2002? DRRI Newly Acquired.. Look inside and tell me what I got myself into.. Pic Heavy

giogolf

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Since no one else has chimed in here with words of warning: I still think you should buy a cheap multimeter to make sure your filter caps are drained and scrape that spot. While you have the "doghouse" under the chassis where the caps live open, look for signs of leakage. Take it in for servicing ASAP if you see any. Otherwise, just plan to get it serviced some time relatively soon, or learn how to do it yourself.
I agree 100%. I have a multi meter and all the tools.. I am very handy, although never worked on tube amp other than, disassembly, deoxit and tube swaps..

I honestly would like to learn to do most of the work myself (need to practice soldering on something cheap first) and learn how to drain the voltage before poking around the board..

To sum up, Id rather learn myself now and scrape the carbon before I drop $150 on a tech to do a couple hours worth of work.
 

schmee

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Normally it's very hard to tell anything from photos, but when there's a burnt spot on the board, something is very wrong. Even if no components are damaged (yet!), you absolutely must scrape the black carbonized portion of the board clean. Carbon is conductive. View attachment 978807
Not entirely uncommon for those 470 ohm to burn up in those amps. They have likely been replaced and are fine now. The metal oxide resistors in there now look new. Why Fender didnt put them on the tube sockets I dont know, but probably too hard to assemble with former burger flippers.
I wold look at the Filter Caps and see if they have been replaced. If so, you are good to go.
Those amps are fairly easy to put a hand wired board into. But not for the non techy type I guess.
 

giogolf

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Not entirely uncommon for those 470 ohm to burn up in those amps. They have likely been replaced and are fine now. The metal oxide resistors in there now look new. Why Fender didnt put them on the tube sockets I dont know, but probably too hard to assemble with former burger flippers.
I wold look at the Filter Caps and see if they have been replaced. If so, you are good to go.
Those amps are fairly easy to put a hand wired board into. But not for the non techy type I guess.
Here are the caps..
whatcha think?
 

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Sea Devil

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Bad connections can cause hum. No big deal.
One of your caps has been replaced, so it's been serviced at least once in its lifetime.

The voltage drains automatically if you let the tubes heat up enough to produce sound and then turn off the power with the standby switch on. The meter is just to make sure. Just measure the DC from the + side of each cap to the chassis; you'll probably see a little residual voltage, somewhere between .5 and 9 volts, which is nothing to worry about.

I think if you scrape that carbon as a precautionary measure once you're sure the caps are drained, you'll be good to go for a while.
 

Sea Devil

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Hit those RCA connectors for the reverb with a little DeOxit, too -- preferably at both ends, which requires taking the pan out of the bag. That should prevent that hum next time you move things around.

It's not a bad idea to replace the other filter caps before they show any signs of trauma. I'd do it soon-ish, but it's not urgent. Practice your soldering skills first.
 
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zhyla

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Psionic Audio has a ton of good videos on this amp, showing innards and telling you what to look for.

That guy cracks me up. He’s very knowledgeable but some of his videos he’ll spend 20 minutes describing what’s wrong with the layout of an amp but then never show how it affects the sound or noise level.

I watched one where he spent a ton of time taking the knobs off and putting them back on just so. Very OCD.
 

schmee

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Here are the caps..
whatcha think?
That's a mix of colors! I suppose that means at least some were replaced... but not sure. Look for any bulging on the ends. I just used JJ 500V 20uf filters on the last one I did, not so expensive, but not the cheapies like those grey IC types either.
Maybe someone else here can remember if they were all the greys originally or not..?
 

Ten Over

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One of your caps has been replaced, so it's been serviced at least once in its lifetime.

The voltage drains automatically if you let the tubes heat up enough to produce sound and then turn off the power with the standby switch on.
Two of the caps have been replaced. The black one is new and the blue one is new.

No need for the tubes to be hot in order to drain the filter caps. Closing the standby switch (play mode) will drain the caps with or without the tubes.
 

KeithDavies 100

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Normally it's very hard to tell anything from photos, but when there's a burnt spot on the board, something is very wrong. Even if no components are damaged (yet!), you absolutely must scrape the black carbonized portion of the board clean. Carbon is conductive. View attachment 978807
This is one of the reasons I just LOVE this forum. 15 minutes, from posting to a really valuable answer. Well done, Sea Devil! @giogolf I hope you get it all sorted fine.
 

giogolf

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Oh and here is the Reverb tank.. Not sure its original based on the way it Loosely fits in the bag and just the bag is screwed into the base of the cabinet
 

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kbold

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Normally it's very hard to tell anything from photos, but when there's a burnt spot on the board, something is very wrong. Even if no components are damaged (yet!), you absolutely must scrape the black carbonized portion of the board clean. Carbon is conductive. View attachment 978807
The carbonising comes from a burnt out R62: R62 and R63 have been replaced, and as a precaution they have been raised from the PCB.
Since the PCB is single sided, and the burnt area is localised (seems not to be shorting to anything). IMO you could leave it as is.
 

Sea Devil

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A Gibbs tank! Score! That's even rarer than a US-made Accutronics. Ten Over is absolutely right, the old US tanks often sound better. Usually, IME.

Every source I've ever read says that turning off the standby absolutely will not drain the filter caps, though. Turning off the power will, and unplugging it with both switches on may too. Our own Rob Robinette describes the process here: https://robrobinette.com/Tube_Amp_Safety.htm

And kbold, I defer to you on the need to scrape the carbon. It did get the ol' Spider-sense a-tingling, though!
 
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kbold

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It did get the ol' Spider-sense a-tingling, though!
Burnt PCB's always attract attention ..... well, they should.
My assumption is that whoever replaced the resistors found the 'track side' of the board (which we can't see) to be OK.
Top side of the board? .... nothing to see here .... move along, move along.
 

giogolf

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Burnt PCB's always attract attention ..... well, they should.
My assumption is that whoever replaced the resistors found the 'track side' of the board (which we can't see) to be OK.
Top side of the board? .... nothing to see here .... move along, move along.
Since I have it apart again.. Ill make sure voltage is drained with my MM and then unscrew the board to peak at the other-side to make sure..

I know this is the honey moon phase, but jeez this thing just sounds glorious.. I have spent hours plugged straight in (no pedal board) just playing A pento accross all my guitars basking in the droning reverb.. Clean heaven…
 




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