Ben
Joined: Feb 11, 2007
Posts: 591
Encinitas, Ca
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Posted on Nov 22 2008 11:00 AM
I'm hoping some of the amp guru's are around this morning.
I have a 1966 Tremolux head/cab. The tremolo has not worked since I've had the amp but otherwise, it sounds killer. I have swapped out the tubes and the foot switch is fine on other amps.
How do I trouble shoot this issue? Is it just a case of replacing the roach? Anyway to test it? Any other components that need to be checked or replaced? I'm good at soldering, I have the schematics and a DVM.
Also, assuming I will be ordering parts, is there a way to slow down the tremolo effect by changing values of specific components? I have had this done on other amps.
While you guys are thinking about that, I'll be clearing off the workbench.
Any advice is appreciated.....Thanks
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Kman1
Joined: Aug 29, 2008
Posts: 694
Surf City
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Posted on Nov 22 2008 11:50 AM
Might be a transistor issue.
—
Sonichris
I also like to think that all early 60's fender equipment is happy to be playing surf music again. After all, its the music it was meant to play.
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DannySnyder
Joined: Mar 02, 2006
Posts: 11077
Berkeley, CA
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Posted on Nov 22 2008 12:21 PM
Kman1
Might be a transistor issue.
Why would you think that Kman? 
— Danny Snyder
"With great reverb comes great responsibility" - Uncle Leo
I am now playing trumpet with Prince Buster tribute band 'Balzac'
Playing keys and guitar with Combo Tezeta
Formerly a guitarist in The TomorrowMen and Meshugga Beach Party
Latest surf project - Now That's What I Call SURF
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Ben
Joined: Feb 11, 2007
Posts: 591
Encinitas, Ca
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Posted on Nov 22 2008 12:34 PM
I've already replaced the transistors... 
Any other ideas?
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Ruhar
Joined: Jun 21, 2007
Posts: 3909
San Diego, CA
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Posted on Nov 22 2008 01:40 PM
Ben, I have the same issue with my Dual Showman. I'm assuming its just in need of a new roach. I just haven't taken the time to get it fixed. I'd be interested in what other people have to say also though...
— Ryan
The Secret Samurai Website
The Secret Samurai on Facebook
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Brian
Joined: Feb 25, 2006
Posts: 19345
Des Moines, Iowa, USA
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Posted on Nov 22 2008 01:42 PM
Kman1
Might be a transistor issue.
Might be a forum member removal issue. 
— Site dude - S3 Agent #202
Need help with the site? SG101 FAQ - Send me a private message - Email me
"It starts... when it begins" -- Ralf Kilauea
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diceophonic
Joined: May 20, 2006
Posts: 2174
PacNW (Vancouver, Wa U.S.A.)
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Posted on Nov 22 2008 02:06 PM
DannySnyder
Kman1
Might be a transistor issue.
Why would you think that Kman?
Here is what I think
Vibrato tube going bad, either the oscillator section or the driver section swap it and see.
Neon/LDR module going bad
Broken/open resistor, capacitor, or wiring
Faulty speed or intensity control
Faulty vibrato footswitch , jack, or wiring
Kyle
— -Kyle
Beyond The Surf YouTube channel
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The Verbtones @ bandcamp
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Kman1
Joined: Aug 29, 2008
Posts: 694
Surf City
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Posted on Nov 22 2008 02:08 PM
DannySnyder
Kman1
Might be a transistor issue.
Why would you think that Kman?
Whenever someone has had an issue with something dieing on their amp from overall power, to reverb, tremolo and other effects, it's often been a transistor issue. And, I thought that may help someone figure out what is wrong if I was wrong.
Ben
I've already replaced the transistors...
Any other ideas?
You live you learn, huh? ;)
Brian
Kman1
Might be a transistor issue.
Might be a forum member removal issue.
Was that neccesary? 
—
Sonichris
I also like to think that all early 60's fender equipment is happy to be playing surf music again. After all, its the music it was meant to play.
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D22
Joined: Apr 20, 2006
Posts: 2056
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Posted on Nov 22 2008 02:17 PM
Ben,
Here's the quick and painless approach. Swap out the normal channel tube (V1) for the tremolo tube (V3). If it doesn't work maybe the roach has died --all things considered working properly.
Gluck broham, Dman
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Last edited: Nov 22, 2008 14:20:40
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DannySnyder
Joined: Mar 02, 2006
Posts: 11077
Berkeley, CA
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Posted on Nov 22 2008 02:18 PM
Sigh.....Kman, here's a schematic of a tremolux, show me where the transistors are.
http://www.ampwares.com/amp.asp?id=109
— Danny Snyder
"With great reverb comes great responsibility" - Uncle Leo
I am now playing trumpet with Prince Buster tribute band 'Balzac'
Playing keys and guitar with Combo Tezeta
Formerly a guitarist in The TomorrowMen and Meshugga Beach Party
Latest surf project - Now That's What I Call SURF
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eddiekatcher
Joined: Mar 14, 2006
Posts: 2778
Atlanta, GA
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Posted on Nov 22 2008 03:03 PM
Dice-o is on the right track. You can check the neon bulb by removing the chassis and plugging the amp in somewhere dark. From the front you can usually sight down the circuit board to verify that the light is blinking on and off. It will not blink without the foot switch plugged in and engaged or the jack is shorted from tip to ground. These bulbs frequently burn out. That's why most of the Standell amps from the awful "colored module" era seldom have a working tremolo. Bob Crooks had the "foresight" to seal the blub and photo resistor in epoxy in the module........smart!
