Results 1 to 35 of 35

Thread: '65 Pro reverb transformer change question

  1. #1
    Member
    Join Date
    Oct 2010
    Posts
    41
    Thumbs Up/Down
    Received: 0/0
    Given: 0/0
    Rep Power
    0

    '65 Pro reverb transformer change question

    Hi folks. This is my first post. I have a '65 Pro reverb that is sitting in my garage in France. It had power issues in the states and I brought it here hoping to fix it (I stopped gigging with it because it would suddenly loose volume). I'd like to swap out the transformer for a multi voltage one (so that I can select the voltage for whererever I happen to be), or at least, put a 220V transformer in it so that I can play it here in France. I don't want to use a step-down transformer.

    I am good with a multimeter and soldering iron, and I have the schematic. What transformer do I need, where can I buy it, and what should I look out for when making the swap?

    Thanks!

    0 Not allowed! Not allowed!

  2. #2
    Member
    Join Date
    Oct 2010
    Posts
    41
    Thumbs Up/Down
    Received: 0/0
    Given: 0/0
    Rep Power
    0
    OK, no bites ;-)

    I do not know why the amp was losing power (volume would drop 10+db in the middle of a gig), and I would like any advice on what to look for. The amp had all resistors, caps and diodes replaced about 15 years ago (it was pretty much completely rebuilt) and probably has not had more than 200 hours of use since then. I am now in france, so I have two problems: 1) I'm using an external 300watt stepdown transformer to power it. is 300w enough? 2) It makes no sound now, although the tubes do seem to warm up.

    As I said before, I am good with a soldering iron, and multimeter. I can also follow directions. Where should I start??

    Thanks for any help.

    0 Not allowed! Not allowed!

  3. #3
    Supporting Member txstrat's Avatar
    Join Date
    Mar 2008
    Location
    Germany
    Posts
    1,262
    Thumbs Up/Down
    Received: 0/0
    Given: 0/0
    Rep Power
    14
    300w is enough for the amp. It needs roughly no more than 150w (va).
    Have you ever worked in an open amp running under high voltage? If not, you might leave the work to an experienced technician. Those voltages CAN EASILY KILL YOU.
    If you still want to check it on your own, start from the outside. Pull the power tubes and test the voltage readings in the tubes sockets. Pin 3 has to have around 440vdc. Pin 4 slightly less. If you don't know which pin is what: the little nose is in between pins 1 and 8 (for an octal power tube socket). Pin 1 is left of the nose. All other numbers follow counterclock wise.
    Check the voltage between pins 2 and 7 (heaters). Report back, when you have the readings.

    For the dropping in volume I wouldn't think it's a transformer fault in the first place.
    First you should try different (known good) preamp tubes. If you don't have new tubes you might interchange them with each other and see what happens.
    Also the filter caps could be too old (people say they last about 15 years and that's what they are).
    For more possibilities look here: Low Power or Loss of Volume

    0 Not allowed! Not allowed!

  4. #4
    Member
    Join Date
    Oct 2010
    Posts
    41
    Thumbs Up/Down
    Received: 0/0
    Given: 0/0
    Rep Power
    0
    Hi txstrat. It took me the winter to get this project going. I checked the voltage at pins 3 & 4: 449vdc and 447 respectively. The heaters have NO voltage although the preamp tubes are glowing slightly. What next? ;-)

    0 Not allowed! Not allowed!
    Last edited by modusmongo; 03-18-2011 at 01:29 PM.

  5. #5
    Old Timer
    Join Date
    Jun 2006
    Posts
    3,315
    Thumbs Up/Down
    Received: 1/0
    Given: 0/0
    Rep Power
    17
    Heaters are AC, they will show half the voltage if read from pin 2 or pin 7 to ground. Your preamps wouldn't be glowing without the heaters.

    Does it make sound?

