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HEATHKIT SG-8 SIGNAL GENERATOR unknown mod?
Bradley Rush
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Joined: Oct 2011
City: Lompoc CA
#1

11-28-2016, 11:32 PM
I have a heathkit sg-8 that some one has modified
They put a 8 pin socket on the right upper side.

Pin 5  goes to pin 1 of the 12AU7
Pin 6  goes to RF out jack
Pin 7  goes to ground 
Pin 8  goes to 6.3 Vac 

I ask to find out if any knows of this mod?
 If so what tube should I get?
My guess is this tube is amplifying the RF.
(This post was last modified: 11-29-2016, 09:02 AM by Bradley Rush. Edit Reason: better title )
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Bradley Rush
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#2
Photo 

11-29-2016, 09:13 AM
This is the front of the SG-8


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Bradley Rush
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#3

11-29-2016, 09:17 AM
This is the back


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Radioroslyn
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Posts: 7,273
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#4

11-29-2016, 09:52 PM
I doubt it's a socket for an additional tube, probably for some sort of accessory. Maybe an 100kc calibrator.
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!

Terry
(This post was last modified: 11-29-2016, 09:53 PM by Radioroslyn.)
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Bradley Rush
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Posts: 220
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Joined: Oct 2011
City: Lompoc CA
#5

11-30-2016, 12:50 AM
With the signal gen  hooked up you could monitor rf plate voltage on the 12AU7 and filaments for stability?
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Bradley Rush
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Posts: 220
Threads: 56
Joined: Oct 2011
City: Lompoc CA
#6

11-30-2016, 12:00 PM
HEATHKIT SG-8 now up and going


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  1. The PHILCO Phorum
  2. Various and Sundry Categories
  3. Test Equipment