The other easy possibility is some evil Eddie Katcher type has removed one wire from the intensity pot to give the vibrato channel a little boost. The vibrato circuit drains signal even when it isn't operating and some guys (and I won't name any names) like to disable the circuit for more gain. Look for a loose wire.
good hunting
ed
— Traditional........speak softly and play through a big blonde amp. Did I mention that I still like big blonde amps?
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Brian
Joined: Feb 25, 2006
Posts: 19345
Des Moines, Iowa, USA
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Posted on Nov 22 2008 04:55 PM
Kman, there are no freaking transistors in that amp. Please don't reply to something unless you have something of value to add to the thread. 
— Site dude - S3 Agent #202
Need help with the site? SG101 FAQ - Send me a private message - Email me
"It starts... when it begins" -- Ralf Kilauea
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Ben
Joined: Feb 11, 2007
Posts: 591
Encinitas, Ca
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Posted on Nov 22 2008 05:07 PM
Here's an update guys:
Foot switch is good.
At best I am getting a very weak tremolo on max intensity, but almost imperceptible. I am also getting a little pulse/ticking. The speed and intensity pots do work to control what I do get.
Swapped tubes in the V3 spot.
I do see a flickering light from the roach
No sign of "Evil Eddie" mods. Wiring appears intact.
This amp appeared untouched inside when I got it. I looked at every solder joint and compared it to the schematics. I replaced the electrolytic caps on the circuit board and the filter caps. Other than swapping tubes for this experiment they are the ones that came with it. Phillips power tubes and no name pre-amps.
Can a roach go bad and still produce a weak effect?
Would bad tubes produce weak effect?
Or, are these things either good, or no good?
Thanks for the help guys.
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DannySnyder
Joined: Mar 02, 2006
Posts: 11077
Berkeley, CA
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Posted on Nov 22 2008 05:14 PM
Ben, Eddie posted this for my reverb issue but should apply to anyone's issues really:
eddiekatcher
Danny, here are a few of my trouble shooting methods:
Remember there's high voltage in that thar thingy, so be careful and keep your fingers out of there.
Then remove the back cover and one at a time, with the unit plugged into an amp with your normal settings on the amp and unit, lightly thump on each tube with the fingernails on your first two fingers. Flutter your two fingers rapidly back and forth. This is a good check for microphonic or erratic tubes.
Ok so far? Now get a small wooden dowel (NOT a wood pencil) and press around lightly, then moderately on each component and solder joint. You would not believe how many issues I've uncovered using a simple stick. I've found several connections that were never soldered at the Fender factory from the '60s. It will also help to uncover any broken wires or PC traces. These show up most often in the vintage amps in the best condition physically. Often times these amps probably had some intermittent issue that the owner gave up on trying to have fixed and sold the amp to someone else who, in turn went through the same deal passing it on and on.
I'll bet you uncover something doing this. Also swap out the tubes one at a time. A funky tube will do strange things.
Good hunting!
ed
— Danny Snyder
"With great reverb comes great responsibility" - Uncle Leo
I am now playing trumpet with Prince Buster tribute band 'Balzac'
Playing keys and guitar with Combo Tezeta
Formerly a guitarist in The TomorrowMen and Meshugga Beach Party
Latest surf project - Now That's What I Call SURF
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Brian
Joined: Feb 25, 2006
Posts: 19345
Des Moines, Iowa, USA
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Posted on Nov 22 2008 05:18 PM
Ben it could be the roach. I had mine replaced in my Showman and my tremolo got a lot better. I'm still not fully happy with it. The next step for me would be to try and get one of those surf bugs (a super duper roach):
http://www.tonecraftamprepair.com/html/surf_bug.html
— Site dude - S3 Agent #202
Need help with the site? SG101 FAQ - Send me a private message - Email me
"It starts... when it begins" -- Ralf Kilauea
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D22
Joined: Apr 20, 2006
Posts: 2056
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Posted on Nov 22 2008 05:30 PM
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eddiekatcher
Joined: Mar 14, 2006
Posts: 2778
Atlanta, GA
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Posted on Nov 22 2008 05:54 PM
Ok now let's boogie.................replace the two 25-25 caps on the 12ax7 for the tremolo. One or both may be leaking. Those caps and their 27k and 100k resistors are what "bias" the trem tube...............ed
— Traditional........speak softly and play through a big blonde amp. Did I mention that I still like big blonde amps?
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Icetech
Joined: Dec 16, 2006
Posts: 892
Macomb Mich
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Posted on Nov 22 2008 06:33 PM
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Kman1
Joined: Aug 29, 2008
Posts: 694
Surf City
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Posted on Nov 22 2008 07:01 PM
Sorry, haven't been able to post from my PSP. I only posted that because I thought it could help someone figure out what was wrong, though I thought I was right.
—
Sonichris
I also like to think that all early 60's fender equipment is happy to be playing surf music again. After all, its the music it was meant to play.
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Bill_Ashton
Joined: Nov 15, 2008
Posts: 124
Massachusetts
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Posted on Nov 22 2008 07:22 PM
I have a blackface/white tolex Tremolux head. This model (the date code escapes me) has the neon lamp/photo-resistor that operates the tremolo. I have always been able to actually see the lamp flickering through one of the inputs.
At one point I lost the tremolo; as it turns out, the tremolo foot switch jack, which should have a small RCA shorting plug in it when a footswitch is not used, actually went bad or got tarnished enough inside so that the tremolo would not work. As this style jack is kind of a oddball today, a shorting lead across the jack restored my tremolo...of course I cannot use a remote foot switch with it now.
Point of all this is 1) you need to have a shorting plug in the jack if a footswitch is not plugged in and 2) you should look to that jack to insure the tremolo is even getting turned on.
Good luck...trying to restore the tremolo on my '63 Guild 66-J has been nowhere near as easy!
— Of all the things I've lost, I miss my mind the most...
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