    0 Not allowed! Not allowed!

  6. #6
    Member
    Join Date
    Oct 2010
    Posts
    41
    Thumbs Up/Down
    Received: 0/0
    Given: 0/0
    Rep Power
    0
    Quote Originally Posted by MWJB View Post
    Heaters are AC, they will show half the voltage if read from pin 2 or pin 7 to ground. Your preamps wouldn't be glowing without the heaters.

    Does it make sound?
    Hi. Thanks for chiming in! 2.9 vac on each side of the heaters (2 & 7). Interesting, since I plugged it in today (first time since last fall) the voltage at pins 3 & 4 has dropped to 420vdc from over 450. I swapped the 12ax7s and it does make some sound! very little, but sound. I don't have any 12aT7's. Can I put a 12ax7 in there?

    What should I look at next?

    0 Not allowed! Not allowed!

  7. #7
    Old Timer
    Join Date
    Jun 2006
    Posts
    3,315
    Thumbs Up/Down
    Received: 1/0
    Given: 0/0
    Rep Power
    17
    Check dc voltage at pin 5 of the 6L6s.

    Check plate current in mA.

    Check AC voltage at pins 4 & 6 of the rectifier. Check dc at pin 8.

    You can put a 12AX7 in any preamp slot in a BF/SF Fender...whether it's what sounds best in there is another matter.

    0 Not allowed! Not allowed!

  8. #8
    Member
    Join Date
    Oct 2010
    Posts
    41
    Thumbs Up/Down
    Received: 0/0
    Given: 0/0
    Rep Power
    0
    -45 vdc at pin 5 of the output tubes (they're marked "5881" is that the same thing as a 6L6?). 330 vac at both pins 4 & 6 of the rectifier tube; 427 vdc at pin 8.

    How do I measure the plate current?

    Thanks fopr your help!

    0 Not allowed! Not allowed!

  9. #9
    Old Timer
    Join Date
    Jun 2006
    Posts
    3,315
    Thumbs Up/Down
    Received: 1/0
    Given: 0/0
    Rep Power
    17
    "How do I measure the plate current?" Either with bias probes, or with 1ohm 2W resistors inserted between pin 8 of each tube socket & ground (measure dc millivolts at pin 8). When you get some probes or 1ohm resistors, set the plate current to 30-35mA per tube.

    Your bias is on the hot side (too little voltage, much current). Until you measure the plate current, turn the bias pot to give maximum negative voltage at pin 5...if this makes the amp sound thin & harsh, reduce the negative voltage slightly. I'd like to see -50v there at least (voltages at pins 3 & 4 will rise slightly).

    Nowadays there is no specific difference between a 5881 and a 6L6. Whatever difference there ever was does not really apply to your amp & the conditions that the tubes need to live in.

    0 Not allowed! Not allowed!

  10. #10
    Member
    Join Date
    Oct 2010
    Posts
    41
    Thumbs Up/Down
    Received: 0/0
    Given: 0/0
    Rep Power
    0
    Okay, I got the voltage up to -50vdc at pin 5. The voltage also went up a bit on pins 3 & 4 - around 435vdc. The amp is still very quiet. Even on 10, I can bearly hear it. I hear my fingers on the strings better than I hear the amp. As for the plate current, I need to read up on that. Can you suggest a good place to start learning? Thanks.

    0 Not allowed! Not allowed!

  11. #11
    Old Timer
    Join Date
    Jun 2006
    Posts
    3,315
    Thumbs Up/Down
    Received: 1/0
    Given: 0/0
    Rep Power
    17
    OK, plate current does not seem to be your primary problem. For now just establish a way to measure it & set it as described.

    Is the sound low in both channels? Do the Pro speakers sound OK with another amp, what does the pro sound like through another cab? Attach an AC RMS voltmeter accross the speaker terminals & play, reading will jump around, determine an average & report back. If you use the Normal channel, you just need to fit V1 & V6, work through all your 12A#7 tubes & see if the situation remains the same.

    Record dc voltages for 12A#7 tubes (V1 to V6) pins 3, 8, 1 & 6.

