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Hoffman Amps Forum image Author Topic: Old f....radio revisited.  (Read 1593 times)

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Offline Colas LeGrippa

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Old f....radio revisited.
« on: February 06, 2020, 06:03:12 pm »
Hola mi friends,


A friend of mine (sometimes I have the feeling that I am experiencing one way friendship....)
 called me to fix his vintage radio. (I must learn to say NO. Next time I will, promised. ).


First of all, I don't know a single tube in there.
I am old but not THAT old. The problem is a pulsating sound like a vibrato without the guitar sound.( I had modded it a couple years ago for guitar, in fact I just had to put a guitar 1/4 imput and reroute the opt wiring). But this is not.my main concern. This "friend" wants me to install a 3 prong a/c supply cord while one side of the 6.3vac heaters is already tied to gnd. The PT has a center tap tied to gnd as well. I never coped with heaters wiring like that. Can I just ty the chassis to gnd or no ?
Don't miss the Woodstock experience : ''FORTY YEARS AFTER'' at Club Soda,  in Montreal, august the 17th and 18th and october the 27th. Fifteen musicians onstage.  AWESOME !
P.S.: call me Alvin.

Offline sluckey

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Re: Old f....radio revisited.
« Reply #1 on: February 06, 2020, 06:28:05 pm »
yes
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline Colas LeGrippa

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Re: Old f....radio revisited.
« Reply #2 on: February 06, 2020, 06:38:30 pm »
Short and sweet.
Thanx
Don't miss the Woodstock experience : ''FORTY YEARS AFTER'' at Club Soda,  in Montreal, august the 17th and 18th and october the 27th. Fifteen musicians onstage.  AWESOME !
P.S.: call me Alvin.

 


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