mustang guy Posted August 28, 2013 Share Posted August 28, 2013 (edited) Click here to go to current post... Edited December 20, 2013 by mustang guy Quote Link to comment Share on other sites More sharing options...
mustang guy Posted August 28, 2013 Author Share Posted August 28, 2013 (edited) I am happy to say everything worked out great.... Edited December 20, 2013 by mustang guy Quote Link to comment Share on other sites More sharing options...
Boxx Posted August 28, 2013 Share Posted August 28, 2013 OK, I am blind as a bat. Now that I have my cheaters on I can see the slot in the socket. Never mind.... Some may argue this, but I would advise the use of gloves when handling your tubes. Quote Link to comment Share on other sites More sharing options...
Dr Morbius Posted August 28, 2013 Share Posted August 28, 2013 Sooooooooooo, how does it sound, now that you've got your tubes in? Quote Link to comment Share on other sites More sharing options...
Dr Morbius Posted August 28, 2013 Share Posted August 28, 2013 Btw, are those EL37's your using or are they 6L6's? I believe your Fisher originally came with the EL37 but they are hard to find now and I think you can use the 6L6 but it's not as good sonically as the EL37's. Quote Link to comment Share on other sites More sharing options...
mustang guy Posted August 28, 2013 Author Share Posted August 28, 2013 It sounded great for the 10 minutes before I unplugged it. Heard a sizzle, saw some smoke, the thing kept playing perfectly, but I yanked the plug. When I get a chance, I will look underneath. Working on a car right now so the amp will have to wait. I will say this, the Fisher 80T mated to the 80AZ mated to a LaScala is wonderful. I had the max set at 1 watt and it still filled the shop with sound. Amazing... Quote Link to comment Share on other sites More sharing options...
mustang guy Posted August 28, 2013 Author Share Posted August 28, 2013 Btw, are those EL37's your using or are they 6L6's? I believe your Fisher originally came with the EL37 but they are hard to find now and I think you can use the 6L6 but it's not as good sonically as the EL37's. I am using Gold Lion KT66's. It was recommended by a guy who has restored many 80AZ's in a thread I was reading. I cannot say if they are good or bad. What I can say is they are good enough for me. I'm gonna crack the case open and take a picture to post. Quote Link to comment Share on other sites More sharing options...
mustang guy Posted August 28, 2013 Author Share Posted August 28, 2013 (edited) pic1 of 5 Edited November 28, 2013 by mustang guy Quote Link to comment Share on other sites More sharing options...
mustang guy Posted August 28, 2013 Author Share Posted August 28, 2013 (edited) pic 2 of 5 Edited November 28, 2013 by mustang guy Quote Link to comment Share on other sites More sharing options...
mustang guy Posted August 28, 2013 Author Share Posted August 28, 2013 (edited) pic 3 of 5... It looks like the resin or oil came from here. This is the bottom of one of the cap cans. See where it looks like it shot over the green thing? Edited November 28, 2013 by mustang guy Quote Link to comment Share on other sites More sharing options...
mustang guy Posted August 28, 2013 Author Share Posted August 28, 2013 (edited) pic 4 of 5 Edited November 28, 2013 by mustang guy Quote Link to comment Share on other sites More sharing options...
mustang guy Posted August 28, 2013 Author Share Posted August 28, 2013 (edited) final picture. Look at the brown crud.... It looks like resin. I have a spray can of contact cleaner. Should I try to clean that up? I wonder if that was was sizzling and smoking. On the other hand, why would it only start after 10 minutes of playing at 1 watt? Edited November 28, 2013 by mustang guy Quote Link to comment Share on other sites More sharing options...
mustang guy Posted August 28, 2013 Author Share Posted August 28, 2013 (edited) Here is the culprit (I think). It says C-592-14640 MFDWVDC 500 and a little half circle flat on bottom40 MFDWVDC 500 and a little triangle616817CAN NEG PAT.2.623.101 Edited November 28, 2013 by mustang guy Quote Link to comment Share on other sites More sharing options...