    Amp unplugged from the wall, measure DC resistance from each power tube pin 3 to the red wire that meets the circuit board (comes through the chassis) at bottom left corner.

    Provide a hoto of yuor PT wiring (though you have heaters, necative bias & B+ voltages, all in reasonable proportions, so at a cursory glance all looks OK here).

    0 Not allowed! Not allowed!

  12. #12
    Member
    Join Date
    Oct 2010
    Posts
    41
    Thumbs Up/Down
    Received: 0/0
    Given: 0/0
    Rep Power
    0
    I don't remember ever having sound in channel 2. Something about a mod, but that's 20 years ago. The amp no longer has its cabinet. I've tried two different speaker cabs with the same result. Right now, it doesn't make any noise at all.

    I've swapped out every tube except the rectifier with no change. The only thing I can report is that the 12ax7 next to the output 5881 makes noise when I jiggle it, the rest are silent; and that when I accidentally touched two pins at the same time, the amp made a good old fashioned "plugging in the guitar" sound - LOUD! The volume pot was making some noise in the speaker, but now I'm hearing nothing.

    Voltage report: DC voltages pins 3, 8, 1, & 6 preamp tubes 1 - 6 (assumeing 1 is closest to the output tubes)

    tube 1 - 69, 69, 324, 214
    tube 2 - 0, 0, 422, 367
    tube 3 - 0, 0, 0, 0
    tube 4 - 7, 7, 422, 422
    tube 5 - 0, 0, 0, 0
    tube 6 - 0, 0, 0, 0

    Here are some pics from left to right from the rear. Please tell me which red wire to make the resistance tests with pin 3 of the 5881's




    0 Not allowed! Not allowed!

  13. #13
    Old Timer
    Join Date
    Jun 2006
    Posts
    3,315
    Thumbs Up/Down
    Received: 1/0
    Given: 0/0
    Rep Power
    17
    I thought you said you had a new power transformer?

    What's the pot coming off the reverb channel?

    I'd guess that the 4.7K 1W resistor in the cap pan, between the PI & preamp caps is open, replace this and the 1K 1W with 3W metal oxides.

    V1 is nearest the Normal channel inputs, V6 is next to the power tubes, you follow the signal.

    0 Not allowed! Not allowed!

  14. #14
    Member
    Join Date
    Oct 2010
    Posts
    41
    Thumbs Up/Down
    Received: 0/0
    Given: 0/0
    Rep Power
    0
    Quote Originally Posted by MWJB View Post
    I thought you said you had a new power transformer?
    Nope, I started this thread because I was thinking that I should replace the transformer because of power problems AND the fact that I live in France where the voltage is different. Thanks to txstrat, I am going to continue using the power inverter that I have, and find out what the real problem is with this amp.

    Quote Originally Posted by MWJB View Post
    What's the pot coming off the reverb channel?
    That is a "dwell" mod for the reverb. Quite nice.

    Quote Originally Posted by MWJB View Post
    I'd guess that the 4.7K 1W resistor in the cap pan, between the PI & preamp caps is open, replace this and the 1K 1W with 3W metal oxides.
    LOL. You're talking to a musician, not a technician ;-) What do these two items look like (a google image search has left my ignorance untarnished)? I see several doohickies on the "circuit board" to the left (from the back) which say ".047". Two are blue, and one is black, they're big cylyndrical jobbers.

    0 Not allowed! Not allowed!

  15. #15
    Old Timer
    Join Date
    Jun 2006
    Posts
    3,315
    Thumbs Up/Down
    Received: 1/0
    Given: 0/0
    Rep Power
    17
    Unplug from the wall, remove the chassis. Turn the chassis over so that you can see the transformers, PT to the left, choke to it's right, then the OT halfway down the chassis, next you have a square tin held down by 4 screws. Before you remove the screws, flick the standby into "play" mode to drain your caps. When you remove the cap pan lid you will see 5 big caps. At the bottom of the far right cap there is a yel/violet/red resistor bridging the cap to it's neighbour on the left, then from that cap to it's neighbour is a brown/blk/red resistor. These are the ones you want to change. If the caps themselves haven't been changed in the last 20 yrs, then these could benefit from being replaced too.

