ampage
Tube Amps / Music Electronics
For current discussions, please visit Music Electronics Forum. New: view Recent Searches.
New: visit Schematic Hell!
The sunn still shines online!

 
Listen to great tunes streaming live right now!

ampage archive

Vintage threads from the first ten years

Search for:  Mode:  

Tweed Princeton Output Transformer


 
10/30/2005 11:04 AM
gtrgeo
email
Tweed Princeton Output Transformer
I own a tweed Princeton that had endured many years of abuse before I acquired it more than 20 years ago. I had to replace the output transformer shortly after I got it and the folks that I contacted at fender sent me a schematic with some part numbers listed on it and a local place to buy the parts. I was sold a 022913 transformer and told to use an 8 ohm speaker with it. Years later I notice that the schematic is for a 5F2 and looking at my amp I notice that it looks more like a 5F2-  
A with the absence of the choke and separate power switch.  
My question. Is this transformer ok for this circuit or should I replace it?  
 
Sorry for being so long winded,  
George
 
11/2/2005 4:07 PM
Chris/CMW amps
email

Hi George  
 
That transformer is for a blackface/silverface PrincetonReverb amp; 2x6V6 push-pull.... so not ok.....  
Afaik http://www.MercuryMagnetics.com does offer an outputransformer (exact replica) for your tweed Princeton, just contact Paul at MM.  
 
Hope this helps,  
 
Chris
 
11/2/2005 6:13 PM
gtrgeo
email

Chris,  
Thanks for the help. I will contact MercuryMagnetics and see what they have. I have run this transformer in the amp using half the winding. I was told by fender to use the whole winding and cap the center tap. I installed the OT over 2o years ago when I was a kid and I don't remember why but I didn't hook it up correctly. I had it connected to one end and the center tap. The amp works but has been disassembled for years in hopes of recovering the cabinet. Is there any chance that I have damaged other components in the amp running it this way?  
 
Thanks again,  
George
 
11/3/2005 12:21 AM
Chris/CMW amps
email

Hi George  
 
Can't tell you about that OT right now but in general witch such "old amp":  
- check all voltages  
- check all tubes  
- check all couplincaps if they don't leak (scratchy volume-control as example)  
- check all e-caps  
- clean the inputjacks and pots  
 
Be carefull with the high voltages inside. You do have a pretty $$$ amp so only replace parts if really needed, some guys will pay more for a more original one if you do wanna sell it.  
 
Chris
 
11/3/2005 1:16 AM
Chris/CMW amps
email

Hi George  
 
Here's a list from tweed princeton OTs from the MM website:  
 
ToneClone OT FTPO-5 '60 Tweed Princeton -- 4 ohm tap $40.00  
 
ToneClone OT FTPO-5M '60 Tweed Princeton -- 8 ohm tap $55.00  
 
ToneClone OT FTPO-55 '55 Tweed Princeton $50.00  
 
I guess (!) it should be one of the 1st two options. Check the impedance of the original speaker.  
 
Chris  
 
Ps I don't work at MM but they do make such great transformers! :)
 
11/3/2005 8:09 AM
gtrgeo
email

Thanks Chris so much for the help,  
I'm assuming that the date code is the number stamped after the model number on the tube chart. In my case, I believe it says "5F2 GF", which as far as I can tell would be a 1957. I am not sure what the original speaker was as a previous owner hacked a hole in the baffle board and stuck a 12 EV speaker in. That speaker is long gone. I want to replace the baffle board and speaker, but I am unsure what speaker to use. That will be the next step after figuring out which OT. As far as being worth much money. I'm not sure. At some point, somebody took off the tweed and recovered with creme covered tolex and it looks like the amp lived outside for a while. the chassis has rust both inside and out. The guy that I got it from thought he would fix it up and attempted to steel wool the rust on the face of the chassis, thus removing some of the lettering. And to top it off, he spray painted the tolex black. Some one also drilled an extra hole in the face of the chassis. So, I figure it will be more of a user amp than a show piece. I would like to re-cover it with tweed so that it looks proper.  
 
Thanks again,  
George
 
11/3/2005 8:50 AM
Chris/CMW amps
email

Hi George  
 
You're welcome and if you were living in the Netherlands I should invite you for a visit to my shop.  
Ok, it's not a mint condition tweed Princeton anymore...  
All parts will cost you money; if you do wanna have the tweed princeton sound then get a nice replica OT and replace the e-caps and tubes (just doing a cap-job on a '63 Showman with stock e-caps...).  
I'm not a fan of small speakers to be honest and I've build a couple of Champ/tweed Princeton style amps with 12" speakers. A nice 10" or 12" Weber or Celestion speaker can help too, Ted Weber is a pretty cool guy (http://www.WeberVST.com), just email him with your wishes and needs regarding speakers.  
 
Hope this helps, good luck with your amp!!!  
 
Chris
 
   Page 1 of 1