Personally I never really put Loctite back on the screw heads. It sure can't hurt unless you put on way too much. Add in loctite once your 100% happy with the amp and you are done trouble shooting. Looking at this example in the pics it looks like an excessive amount of loctite, so much that it dripped down on one of the transistors. Looks very sloppy... A silicon based heat sink compound is easily found at Radio Shack. I bought a big tube of it on mouser and it will last a long time.

Wow that's a lot of Locktite!! I have been inside many Crate amps and have never encountered one having that much Loctite.

Yeah actually I did work on an RG80 before and removing all the pots was the way to go for me. Sometimes other wires can come loose while getting to the underside of the board to do the soldering. Double check all other wires before putting it all back together or you could end up repeating this if you notice a loose wire later. When you don't free up the pots the three wires to the board can get loosened. I also found it much easier soldering on the board with it freed up. I actually replaced all the wires that were on all the pots as the wire was old and needed it. The older wiring in these amps tends to break off at the board pretty easy. Good luck :tu:

Edit: I was posting just as you were and was mentioning the old wires on the pots... Either way you go about this those wires may break off...

Nice congrats on the amp dude :tu: Welcome to the site too!! It's a good one!

I say post the pics so we have some form of reference here... I may not be much help but others will know I am sure of it.

Phatt you didn't even give him an Enzo "Probably Not"...

LoL I still can't even follow the question too much, but my knee jerk reaction huh?

I mean let's dissect the question... Preamp to Preamp to poweramp to guitar amp cab. <<< As long as it does not blow out speaker... 300 watt speaker 8 ohm rating is fine here.

But the real question is... "Would i get the same sound as i was using my Rocktron solid state guitar pa?" And I would have to answer that with an inexperienced "What?"

Yup got it working now! It was the bad insulation and it was just strange that each side(screwed down) would be fine until I started screwing in the the other side. So the insulation was failing when both sides were tightened down and that just had me confused. Thanks to all that contributed to this success...
Enzo, Roly & G1 you guys Rock!  :tu:

Take the chassis out of the enclosure and run it for at least ten minutes no speaker... Does the area of the chassis that is just below R37, R38 & R39 feel really hot? Try it for ten minutes with speaker connected and playing guitar. Does that same area feel really hot now?

I have the Roc Pro 700 which is a similar model but in combo amp form. I notice that area getting really hot on my amp once. I then sat there for a while trying to see if any chips were getting hot but it was not the output transistors connected to the heat sink getting hot. Instead I am pretty sure those wire wound resistors were generating a lot of heat. Test the voltage as 40vDC at R38 to ground and see what happens to the voltage after 10-20 minutes. Maybe something is heating up in this area. Very vague I know...sorry. That area of the amp gets really hot as I recall so that is where I would spend some time looking.

Sorry to spew out that silly line about "Harder to find..." Did not think enough on that one...  :duh

However, perhaps a G1M was used in the circuit as it looks in parallel to the diode clipping circuit? What do you think?

Quote from: Harley on January 30, 2013, 08:24:57 PM
Well it is a Princeton 65 DSP - The service diagram I have is 005741900 Rev D. 
As far as what's smoking - the solid state circuit board is discolored next to a 150 Ohm Dale resistor CP-5-3 10% 5W.

Please refer to part on the board such as R103 or R105 etc etc... Took longer to locate what part you are referring to here and I see it as R122. As far as where the smoke came from... That resistor generates heat, overtime the board will look a bit brownish. Probably not where the smoke came from... Look really careful for a fried component and even on the DSP daughter board too.

Quote from: Harley on January 30, 2013, 08:24:57 PM
It looks like someone replaced the instrument input jack at one time and the circuit board was broken where the effects switch is located.  I fixed this with super glue.  Could super glue on top of the copper circuitry cause an issue?

Damage to the board in the way Enzo described is a most likely culprit. If you have a DMM, test using the continuity setting and see if there is a short between traces/pads around the problem areas. Soldering small jumper wires between damaged trace points on the board can restore functionality. If the pads are torn off you have to get more creative and careful figuring out how to solder wire to the components. There are many techniques to use as you can rebuild traces too and not just using jumper wires.

Foremost, go check for continuity between all the traces that are known to be repaired items first and see what we find. Also, very curious where this smoke came from...?

It's a cheap lil Marshall practice amp and I remember replacing some broken pots on that amp. That was the 3rd amp that I bought to fix. Sure a Log is much better for Gain and Volume type controls but on this amp it really does not make all that much difference. I have all these pots still too... I went to Tayda for replacements... $1 pots free shipping! For this amp that is what is practical. I am sure they have the Log version of that pot, but if they are harder to find then that explains why it is linear.

So what parts got smoked?? Is this the Fender 65 DSP?? Yes it's worth fixing and it's worth selling for parts. What's it worth to you? Do you want to troubleshoot it??? Or just Shoot it?  :trouble

At least lets get specifics of what amp we are talking about and find a schematic to assess what components got smoked.  :crazy2: :blank:

So it looks like the preamp is working fine in various ways with exception of the T. Dynamics knob. So, there is something there that needs to be looked as far as connections within traces between that location of the PCB board. A schematic may prove to be helpful... Edit: Enzo is like a human Peavey schematic!! So I am sure he'll be the best to help with these amps in general.

Disconnect the speaker and take voltage reading on the terminals, any DC on the output? This will help to know whether there is something wrong on the output. I would do this just to make sure before doing anything else. That way we know that the output is relatively okay.

Frankly, I am not the one here to even give advice on this matter at all. In fact, looking at this schematic kinda scares the crap out of me as far as any modifying anything at all. I will attach this file here that I found on the MEF website as it could prove to be helpful for others that might be able to help you. Good luck

Yeah I ordered TO-3P silicon type insulators last night, so yeah mica would have been nightmare in this case. New insulators are probably needed here in this instance. This type of transistor does not require insulating washers on the screw so that is not a worry. Definitely will figure this out once new insulators arrive and will not proceed powering up unit till I figure this out. Thanks for the input guys!! :tu:

Yeah I will keep checking to see why *if* the insulation is failing, but it did not seem to be the connection. I will even pull out some mica insulators and just go that route in the end too. The power board has the four screw mounts connecting to the heat sink that have trace connections to the board. Still I am gonna have to figure it out before I feel comfortable plugging it in to the main voltage.