common problem that causes loss of signal is a stray bit of shield touching the center conductor's solder connection. With the OD engaged, measure resistance to ground at the clean out/OD in and OD out to see if it's something like that. Is there a possibility of a solder bridge to ground on the relay board?

[andresound]

At least the re-wire hasn't moved you backwards. A common problem that causes loss of signal is a stray bit of shield touching the center conductor's solder connection. With the OD engaged, measure resistance to ground at the clean out/OD in and OD out to see if it's something like that. Is there a possibility of a solder bridge to ground on the relay board?

No shorts to ground on coax's was hoping there was!

[andresound]

The relay, when engaged, connects clean exit to OD entrance and OD exit to your "A" (send entrance) simultaneously. Is this correct?

[martin manning]

Yes, correct.

[andresound]

At least the re-wire hasn't moved you backwards. A common problem that causes loss of signal is a stray bit of shield touching the center conductor's solder connection. With the OD engaged, measure resistance to ground at the clean out/OD in and OD out to see if it's something like that. Is there a possibility of a solder bridge to ground on the relay board?

With OD engaged the is no resistence to ground (my FLUKE meter jumps from 22 meg to 42 meg to open circuit.

[andresound]

Yes, correct.

When un engaged, these two connections are open. correct?

[martin manning]

You should see something besides "infinite" resistance. The OD input has 82k to ground, and the OD output has 180k to ground per the schematics. If you don't get that in clean mode, then the ground is missing.

This OD relay set-up leaves the OD input and output floating when OD is not engaged. The later circuits grounded the OD input in clean mode.

[andresound]

1) After rewire of Fx loop, decided to try a line level into return jack. Nothing, zilch, nada

2) Noticed with pre out into a power amp, (in clean mode), if I turn up the OD, it effects the sound. Introduces noise.

3) Did some voltages of FX and PI tube

FX pin 1 = 250
pin 2 = 16.2
pin 3 = 30.75
pin 6 = 230
pin 7 = 30mv ?
pin 8 = 1.67
PI pin 1 = 275.4
pin 2 - 67.5
pin 3 & 8 = 105.9
pin 6 = 273
pin 7 = 68.2

[Colossal]

I believe there is an error here.

Andre,

I am late to this party, but please see the attached drawing. I'm not sure where you are with the relay board, but as you had it in the photo, it was incorrectly wired and all OD signal was going to ground.

[andresound]

Welcome to the party Dave./ Be warned, its a little depressing.

The realy board pic was an early one. Being reticfied since. See below.

The "output to Level pot" is now going to pin2 of send ("A") as drawon by MARTIN. Hope this makes sense.

[andresound]

You should see something besides "infinite" resistance. The OD input has 82k to ground, and the OD output has 180k to ground per the schematics. If you don't get that in clean mode, then the ground is missing.

This OD relay set-up leaves the OD input and output floating when OD is not engaged. The later circuits grounded the OD input in clean mode.

On my Shematic, the OD entrance has a 100k to ground. Are you refering to this? Should the amp be powered up when doing the reading?

[andresound]

Rechecked. The OD section is definitely ground from the tied 1.5k+5uf to ground.