[TestSubject]

 
Quote:

When I am the ruler of the world you can be my head negotiator. 

I can be sure of one thing, I wont be responsible of the technology advancements committee
 
EDIT: on a more serious note, all resistors match both side of the circuit.

 

[nikongod]

That's a bummer. Measured from the furthest points? Tube socket and stuff. 
 
Measure the plate resistors to the positive voltage rail (power off of course)
 
Have you tried switching tubes from one side to the other? Its possible you have a bad tube. 
 
After that, its all about checking voltages. 

 

[TestSubject]

Have not checked the furthest point on all of them (did all the grounded resistors), but the sockets all check up. Will remake some test first thing tomorrow morning.
 
 

Measure the plate resistors to the positive voltage rail (power off of course)

 
I am sorry I am not sure I understand.
 
I have switched the tubes and both seems to work.
 
About Voltages, Digger945 suggested i sampled voltages between pin 4 and 5
 
 

One Channel measure 19Volts between pin 4 and 5 while the other 27 Volts...

 
Thanks much to both of you for helping me out! Of to bed now.
 

 

[nikongod]

Quote:

 
I am sorry I am not sure I understand.
 

 
Measure resistance from the positive voltage supply line (with the power off) to pins 1&6 on both tubes. 
 
measure resistance from the gate (input) of the mosfet to the positive voltage line and ground. 
 
Measure resistance to ground from pins 8&3 (should all be the same) and pins 7&2 (also all the same - 7&2 should vary as you spin the volume control)
 
Measure as much as you can from the tube pins. This is key. Measuring just the resistors does not tell you if you skipped a solder-joint, or accidentally shorted something.

 

[TestSubject]

Okay after one more day of going through the circuit, i found a missing jumper, Ho boy I was happy, but one channel still doesnt work.
 

 

pins 7&2 (also all the same - 7&2 should vary as you spin the volume control)

 
The non working channel shows a significantly smaller resistance. Exemple, 2.7k while the other is around 12.2. However they both read 1k when pot is at one of its extreme
 
EDIT: all measurement are done without the tubes plugged in.
 
Thanks again

 

[nikongod]

 
Quote:

The non working channel shows a significantly smaller resistance. Exemple, 2.7k while the other is around 12.2. However they both read 1k when pot is at one of its extreme
 

Do the values change correctly as you spin the volume knob? 
Measure them with the volume knob at every quarter or third of its rotation. for a 50Kohm pot it should be something like 1Kohm (volume all the way down) 2Kohm@1/3up, 10Kohm@2/3up, 50Kohm@max volume. Those are very rough numbers, from my head. Your results could be 50% different, but they should go something like that.
 
If the dead channel goes up to 2.7Kohm and stops, where the live channel keeps going up past 12.2Kohm this is something I would investigate. It sounds like you accidentally shorted the grid of the tube to the cathode, but thats a wild guess. To confirm this guess measure the grid-to-cathode impedance with the volume knob at max volume. It should be ~50Kohm.

 

[TestSubject]

Okay, the non working channel does indeed stop increasing at 2.8K
 
However the working one, at full volume, it displays 28K
 
What on earth is going on...
 
EDIT: i checked, they are in sync until 2.8K

 

[nikongod]

Do you have 50Kohm (or so) resistors across the input RCA's, not shown on the stripboard? that would explain why the good channel only goes to 28Kohm. 
 
What does the resistance from grid to cathode look like with the volume knob all the way up?

 

[TestSubject]

 

Do you have 50Kohm (or so) resistors across the input RCA's

Yes I do, sorry for the un-complete design
 
Between Pin 2 and 3, the working channel reads: 30K were the other reads: 1K
 
EDIT: as always, measured with no tubes in
 

 

[liamstrain]

Same thing when you swap tubes? 

 

[TestSubject]

I am afraid so.

 

[nikongod]

I'm totally sure you have a short somewhere. 
 
My guess is that the 1kohm resistor between the grid(input) of the tube and the pot shorts to the strip that goes to the cathode on the side closer to the pot. It may also be where the pot wires to the board on that same strip. Flip the board and check there. 

 

[TestSubject]

I am very sorry sir but I need to go now, the amp sound so sweet to BOTH of my hears I really have no time to say thank you.
 
 

Spoiler: Warning%3A%20Spoiler!

After taking the Amp apart 4 times, and resoldering many times, I may have shorted the input to the cathode.

 

 

[nikongod]

Cool! Glad its working. 

 

[TestSubject]

Everything is in place, will be taking shots soon.
 
I have one Mosfet heating more then the other. I really hope the heatsinks are big enough, I mean they are hot! The datasheet say 175 Degrees but...
 
EDIT: After putting a droplet of water on the Mosfets, the water evaporate, they are running over 100 degrees...
 
REDIT: Note that both tubes are not the same model, might explain the difference?
 
Also buzzing and clic-ing in the background at about 2/3 of the Volume.