    0 Not allowed! Not allowed!

  16. #16
    Member
    Join Date
    Oct 2010
    Posts
    41
    Thumbs Up/Down
    Received: 0/0
    Given: 0/0
    Rep Power
    0
    HMMMMM. I opened the cap pan lid. I see the 5 caps. BUT, the resistors are in reverse order from what you describe. See photo. I removed them and tested them. They have the right resistance values. But the 1k was between the first and second blue cap, then the 4.7k between the second and third. I'll look for 3W replacements, but please let me know what you think about this reversed arrangement of the resistors (and the fact that they test ok at the proper values on my multimeter).

    Thanks again :-)


    0 Not allowed! Not allowed!

  17. #17
    Old Timer
    Join Date
    Jun 2006
    Posts
    3,315
    Thumbs Up/Down
    Received: 1/0
    Given: 0/0
    Rep Power
    17
    Well, if they are the wrong way round, your phase inverter will run at lower than normal voltage and your preamp tubes will run at higher than normal voltage...I doubt anything will blow, but it won't sound right. Where does the brown wire from the 4.7K go? Can you give us a shot of the whole cap pan? Those resistors look like 1W carbon film, I'd use 3W rated metal oxides.

    Do you get dc voltage at the + end of the 2 rightmost caps?

    0 Not allowed! Not allowed!

  18. #18
    Member
    Join Date
    Oct 2010
    Posts
    41
    Thumbs Up/Down
    Received: 0/0
    Given: 0/0
    Rep Power
    0
    Okay. I replaced the resistors in the correct order. Voltage is still relatively the same at all previously tested pins. The positive ends of the two rightmost caps in the cap pan read 436vdc. The brown wire goes to the center of the photo below (left side of the circuit board). Cap pan photo also provided. Question: the left most cap is inverted, that is it is negative end below and positive end above. All the other caps are positive end below.



    0 Not allowed! Not allowed!

  19. #19
    Senior Member
    Join Date
    May 2010
    Location
    Oakland, CA. USA
    Posts
    283
    Thumbs Up/Down
    Received: 0/0
    Given: 0/0
    Rep Power
    10
    modusmongo, where in France are you? I'm in Paris for a couple of weeks... PM me if you're nearby! If you're still having trouble maybe I could help!

    0 Not allowed! Not allowed!
    Don't believe everything you think. Beware of Rottweiler. Search engines are free.

  20. #20
    Member
    Join Date
    Oct 2010
    Posts
    41
    Thumbs Up/Down
    Received: 0/0
    Given: 0/0
    Rep Power
    0
    Hey Riz, What brings you to the land of baguettes and frogs legs? Are you on vacation? I live about 4 hours to the south-east of Paris, so we won't likely hook up, but if you make it down to Dijon, let me know and we'll have a (semi) cold one! Peter

    0 Not allowed! Not allowed!

  21. #21
    Senior Member
    Join Date
    May 2010
    Location
    Oakland, CA. USA
    Posts
    283
    Thumbs Up/Down
    Received: 0/0
    Given: 0/0
    Rep Power
    10
    A French girl, what else?! Actually there's plenty else, I love this place! I do miss being near my shop and tinkering, however, too bad you are a ways away. There may be a road-trip to Lyon, I'll let you know if we can stop along the way! Good luck with the amp, it will rock when you get it sorted out. Just take your time with the things you don't understand yet. Old Fenders are a great place to start learning this stuff--my first major "victory" was bringing back a Super Reverb that wouldn't make any sound, then an old Supro, and then, and then...!! You maybe should increase the wattage on those power resistors, as was recommended, I usually use 2-watt flame-proof. They are easy to get and cheap at my local electronics store. Good luck!

