| Author | Message | ||
| Brian M. Watson (mrroundel) Username: mrroundel Registered: 06-2007 |
Well, I took a risk in replacing the reverb tank with the increasingly scarce Accutronics USA-made reverb tank. Still I have no reverb. Is there a relatively common failure in the reverb circuit on these amps that might be worth checking into? It's a 210 HD130 that appears to be all original, excepting new tank. It has the 12AX7 phase inverter. Any help is greatly appreciated. My next step is a reverb pedal, which I avoided because I don't want it on the floor of my presently cramped quarters. Thanks. | ||
| Mike Kaus (mm210) Username: mm210 Registered: 05-2006 |
Did you replace the tank BECAUSE it didn't work or was it an experiment? If it didn't work before the tank, then I'd probably look at the lm307 reverb drivers first. I ASSUME that you have the footswitch turned on, if you have one? Not trying to insult but I HAVE to ask. Also, I'd look at the cables going from the tank to the chassis and check them for continuity. THEn I'd dig into the drivers. Mike. | ||
| Brian M. Watson (mrroundel) Username: mrroundel Registered: 06-2007 |
Thanks Mike. Sorry for my delayed response. Yes, the footswitch was "on". I went to the tank purely in the hopes that it, being semi-mechanical, would be most prone to failure. After the tank replacement failing to fix the reverb, I've been messing around with different reverb pedals (Boss RV5 and T-Rex Roommate). I saw a post (perhaps yours) regarding what look like transistors (IC's?), of which there are two for the reverb and two for the tremolo. There's a company in the U.K. that has those components on Ebay. Tremolo works fine. I wish I would have read your post earlier today, before I put the old tank back in the amp. It would have been easiest to check the continuity of the tank cable with the tank out. Doh! Also, I just purchased a Marshall Bluesbreaker Reissue (no reverb), and was thinking about selling the MM. However, for some reason my singing voice likes the MM tone a bit better. It's weird, I know. I don't have to sell the MM, so I may hold on to it, as it's a sweet amplifier. Do you know anyone in the Southern California area who is well-versed in MM amp service? I'm in the L.A. area. I have no idea whether or not the cap's have been replaced, so I might just have someone replace the capacitors while fixing the reverb. Thanks for your help. Brian W. | ||
| a smith (a_smith) Username: a_smith Registered: 05-2006 |
Not in So Cal. You might check with Terry Loose. musicmanamp@yahoo.com He is a forum member. You will have to ship the chassis to him. | ||
| Brian M. Watson (mrroundel) Username: mrroundel Registered: 06-2007 |
Well, I actually removed the chassis from the cabinet and carefully checked for voltage at the various capacitors. There was zip. I'd done the unplugging while on trick, and then it's been about 10 days since it was plugged in. Anyway, once I removed the chassis and looked inside, I saw that it showed virtually no signs of any amateur repairs being done, if any were done at all. It was all impressively put together. 5 of the visible capacitors were Sprague brand, 4 blue ones rated at 150mf and 50V(500?), and one orange one that was on the fiber board closest to the output tubes. Are these original to the amp, or have they been replaced? I had wanted to identify the components that others here had described as sending their reverb "south". However, those old circuit boards aren't marked with component numbers so it wasn't going to be as easy as I thought. I decide that, considering the very pristine innards that my MM has, I didn't want to be the one to monkey it up. So, I'll wait until I take it to an able tech. There was a guy around here named Marty Pincus, but I believe he left the area. While I'm at it, can anyone identify the Spragues as being 1, original, and 2, Filter caps, or? http://home.earthlink.net/~bmw4re3/Music manGuts.JPG |
Tue, 03/25/2014 - 09:33
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