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Hoffman Amps Forum image Author Topic: another skylark  (Read 2904 times)

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Offline shooter

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another skylark
« on: March 14, 2016, 08:37:45 pm »
 acquired this from a starving musician :icon_biggrin:  Very clean, plays well, just needs the 2 dead bee guts cleaned off, and scratchy pots cleaned.  Gonna spec it against the schematic and see where it's at.  Way better than the last 3 I fixed!  It's the odd one, 6EU7, 6C4, and interstage tranny PI
Went Class C for efficiency

Offline eleventeen

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Re: another skylark
« Reply #1 on: March 14, 2016, 08:46:48 pm »
Clean little dude. Did the others you looked at have those radial (PC mount) caps or do you think those new(ish)?

Offline PRR

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Re: another skylark
« Reply #2 on: March 14, 2016, 08:57:39 pm »
> do you think those new

You can see the rivet holes where the old flex-lead strap-mount caps were removed.

Still don't believe that can be a Gibson. I can almost read the whole circuit at a glance. Where is the messy maze?

Offline pullshocks

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Re: another skylark
« Reply #3 on: March 14, 2016, 09:34:45 pm »
I always have liked the looks of Gibson amps from that era

Offline shooter

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Re: another skylark
« Reply #4 on: March 15, 2016, 08:44:15 am »
Quote
Where is the messy maze?
:l2:  You are right, when I opened it, I was amazed, The other 3 I worked on looked like my early spaghetti days!  All the wires, soldering, components,  looks *original*, except the cap-3prong mod.
Went Class C for efficiency

Offline sluckey

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Re: another skylark
« Reply #5 on: March 15, 2016, 09:26:11 am »
Here's the schematic for the "whiteface" GA5T in case you don't have it. They can be hard to find...
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline Ed_Chambley

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Re: another skylark
« Reply #6 on: March 15, 2016, 11:31:47 am »
I love those little amps and this one looks nice.  Original speaker still working well?

Offline shooter

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Re: another skylark
« Reply #7 on: March 15, 2016, 12:43:11 pm »
Thanks Steve, ya, it took me like 4days of surfing last year when that model came in.  I was fascinated with the tranny PI, so I bought one and incorporated it into my last build, way less parts to solder :icon_biggrin:

The speaker sounds good, I think this amp just sat in a closet for along time.
Went Class C for efficiency

Offline shooter

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Re: another skylark
« Reply #8 on: March 15, 2016, 03:48:37 pm »
Here's the info I got from the amp, still need to tension sockets, and the bass pot won't cleanup, but it only scratches when you turn it :icon_biggrin:

EDIT: I did change the time-base on the scope, no weirdness on the OT :icon_biggrin:
Went Class C for efficiency

 


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