    0 Not allowed! Not allowed!
    Don't believe everything you think. Beware of Rottweiler. Search engines are free.

  22. #22
    Member
    Join Date
    Oct 2010
    Posts
    41
    Thumbs Up/Down
    Received: 0/0
    Given: 0/0
    Rep Power
    0
    Good luck with the frenchie ;-)

    This amp was my work horse in the '90s after I found it in a pawn shop in RI for $400 in a 4 x 10 cab. I put it in a 2 x 12 which I stole from a '68 twin (JBL 120's?), and the combination was immediately spectacular. The sound is so sweet and warm, and unlike the twin, I could play it at bar gigs set on 4 or 5, so it had some grit when I wanted it.

    I just finished shielding, rewiring and modding my '73 strat (parallel/series pull pot), and I want that max Fender sound!

    Thanks for the advice about the power resistors. I'm going to get the amp working again, then I'll open another thread to get as much advice as I can on what to replace and what to leave inside.

    I'll come see you if you're in the area. Enjoy your stay!

    Peter

    0 Not allowed! Not allowed!

  23. #23
    Old Timer
    Join Date
    Jun 2006
    Posts
    3,315
    Thumbs Up/Down
    Received: 1/0
    Given: 0/0
    Rep Power
    17
    Modusmongo, the 80uf cap at the far left is the right way around. The first 2 filter caps are in series, thus must be arranged with the "-" of the first cap connected to the "+" of the second cap. The cap second from left is getting the B+ voltage on its "+", the left hand cap has its "-" to ground, which is correct.

    So you have B+ voltage at all blue filter cap "+", this means that either you have a break in the B+ supply between the farthest right cap & the preamp tubes that it supplies, we know this because the farthest right cap shows no voltage drop from its neighbour, therefore no current is being drawn across the 4.7K resistor. Alternatively ALL the 12A#7 preamp tube plates fed by the righthand cap could have open resistors, or open cathode resistors...but this would seem very unlikely indeed.

    0 Not allowed! Not allowed!

  24. #24
    Senior Member
    Join Date
    May 2010
    Location
    Oakland, CA. USA
    Posts
    283
    Thumbs Up/Down
    Received: 0/0
    Given: 0/0
    Rep Power
    10
    Yeah a twin is just too freakin' loud! Are you getting proper voltage from your stepdown trannie? I recently got a 1:1 isolation trans for bench work, and it puts out a bit higher voltage than it gets on the primary, so I run it with a variac. Just a few volts higher, but if it gets 117v it puts out like 124... I think a replacement PT eventually would be a good idea if you want to gig it over here. I've toyed with the idea of moving here myself and have pondered what I'd do in your situation... Get it working first, and then look into swapping parts as you mentioned. Those film resistors are good and hold spec well, but some folks will advise carbon comps in some places for "tone". Here's an idea: if you have a program like Protools or Audacity (which is a free download), use it as a signal generator. Make a little thingie like the "listening amplifier" in this link: Amp Tools
    I'm assuming you don't have a scope, so maybe this will help you trace the signal from the input and see where you're losing it. I've never tried this myself, as I have a scope. But it might work for you. I have found a scope/signal injector to be the best tool ever for sussing out these kinds of problems, and without some kind of aid you are just shooting in the dark. I use Audacity myself at this point, it works fine for basic troubleshooting, but I'll get a "real" signal generator someday. MAKE SURE TO DRIVE THE AMP INTO A PROPERLY SIZED LOAD RESISTOR when using the signal injector, you don't want to create more problems. I get 25w 8-ohm resistors cheap at my local store and series/parallel them however I need to make the proper resistance with enough power handling. It's good to at least double the power handling capability of the load resistor to the output of your amp. In your case, 100w should do for testing purposes.
    You posted some voltages earlier, I need to go back and have a look at them. At a quick glance I noticed a lot of zeros in the preamp... Maybe some of the mods have gone wrong. When did it stop working, what happened?

