Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Cups on May 04, 2011, 12:18:44 pm
-
You always hear about these stories but you never think it will happen to you. Anyways I found a Fender "the twin" in the electronic recycling bin. The chassis was seperate from the cabinet and there were no tubes but still an incredible find.
There is a huge scorch mark that almost burnt through the PCB where the current sense resistor is. Basically that resistor arched or opened.
I'll replace both resistors and it looks like an output grid resistor got some heat too.
I'm afraid the ouput tranny could be caput. I'll keep posted. If you have any insights or anecdotes that would be appreciated.
Patrick
-
There is a huge scorch mark that almost burnt through the PCB where the current sense resistor is. Basically that resistor arched or opened.
Patrick
Nice score Patrick!
That scorch mark is all the more reason to scrap the PCB and buy a Hoffman board.
3/4 of the cost of scratch building an amp are Tranny's, Cab, Chassis, Speaker (if a combo)
Even if the OT is shot (easy to test) you can build an AWESOME vintage amp into what you have for less than $200
Kudo's to you on your find
Ray
-
good mod amp
I never find anything like that. . .
back when I was in high school some one gave me a Plush amp. big black tuck and roll thing like the kustoms. but all tube. I made it work, after it shocked the crap out of me like five times before I figured out those big blue things stored electricity... Imagine that. One time I actually bridged the power switch with my pinky finger. It looked like a snakebite. And my room smelled like burning human. My dad asked if I was smokin pot in there. :laugh:
-
Excellent find there Cups!!
-
Schweet! Nice mod platform. Every Fender "The Twin" I ever heard belonged in a dumpster but all the more reason to build a really nice amp inside it. When you get it finished it'll be like having a 440 in an AMC Rambler. A lady I worked with years ago tried to give me a Dynaco ST-70 stereo tube amp and matching tube preamp after her husband passed away. I made her take $15 (all I had in my pocket) just to ease my conscience.
It's fun to be in the right place at the right time. Enjoy!
-
Thanks guys.
I'm trying to get it up and running and then decide what I want to do with it.
The low/high power switch was all undone and I'd like to find an image of the proper placing of the wires. Google images isn't really panning out. Would anybody have the wiring for that?
I'll try deciphering the schem again.
-
Fixed everything I could see but the amp will not light up at all. Power trans is pooched. Not worth fixing in my eyes.
I'll put it aside and I'm thinking of building two small amps inside. We'll see.