FIXED-Volume only on 0D channel but nothing on clean channel

[jcsifu]

So I just rewired my high plate into a low plate keeping the sky liner EQ. When I first tried the amp the clean channel worked but the OD channel was lower volume and basically clean. After Chopsticking around and reflowing some joints, I am now left with only the OD channel. I must say that it sounds really good, but I don't understand why in a cascaded amp the clean channel does not work. There is continuity on all the pathways that should be there and all grounds have continuity to the chassis. I will check voltages more thoroughly tomorrow and post them in this thread. I don't recall the exact numbers as I was just checking for basic readings, but I think I remember the readings were off on pin 3 of V1 or V2. The voltage was 1,4. Both tubes had around 190 V1 and 200 V2 pin 1 and 6 as they were before. I won't have time until the Sunday to build an audio probe and test. Now I'm having a hard time going to sleep because it baffles me and it's all I can think of, so I was hoping someone had a similar situation or a guess as to where I should aim on Sunday. Does anyone have any ideas on what could cause no volume in the normal channel but not affect the OD?

[10thTx]

Does anyone have any ideas on what could cause no volume in the normal channel but not affect the OD?

relay DPDT faulty wiring

With respect, 10thtx

[Structo]

Also check the front panel switches and make sure they are correct as well as the rear panel manual switches.

[jcsifu]

Does anyone have any ideas on what could cause no volume in the normal channel but not affect the OD?

relay DPDT faulty wiring

With respect, 10thtx

I was wondering if I had a bad relay while thinking about this last night I bet your right on the switches, i didn't look at the schem when I wired them up. just took a look before.

[jcsifu]

Also check the front panel switches and make sure they are correct as well as the rear panel manual switches.

Ok, will do

[jcsifu]

10thtx:
So I re did wiring on the xlr jack to make it cleaner and ended up replacing the switch for OD/Clean when I re did that wiring. I'm embarrassed to admit it but I could not figure out how to apply the switch drawings that you posted so all connections are done as the OTS layout specifies. I still get no sound when foot switch is switched to clean but OD I do. I am posting the layout in hopes that you would see if my fatal flaw might be obvious. I don't understand how the switching works, and I think that is what is keeping me from getting to the answer. I have worked on mostly fender amps in the past, this is a whole diff beast. Does this diagram seem right to you?

respects,
JC

[jcsifu]

Also check the front panel switches and make sure they are correct as well as the rear panel manual switches.

Everything seems fine on the front.

[ToneMerc]

Does this diagram seem right to you?

JC

Without discrete details and pictures it's like flying blind when trying to help.

In theory, just a plate conversion would only involve changing V1&V2 plate and cathode resistors and maybe increasing the cathode cap values on V1, This work is local to the main board and should be transparent to any switching.

What relay boards are you using?

Was it working perfectly before the conversion?

Did you disturb any jumpers under the main board? Verify continuity between the V1A plate and slope resistor.

TM

[jcsifu]

Without discrete details and pictures it's like flying blind when trying to help.

I apologize, I will post pics as soon as my little niece leaves tonight.

In theory, just a plate conversion would only involve changing V1&V2 plate and cathode resistors and maybe increasing the cathode cap values on V1, This work is local to the main board and should be transparent to any switching.

Exactly what was done, only change was that I only had bipolar 10uf caps on hand for the bypasses on V1, that's the only thing that will change when my parts order comes in.


What relay boards are you using?

Not sure, but they are the ones Nick installed originally as this was purchased used and was assembled by ceriatone. There were some little fixes that needed to be done because the guy I bought it from was trying to work on it but quit, so I bought it at a low price.

Was it working perfectly before the conversion?

Yes, it worked with about a year of gigs and practices under it's belt as a high plate. This is why I don't understand why this is happening.


Did you disturb any jumpers under the main board? Verify continuity between the V1A plate and slope resistor.