    0 Not allowed! Not allowed!
    Don't believe everything you think. Beware of Rottweiler. Search engines are free.

  25. #25
    Supporting Member Jazz P Bass's Avatar
    Join Date
    Dec 2008
    Location
    Wernersville, PA
    Posts
    13,067
    Thumbs Up/Down
    Received: 606/3
    Given: 312/0
    Rep Power
    28
    Quote:"
    Voltage report: DC voltages pins 3, 8, 1, & 6 preamp tubes 1 - 6 (assumeing 1 is closest to the output tubes)

    tube 1 - 69, 69, 324, 214
    tube 2 - 0, 0, 422, 367
    tube 3 - 0, 0, 0, 0
    tube 4 - 7, 7, 422, 422
    tube 5 - 0, 0, 0, 0
    tube 6 - 0, 0, 0, 0"
    No wonder the amp does not work.
    These preamp voltages are not looking good.
    First : post the voltages as Pin #1 & 3/ Pin #6 & 8.
    Tubes 3, 5 & 6 have no plate voltage.
    You must check out why.

    0 Not allowed! Not allowed!

  26. #26
    Member
    Join Date
    Oct 2010
    Posts
    41
    Thumbs Up/Down
    Received: 0/0
    Given: 0/0
    Rep Power
    0
    Quote Originally Posted by riz View Post
    At a quick glance I noticed a lot of zeros in the preamp... Maybe some of the mods have gone wrong. When did it stop working, what happened?
    hi again. There are only two mods that I know of on this amp. One in the input and another for the reverb dwell. They are both very simple.

    The amp started to lose volume during gigs and I stopped using it because I had another setup I was interested in trying. For 15 years it has sat unused, and now there is no sound at all. But it's funny, once in a while, it will put out a VERY feeble sound (like 1/100th of a watt I imagine), then an hour later, I'll fire it up to do more tests, and there's nothing.

    I'm sure that it's something very simple, but as you say, I'm "shooting in the dark". The listening amp is a brilliant idea! Since I have no output at all, couldn't I just plug the amp into a cabinet for a load? If I understand the idea, I could start at the input and follow the signal until it breaks. Cool!

    Thanks ;-)

    0 Not allowed! Not allowed!

  27. #27
    Old Timer
    Join Date
    Jun 2006
    Posts
    3,315
    Thumbs Up/Down
    Received: 1/0
    Given: 0/0
    Rep Power
    17
    You know what is wrong, your preamps are drawing no current/have no voltage. Do a continuity test from the farthest right cap in the pan (preamp cap) to the junction of the 100K plate resistors at pins 1 & 6 of the preamp tubes. If there is no continuity, the wire feeding these points is broken. What do you get?

    0 Not allowed! Not allowed!

  28. #28
    Member
    Join Date
    Oct 2010
    Posts
    41
    Thumbs Up/Down
    Received: 0/0
    Given: 0/0
    Rep Power
    0
    Thanks MWJB. I'll do this tomorrow after my boy goes to his mom's house ;-)

    Thank you everyone for your help!

    0 Not allowed! Not allowed!

  29. #29
    Member
    Join Date
    Oct 2010
    Posts
    41
    Thumbs Up/Down
    Received: 0/0
    Given: 0/0
    Rep Power
    0
    FIXED!! Thank you SO much. I followed the yellow wire back to the circuit board, and it was detached. First one! I'm very happy. The amp makes a bit of noise, but I have the soldering iron right next to it, and it is open. I'll be posting another thread concerning the replacement of old components and asking advice on "tone" decisions. I also need to learn how to bias it. Anyone want to suggest a link?

    MWJB, you are my hero!