mustang guy Posted August 28, 2013 Author Share Posted August 28, 2013 Just finished researching this. It is a 2 section capacitor: 40uf/500v and 40uf/500v. I have a Blue ESR meter at home that I can check the rest of the caps with, but I'm pretty sure this one is a goner. I need to know where I can buy one of these, and if it's OK to spray contact cleaner under the chassis to get rid of all the ****. Any and all advice will be appreciated. Quote Link to comment Share on other sites More sharing options...
mark1101 Posted August 28, 2013 Share Posted August 28, 2013 Good Lord, that amp needs a rebuild. There is no way I would plug that thing in till a competent tech recaps it and rebuilds the power supply. That thing has the original ceracaps in it. Don't burn your house down. Quote Link to comment Share on other sites More sharing options...
tube fanatic Posted August 28, 2013 Share Posted August 28, 2013 Looking at your pix, the entire amp needs to be worked over by an experienced tech. The brown gooey stuff on the outside of some of the caps is normal- those have a wax type covering which melts from the under-chassis heat. However, all those caps need to be replaced as they are notorious for being extremely leaky (electrically speaking) and prone to failure with age. I see some ceramic caps which also must be replaced. Replacing only the electrolytic caps may make things worse as the B+ voltages will likely be much higher after replacement resulting in additonal stress on other parts which need replacement. All resistors need to be checked for out of tolerance values. Don't attempt to do this yourself unless you are very well versed in doing this type of work and dealing with potentially lethal voltages in a safe manner! There are so many possible failure points in an amp like this that trying to do the job only partially is absolutely not recommended unless you want to risk a catastrophic power or output transformer failure. Maynard Quote Link to comment Share on other sites More sharing options...
tigerwoodKhorns Posted August 28, 2013 Share Posted August 28, 2013 How old is the amp? Beware of really old caps that are leaking. Full of PCB's which Monsanto said were harmless way back when... Quote Link to comment Share on other sites More sharing options...
mike stehr Posted August 28, 2013 Share Posted August 28, 2013 Actually they are the wax covered Goodall caps, not a Ceracap like a Scott integrated amp or such would have. The old 'lytic PS capacitors are the ones of concern to me...with those wax Goodall caps as well. I'd go ahead check over all the resistors, as I'm sure a few of those carbon composition resistors have drifted out of tolerance. When I come across a old vintage tube amp or integrated amplifier, the first thing I'm concerned about is the PS transformer. Once that is checked and passes, I then check over the output transformers/transformer. Once those pass testing, one can continue on. No sense buying caps and resistors when you have a smoked PS xformer or a burnt OPT. I really doubt any iron has any problems with the old mono Fisher...but it never hurts to check. More than likely that PS cap which blew goo all over the multi-tapped resistor. If the thing caught on fire from some off chance, the guy was right there to power it down and throw it out in the front yard if need be... Quote Link to comment Share on other sites More sharing options...
beeker Posted August 28, 2013 Share Posted August 28, 2013 Seeing this thread i want to jump onboard to get some vacuum tube pointers as well. There are some good websites with tube info as well as good tech service. A lot of you guys have tons of tube experience so who would you suggest sending vacuum tube units to that are honest, good and reasonable pricing on repairs and or upgrades. Then where are the best notes on tube amps? From caps to biasing where is the best info. Boxx suggested wearing gloves and these are the pointers i appreciate. Thank you for help and direction. I hope your cool with me jumping in here mustang cause this has been weighing on me for a while now having several tube units in use and really only being a few years into tube use. Thank you for direction...unless im asking too much here Quote Link to comment Share on other sites More sharing options...
Dr Morbius Posted August 28, 2013 Share Posted August 28, 2013 The man to speak to about this would be Craig at "NOSValves" who is pretty knowledgeable about these things................. just don't bother him too much, as he's rebuilding a Scott amp for me now! Quote Link to comment Share on other sites More sharing options...
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