Sorry, I don’t think I’m understanding the instructions. I took the meter and put black probe on ground at power supply board and the red probe on the v+ of the output vfet board and those were the readings I got.
I built it 2 years ago so I don’t remember the solder brand, maybe Kester? I think my temp on the iron was pretty high.
I built it 2 years ago so I don’t remember the solder brand, maybe Kester? I think my temp on the iron was pretty high.
Re-check meter settings. DC volts. Can't measure over 36.
With power off you should be able to measure continuity between all the "G" connections on both output boards and they should all read zero ohms. Then you can measure DC voltage (with power on) between any "G" and each V+ on those OS boards.
With power off you should be able to measure continuity between all the "G" connections on both output boards and they should all read zero ohms. Then you can measure DC voltage (with power on) between any "G" and each V+ on those OS boards.
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Sorry everyone, I’m nursing a bad flu while I try to pass the time on my 5th day homebound 
I meant to write 35.3v and 33.5v. Do you see any poor soldering, is that what you mean? There’s continuity between all grounds.
I‘m perplexed on why both sides measure close to the same but one side is generating heat to the touch and the other is not? They are both biased to 14v.
Thanks again for the help.
I meant to write 35.3v and 33.5v. Do you see any poor soldering, is that what you mean? There’s continuity between all grounds.
I‘m perplexed on why both sides measure close to the same but one side is generating heat to the touch and the other is not? They are both biased to 14v.
Thanks again for the help.
pictures are showing very bad soldering job in several places, especially on PSU section, but logically to expect similar job done on amp pcbs itself; expect because we can't see underside on pcbs
best approach - dismantle channel from heatsink, resolder everything
there is some crucial point on circuit without contact, most likely
post pictures of channel pcb copper side
anyhow, it would be best to re-work soldering job on entire amp
best approach - dismantle channel from heatsink, resolder everything
there is some crucial point on circuit without contact, most likely
post pictures of channel pcb copper side
anyhow, it would be best to re-work soldering job on entire amp
Pa did with boards what was necessary to ensure specific VFet being exactly biased
as far as I remember, that was placing output parts, source resistors, opto and few surrounding resistors
rest was to Greedy Assembler
see pics here, especially those in post #8: https://www.diyaudio.com/community/...-pt-2-n-channel-assembly-by-mighty-zm.385977/
Coulda sworn my OS was fully assembled and tested in my kit, but it's been awhile. If this one was soldered by OP, that's a flag.
There are probably many good soldering tutorials on this site, but here's a quick vid. To (finally) address fumes I recently added this instead of an expensive fan and foam filter, FWIW.
There are probably many good soldering tutorials on this site, but here's a quick vid. To (finally) address fumes I recently added this instead of an expensive fan and foam filter, FWIW.
Thanks everyone for the insight and help. I’ll resolder everything and check connections. It‘s definitely a mistake on my part. I received the kit from the lottery pick so everything came together and the OS boards were already assembled. When I built it a few years ago everything worked fine and played well; I did something that messed it up or bad soldering degraded with age. I‘ll spend time this week going through it. Thanks again for the help.