Ok- I discharged caps per instructional video that said hook one end of wire to chassis and the other to pin 1 of a tube socket. I guess it worked- I didn't touch the caps to find out.

Then I tested the diodes with my multimeter- it indeed has a diode testing feature. The ones at the front (top in the pic) all tested roughly between 7k and 10k. I tested the ones at the back and they all tested very close to each other at around 5 M. I guess this means they are OK?

I'll need to stop at the store and pick up a 40 watt bulb- I have plenty of 60 watters laying around if one of those might work.

Yes- turned it on without the power tubes in and still shorts out somewhere.

Ok- I built a limiter lamp and plugged the Peaver into it. I have a 15 watt bulb in it right now. Don't have a 20 to 40 handy- figured a 15 would be ok for now.

When I turn on the amp the bulb comes on probably its full brightness. The fuse does not blow. The amp doesn't look like it is coming to life though- no glowing tubes- no power light.

I've been letting it set for several minutes like this- not quite sure how to test the capacitors or where the rectifier diodes are. Doesn't look like any of the capacitors in the power section have been replaced. Several on the preamp board have been replaced however.

10-15 minutes passed and light still at full brightness and not life in amp. Turned off, turned on a few times... nothing.

This was working great not long ago. I had it serviced and several caps replaced but recently, I turned it on and there was a loud hum for about a second before the fuse blew. Replaced the fuse twice with the same results. Any thoughts on what might be the culprit? Have multimeter. Thanks- Chews.

OK- This one is going back to the store. Got it from Guitar Center and they said the only thing wrong with it was the reverb. Turns out there is an annoying intermittent static which only is apparent when playing clean with the "bright" switch engaged. It also just tripped the on-board breaker after playing for only about 5 minutes at moderate volumes. Might be more trouble than it is worth to deal with it when I have the 30-day return option.

I could deal with no reverb but these other issues are not worth the time or headaches.

OK- got the parts and built the signal tester. Wired two leads from one end of a guitar cable. Positive lead has .1 mf 620 volt non-polarized cap with a probe on end. Negative lead has alligator clamp on end. Using smallish practice amp for sound. Ready to go!  :dbtu:

That makes sense and explains it. Thanks! 

I don't have a signal tracer yet but I used the ohm setting on my multimeter to test that small grey capacitor near where the reverb wires connect and it reads nothing. I tested all the other caps, small and large, and they all read something at least for a few seconds, but this one- zilch. Does this indicate a bad capacitor?

Spoke too soon- That solder point is not connected to nothing... it is connecting to the grey capacitor just to the right of the solder bead. On the other side of the board it is connected to the same flow. This looks like it goes to pin 1 of that chip.

Also, I assumed this was the positive lead from the tank yet that grey capacitor looks oriented to the negative end where the positive lead of the cable connects.

now I'm really confused. 

NOTE: this post is wrong! Just leaving it here for completeness.... Chews.  :cheesy:


Ok- I'm pretty sure it has something to do with the missing cap/resistor/whatever. Before scrounging a tracing device- which I should have anyway- I took a closer look at the location of the missing cap because something just told me that that had to be the problem... or at least A problem.

With the amp tipped on its side and a light shining on the semi-translucent board, I used a kabob skewer and located the place where the missing cap would connect if it existed. Looking at the other side, the shadow of the skewer points to the exact location of where one of the leads (positive I think) to the reverb tank is soldered to the back of the board. This spot does not link with anything else. It is isolated and would only connect to one end of the missing cap.

The other lead (negative I think) of the same RCA cable originally was not soldered to the board. I resoldered it to where it looked like it was previously sodered but perhaps it was never connected at all? Could this be a possibility? I had to form an extension to the board from the cable as it had either been cut or was never there in the first place... if that makes sense. I'm wondering if I should remove the "resoldered" lead now. The other lead (positive I think) of this cable is clearly connected to the location of missing cap and the other (negative) lead is connected to the other end of the missing cap... but that end also flows to lots of other things... including the negative solder point of the other RCA cable to the reverb tank? But it wasn't connected and maybe it didn't have to be because ground was supplied by the other RCA jack? I dunno... I'm confused about that but the missing cap has got to be at least a part of the problem if not THE problem.

Again, I don't understand why anyone would remove it and render the reverb useless but still audible. If you don't like reverb, just turn it off. 

The attached images point to both sides of the board at the same location.

Should I try bridging the solder points of the missing cap to test it? Will that damage it? I don't have a cap to put in its place and I'm not sure what to get anyway- looking at the schematic- I'm guessing the 470k is what is missing? Forgive my noobiness.

And yes, the return RCA connector pops like a guitar cable would but the other is dead silent.

Thanks-

Chews

Hey all. Got this Randall and it is AWESOME but the reverb doesn't work. When I turn up the reverb, through the speaker- I can hear the springs sloshing around in there when I hit the amp or jostle it but there is no actual reverb signal attached to the guitar signal. Nothing seems to be driving the springs but I can still hear them when they clank.

At first I thought it was a lose wire. One of the two leads from the same RCA cable was broken off (or possibly cut off on purpose) from where it was soldered to the circuit board and I resoldered it. I figured that had to be it. I just soldered it back to the place where it looked like it used to be connected but there was no difference. 

On further inspection- It looks like several capacitors have been replaced and *possibly* a small cap/resistor was removed altogether from the area on top of the board directly over where said reverb wire connects on the opposite side of the board. I'm wondering if this missing cap could be the culprit and if so- why would someone just remove it?

In the pictures of the circuit board- the missing cap is directly between and above the second and third knob. The underside just shows where the wires for the tank come out.

I also hooked up a different reverb tank just to rule out the tank being the problem and it is not. Does the same thing on another tank that I know works.

Any help with this would be appreciated.

Thank you-

Chews

So- what if a dude was to want to set his Randall Commander head on top of his Lab Series L5 212 combo and run the both through the L5's speakers and use like an ABY box to switch between the two or even blend them?

Neither of these amps are channel switching amps so they don't have clean or dirty tones at the press of a button. I'd like to try to use the Randall for dreamy cleans and the L5 for punchy distortion but run them both through the L5's speakers so I don't have to lug another cab around.

Is this possible and relatively easy to do?

Thankie.

Chews. :cheesy:

I replaced all those caps- and other than it being not the neatest job in the world, it seems to be working great! I'm running it right now with an iPod- been going for about 30 minutes and sounds good.

I'll re-case it in a few hours if it doesn't show any signs of problems.

Thanks again guys. You're the best!

Chews.

thanks Roly and Dr. Gonz.

Ordered the big caps suggested above and picked up the three smaller ones at a local electronics supply store.

Fixin' to do some fixin'!  :dbtu:

Thanks DrGonz.