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Discussion Starter #1
Hey everyone,

Just looking for some feedback on this amp and the wiring. A gentleman offered it to me as a trade and vintage amps are not an area I'm knowledgeable in.

Chassis Serial number C17814

344093
344094
344095
344096
344097
344098
344099
 

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Speaker replacement, obviously. The wires running out of the power transformer aren't what I'd expect from something of that vintage either so I'd guess the PT was replaced as well. Would need to see the underside of the chassis to know for sure though.

EDIT: The PT mount bolts are clearly new so it's almost certainly a replacement.
 

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Discussion Starter #6
I really don't know how to read schematics.

I'm kind of gathering that this might not be all its talked up to be by the other party? Is it safe to say the value of this would probably not be very high if most of the board has been swapped out?
 

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Is it safe to say the value of this would probably not be very high if most of the board has been swapped out?
The tweed looks really nice however the replacement of several original components (especially the PT) mean this would never fetch top dollar. $1K or less perhaps?
 

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Discussion Starter #8
The tweed looks really nice however the replacement of several original components (especially the PT) mean this would never fetch top dollar. $1K or less perhaps?
I really appreciate the feedback on this post and the learning opportunity. Y'all are great
 

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Power transformer and speaker change would be the only real concerns. Having the electrolytics already done is a plus to me. Of course that all depends on how the amp is presented and priced.
 

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Power transformer and speaker change would be the only real concerns. Having the electrolytics already done is a plus to me. Of course that all depends on how the amp is presented and priced.
Those molded blue caps in the Tweeds have that $$$ Mojo though.
 

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Schematic. Cathode cap for 6V6 is higher value.

View attachment 344115
47 mfd.
Original is a 25 mfd
It is not a big issue if you like the tone. $3 for a good F&T cap with original value.

There is a cathode caps / bypass cap on the bias 1500 ohms resistor at 12AX7 .
Original don't have. This give more gain to the amp.


Blue filter caps are good quality one. Too many people put low cost far east caps.
I have fixed lot of vintage amps.

To resume, amp look in good shape but lost is value 'cause no original speaker

Capture d’écran, le 2021-01-06 à 04.21.57.png
 

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No pictures of the transformers has me curious....just saying. That said, what I can see, the power transformer appears to be a replacement as others have suggested.
 

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Power trans - centre tap instead of two x 100ohm resistors doesn't seem right for this amp (and isn't on that Fender layout)

Also, first filter cap should be 16uf not 8uf, (Fender layout is showing one 16 and two 8's)
 

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If the power transformer has been replaced , it looks like a good job was done . But without seeing the date code , hard to say . Solder joints look like they could be original on the rectifier tube socket and where the high voltage center tap and one side of the filament winding are soldered to the chassis . Tweed Champs had one side of the filament winding soldered to the chassis , as in this amp . There isn't a 6 volt center tap that I can see , and there would be no reason to put the100 ohm resistors on the heater winding since one side is going to the chassis . Interesting to see the blue coupling caps , must be a very late Tweed Champ . 63 maybe ? The handful of examples I have seen also have the bypass cap on the first triode cathode , though it doesn't show up on the schematic . FWIW .
 

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I really don't know how to read schematics.

I'm kind of gathering that this might not be all its talked up to be by the other party? Is it safe to say the value of this would probably not be very high if most of the board has been swapped out?

Right.
It's a good amp with good parts.
Good player not more.
 

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If the power transformer has been replaced , it looks like a good job was done . But without seeing the date code , hard to say . Solder joints look like they could be original on the rectifier tube socket and where the high voltage center tap and one side of the filament winding are soldered to the chassis . Tweed Champs had one side of the filament winding soldered to the chassis , as in this amp . There isn't a 6 volt center tap that I can see , and there would be no reason to put the100 ohm resistors on the heater winding since one side is going to the chassis . Interesting to see the blue coupling caps , must be a very late Tweed Champ . 63 maybe ? The handful of examples I have seen also have the bypass cap on the first triode cathode , though it doesn't show up on the schematic . FWIW .
actually I see you're correct!
 

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For as much work as seems to have been done, is there any chance it’s not Fender? It is really clean, almost too good to be true for a tweed.
 
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