These are the equivalent resistors #s on Eric's new PCB/schematic for negative rail.
R105=241mV
R110=245mV
R112=234mV
Beautiful!
i would like to take the full credit, but i have to split the compliment with the cnc
... loud look for me.
At this point all the MOSFeTs have been replaced and several of the 270ohm resistors. Still no change. I'm not sure what I'm getting crazier over; trouble-shooting this PCB with no positive results, or our US election and the aftermath in the news non-stop. I'm a bit of a political junkie too!
R110 seems to have one "leg" not soldered... or at least, seems you used some sort of paste that doesn't flown correctly...
maybe is worth a double check
I checked it and re-touched both ends. It's good. Believe me, I've re-checked every solder joint, and re-touched a few that looked suspect. I'm baffled and it's rather discouraging not to make some progress on this despite all the great suggestions and help here. I'm very meticulous about my builds, and usually adopt the, 'check thrice, solder once' approach .
.I am afraid I am running out of suggestions except for a bad part.
Given the 3 CCS and the current limiter look OK according to your measured values, I would change Q108 mosfet and perhaps the BJTs of the shunt part.
The passive resistors doesn't need to be changed if measured OK.
Couple of remark.
1- 100k in The BOM or it is 1 K. https://www.diyaudio.com/forums/pass-labs/277355-ugs-muse-preamp-gb-48.html#post6073054
2- What is the connector between the source triggers and the amps Triggers. (not in Triggers BOM)
3- The SUB board is different from the original. P15 is 5x2 socket in the Rear and left boards and 4x2 in the Sub Board ( 4x2 right angle header).
1- 100k in The BOM or it is 1 K. https://www.diyaudio.com/forums/pass-labs/277355-ugs-muse-preamp-gb-48.html#post6073054
2- What is the connector between the source triggers and the amps Triggers. (not in Triggers BOM)
3- The SUB board is different from the original. P15 is 5x2 socket in the Rear and left boards and 4x2 in the Sub Board ( 4x2 right angle header).
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▶ 100k - confirmed ✔
▶ there isn't one in the bom because there is NO connector between the two, already asked couple of posts ago, you just need to wire trough the holes once they are mounted and solder them as is. I would suggest to solder first all the wires (solid core is advisable) from the side with the IDC 90° connector, then feed them trough the other board and solder them in place.
▶ same doubt, not even bothered asking. for what i understand, the additional couple of pin are good for future "expansion" for another type of sub board. for the one in the GB just justify the connection to the only possible border.
2, link wire, cutoffs from resistor’s or caps, cat 5/6 cabke with no insulation.
3, you can still fit 5x2 in the left / right rear PCB’s and not use all pins or you can fit 4x2 just make sure in correct holes