Marshall DSL HELP !

[Valvehead]

I have a DSL 100 here, it had a shorted power trans. I just got a replacement , and Im having trouble with the secondary.

The main pcb in this amp is a JCM2-60-00 .

Looking at the scem , my 2 HV lines should be connected to W5 on the main pcb , and W10 (goes to the standby) on the ac/power in pcb . I think ??

the old stock trans had 5 wires on the secondary, white/black/ white were bunched together--i think this is my bias.

2 red wires--i am pretty sure those are heater (i have the new trans hooked to those on the pcb and i have proper heater voltage right now)

then 1 yellow that goes to the ac pcb

1 purple that goes to the main pcb, right next to what i think is the 4 diodes for B+.

My problem is, i am clipping my 2 hv wires from the new trans to W5 (main pcb) , and the other to W6.

amp is ok on standby, but when i took it off standby... my current limiter lit up , then the power switch rocker flashed..and i smelled something burning..... i shut it off of course.

so-- im trying to figure out if i have the HV wires in the wrong place ??? if not , there must be a shorted component somewhere ?

Can someone decipher the Marshall scem ?

[Enzo]

Rather than interpret the schematic, identify the primary winding, connect mains to it, and VERIFY the voltages on all the secondries. Don;t connect them to the amp until you are sure of what each is.

[Valvehead]

yes sir---all test good hanging in the air. I now have the heaters connected = all good.

[Valvehead]

Whats confusing is , i have 2 scems, jcm2-60-00 , and jcm2-60-02 , and the amp has connections that agree with BOTH .

I just tried the following with the HV wires--- i am bypassing the power sw to eliminate it.

connect to w5 and w10. w10 went to the old trans secondary-it goes through the 1A fuse, then to the pcb at w6.

also tried connecting the hv wires to w5 and w6 on main pcb. Either way--when i switch it on , my current limit bulb lights up and i get a spark at R74 . R74 tests ok by the way.

Looking at the jcm2-00-02 scem....my hv wires should go to the standby sw and W7, yes ?? it shorts that way.

Wondering if i have a shorted component down the line--after all something took out the original power trans

The amp did have a shorted / arced/burnt power tube socket. I replaced it and the pcb is clean in that area

[93DMTX]

valvehead,

Don't know if this will help you or not but I have a 2005 vintage 100. It has an issue 7 main board which and I've always used the JCM2-60-02 schem for it.

My notes are:

Bias Supply
============
PT white -> W13
PT white -> W11

Ground
===========
PT black -> W12

Heaters
============
PT red -> W10
PT red -> W11

HV
===========
PT Purple -> W7

Pink W6 -> AC Module

Doug

[Valvehead]

yes---im trying to hook the hv to purple and pink. read my post above for the results

[Valvehead]

I think I found my short !!
I took a closer look while powering on...right where r74 was sparking... This resistor has big 1/8" wide "legs" . The very corner of the leg was sitting right on the very edge of a trace . I bent the leg over a bit, and behold....no short. Amp seems to idle normal now....but I have not hooked up the bias wires or ran it with tubes yet.

[Valvehead]

Well--its all wired in and the amp is back to life. But.....my luck strikes again---the OT is fried. Amp works great but acts like it has only 2 watts......and yes i tried using the fx send/ret with another amp = no luck.

[AmpFix]

Hopefully this helps. Check this page out:
Marshall DSL Transformers
There's a picture of a PT and OT with the wires connected to the main PCB.

The Heaters go to W9 and W10. The HT goes to W7 and the switch. W11, 12 & 13 are for the 22-0-22 taps.

[Amp Kat]

Did you ohm out the OT from blue to red and brown to red and blue to brown ? You should get around 18 ohms aside and about 32 across. If you tried the send out and it doesn't work that doesn't sound like an OT problem it sounds like a preamp problem.