Sunn T continuity issues, hum no signal even in true bypass

[Anonymous]

Hi everybody, wondered if you could help me with my model T build, I have poreviously built a few pedals but was needing a preamp for my mobile rig which is just a solid state power amp to cover for my Matamp gt120 but doesn’t weight 20 kilos ha!
I’m having a few issues with this im not sure what I’ve done wrong exactly, when I’ve checked for continuity acroiss the board these are the ones without.

Looking forward to hearing back from the hive mind, apologies if I’ve missed something in the troublkeshooting guide, the board is definitely getting 9v I’ve checked that, the JFETS arent getting any voltage I’m getting some reading in hundreds and thousands that keeps varying but no beep.

Please bare in mind I’ve never used a multimeter before so this is all new to me.

Pots 1 and 5 grounded

Pots 2 gain 3 gain brt, 4 bass and 6 treb not connected to ground, no continuity

R1 no cont
R7 no cont
R6 no cont
r10 no cont
r2 no cont
c1 No cont
C9 No cont
c12 no cont
c7 no cont
c2 no cont
c9 no cont
c4 no cont
c5 giving reading in hundreds, dont know what it means
c10 no cont
TR2, TR3 no cont

JFET Legs are giving the same kinds of readings in hundreds and thousands but don’t undertsnad what it means when checking the voltage of the jfets im getting 0.1 – 0.2 when going from drain to ground

I resoldered everything on the board apologies if its a bit messy, when doing this I had gotten wire stuck in some of the terminals and couldn’t get it out so soldered directly to the surface of the contacts to the wires.

Will upload some photos in a few seconds.

[Anonymous]

I’m not sure how to attach photos on forums so here’s a link to an album

 

https://photos.app.goo.gl/2aDLF1p7zBSpJpBG6

[Cybercow]

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[Cybercow]

To be brutally honest, the wiring looks quite unstable. The insulation needs to butt up against the PCB where the wire goes thru the PCB. I can only guess that all the exposed bare wire is coming into contact with the edges of the enclosure – based on the photos.

[Anonymous]

Hey man, I agree to be honest. The issue was there was no info about the jfet boards as I’d never came across them before so didn’t have the foggyest what to do with the boards. I’ll just order another kit when I get paid and start again.

 

Cheers anyway man, have a great weekend.

[Author]

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