I'm wondering about this, I decided to replace a lead that was cut too short to lay with the other leads as a 124 would have that goes from pin 6 of V2 to junction of 150k and .005 cap. I checked continuity on this area and all is well. I will go in and check other underboard leads tonight as well

I will check continuity tonight as soon as my little niece leaves, I have everything put away until she and her mother leave so house is safer for her to roam and play.

Thanks TM

[ToneMerc]

Without discrete details and pictures it's like flying blind when trying to help.

I apologize, I will post pics as soon as my little niece leaves tonight.

In theory, just a plate conversion would only involve changing V1&V2 plate and cathode resistors and maybe increasing the cathode cap values on V1, This work is local to the main board and should be transparent to any switching.

Exactly what was done, only change was that I only had bipolar 10uf caps on hand for the bypasses on V1, that's the only thing that will change when my parts order comes in.


What relay boards are you using?

Not sure, but they are the ones Nick installed originally as this was purchased used and was assembled by ceriatone. There were some little fixes that needed to be done because the guy I bought it from was trying to work on it but quit, so I bought it at a low price.

Was it working perfectly before the conversion?

Yes, it worked with about a year of gigs and practices under it's belt as a high plate. This is why I don't understand why this is happening.


Did you disturb any jumpers under the main board? Verify continuity between the V1A plate and slope resistor.


I'm wondering about this, I decided to replace a lead that was cut too short to lay with the other leads as a 124 would have that goes from pin 6 of V2 to junction of 150k and .005 cap. I checked continuity on this area and all is well. I will go in and check other underboard leads tonight as well

I will check continuity tonight as soon as my little niece leaves, I have everything put away until she and her mother leave so house is safer for her to roam and play.

Thanks TM

No worries, I just wanted you to clarify exactly what you were working with. In essence, it worked perfectly before you made the plate conversion, so that narrows the scope down a great bit. I would verify continuity verses the layout first. If that doesn't work then post some pics and we can put more eyes on it.

You're welcome

TM

[jcsifu]

Will do, pics to come soon

[jcsifu]

Just finished checking and I have continuity as per the layout.

I took these pics earlier today, when looking at them I noticed that the OD top 2 poles were connected and it was not like that in the layout. So after snipping that gap I tried the amp out again. There is no sound still out of the clean channel. There is sound out of OD but it has a nasty distortion when a note is picked hard. So...

When doing the switch to low plate, I only had bipolar 10uf 50v or 10uf 150v in hand, and I just went with the bipolars. Could those caps be the culprit? Should I switch the 150 volts ones in? I think I will do that tomorrow night and see.

[10thTx]

So I re did wiring on the xlr jack to make it cleaner and ended up replacing the switch for OD/Clean when I re did that wiring. I'm embarrassed to admit it but I could not figure out how to apply the switch drawings that you posted so all connections are done as the OTS layout specifies. I still get no sound when foot switch is switched to clean but OD I do.

Since your input jack goes to V1-2 and not V2-2, then your clean channel must be working when you get overdrive. You can verify that clean is working by using jumpering from the V2 to the LTPI bypassing the switches and relay.

IF that works and you then get a decent clean sound, then you know the problem is the switching so that is where you will concentrate your efforts.

With respect, 10thtx

[jcsifu]

Since your input jack goes to V1-2 and not V2-2, then your clean channel must be working when you get overdrive. You can verify that clean is working by using jumpering from the V2 to the LTPI bypassing the switches and relay.

IF that works and you then get a decent clean sound, then you know the problem is the switching so that is where you will concentrate your efforts.

With respect, 10thtx

Awesome! I'll try that tonight and post back. I really appreciate your time here 10thTx. The 183 diagram really shows what is happening with the relays.

[10thTx]

I apologize because I wrote the idea out incorrectly in my previous post.

Jumper from V1b to the LTPI. (I stated V2 incorrectly in the previous description).

The schematic and layout drawings should be correct and show the V1b to LTPI jumper.

With respect, 10thtx