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Topics - batbob

#1
Hi all,
Thanks for stopping by this post, I hope you find it interesting and can offer me some advice to get this bad boy working.
It was working a year ago and it's not been played since, turning it on this week and it produces a loud hum in the 4x12 cab or headphones.

The schematics are attached and I have worked my way through them to try and track down the problem, without the aid of signal tracers etc..

The guitar plugs in and in clean channel 1 you can hear nothing but the hum. in channel 2 (Warp) the only time you hear guitar is when maxed out on the Gain and Master.

If phones are in FX Send socket it sounds like the preamp and all pots and channel switching works, you can hear the effects of the pots etc so I think it must be post-preamp and in the poweramp section somewhere.

I've checked power supply for all voltages as per page 3, all good. page 2 bottom, right to left, all voltages are spot on too.
I've removed lots of the resistors and capacitors too to check them

The issue appears to be in the poweramp stage so I changed the two large power transistors  T5 (TIP142) and T6 (TIP147), checking the removed ones with a DMM on diode setting shows there are no issues. I changed them for some off the web, but they were smaller in size and when I powered up with these and then R66 released some magic smoke and then the transistors no longer checked out correctly.
I put the original TIP's in and replaced the 39ohm R66 and I'm still having the same issue.

Can anyone see anything obvious that I'm missing? I've checked for dry joints and have tested all resistors, some caps, some diodes but I think I need advice now on where to narrow my focus into from people such as yourselves who might recognise the symptoms and immediately have a suspect component.

Any help will be massively appreciated and I thank you in advance for your time and support.
#2
Shematics I picked up from the web in anticipation of fixing a Warp 7 head.
I'm going to be asking for some advice in the Amp troubleshooting forum too, I can't sort it out..
If you're able to I'd love you to come and take a look at my question and offer some help.