    0 Not allowed! Not allowed!

  30. #30
    Old Timer
    Join Date
    Jun 2006
    Posts
    3,315
    Thumbs Up/Down
    Received: 1/0
    Given: 0/0
    Rep Power
    17
    Add a 1ohm 2W resistor between each 6L6 socket pin 8 and it's ground connection (use the chassis ground that is already there, don't try & resolder them unless you are a total massochist) make sure the 1ohms are matched - "zero" your meter by putting the leads together, if it reads 0.3ohms with the leads together (no resistance) use resistors that read 1.3ohms. Read your plate current at pin 8 of each power tube in millivolts, this converts to to milliamps thanks to Ohm's law. Set to 30-35mA/mV.

    Or, buy some bias probes like the TAD biasmaster, this will save you having to drop the chassis every time you install/bias up new tubes.

    "MWJB, you are my hero!" I only worked out what was wrong because you told me, you found & fixed the break...we'll go 50/50 on the heroics if you like ;-)

    0 Not allowed! Not allowed!

  31. #31
    Member
    Join Date
    Oct 2010
    Posts
    41
    Thumbs Up/Down
    Received: 0/0
    Given: 0/0
    Rep Power
    0
    I'm not finding 3W resistors where I shop. Can I use 5W metal oxide for the resistors between the preamp caps?

    0 Not allowed! Not allowed!

  32. #32
    Member
    Join Date
    Oct 2010
    Posts
    41
    Thumbs Up/Down
    Received: 0/0
    Given: 0/0
    Rep Power
    0
    Quote Originally Posted by riz View Post
    Those film resistors are good and hold spec well, but some folks will advise carbon comps in some places for "tone".
    Hey Riz. Can you elaborate please? I'm making a big shopping list for the online electronics store and I'd like to know exactly which resistors to replace, and with what.

    As for the resistors, I see some 5W metal oxides. Would they be good for between the preamp caps? I can't find any 3W (suggested by MWJB). You mentioned 2W "fire proof"; I do see some 2W metal oxide "Excellent flame retardant coating".

    Thanks ;-)

    0 Not allowed! Not allowed!

  33. #33
    Old Timer
    Join Date
    Jun 2006
    Posts
    3,315
    Thumbs Up/Down
    Received: 1/0
    Given: 0/0
    Rep Power
    17
    Yes, 2W would work too.

    0 Not allowed! Not allowed!

  34. #34
    Senior Member
    Join Date
    May 2010
    Location
    Oakland, CA. USA
    Posts
    283
    Thumbs Up/Down
    Received: 0/0
    Given: 0/0
    Rep Power
    10
    Well I could try, but this fella's already on top of it!
    http://www.geofex.com/article_folder...carboncomp.htm

    0 Not allowed! Not allowed!
    Don't believe everything you think. Beware of Rottweiler. Search engines are free.

  35. #35
    Member
    Join Date
    Oct 2010
    Posts
    41
    Thumbs Up/Down
    Received: 0/0
    Given: 0/0
    Rep Power
    0
    great article!

    0 Not allowed! Not allowed!

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Fender 65 Deluxe Reverb Reissue Power Transformer?
    By Tonestack in forum Guitar Amps
    Replies: 4
    Last Post: 07-10-2010, 01:43 PM
  2. Question about Pro Reverb OT impedance
    By Regis in forum Maintenance, Troubleshooting & Repair
    Replies: 17
    Last Post: 05-26-2010, 05:32 PM
  3. Fender Pro Tube Pro Reverb - Dead Tremolo and Noisy Reverb
    By pmwalk in forum Maintenance, Troubleshooting & Repair
    Replies: 1
    Last Post: 12-09-2009, 10:54 PM
  4. QUESTION: Biasing a '65 Reissue Deluxe Reverb
    By Mango Moon in forum Maintenance, Troubleshooting & Repair
    Replies: 4
    Last Post: 10-09-2008, 02:30 AM
  5. Sovtek mig 50 - Transformer change.
    By Poffa in forum Maintenance, Troubleshooting & Repair
    Replies: 6
    Last Post: 08-06-2008, 03:25 AM

Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •