[ARC5] Any difference in the front plugin pin out on CCT-46104

[WA5CAB at cs.com]

The CBY- and CCT-46104 covers 1.5-3.0 MC and are from the ARA set.  There 
is no SCR-274-N Equivalent as the AAF didn't buiy any.  R-25/ARC-5 is 
equivalent.  However, all of the ARA and SCR-274-N receivers have substantially the 
same circuits except for varying component values in the different 
frequency receivers.  The exception is that the audio output impedance of the ARA 
receivers is around 500 ohms.  The A-models of the SCR-274-N are 4000 ohms.  
And the B-models can be connected for either 4000 or 250 ohms.

The ARA and SCR-274-N receivers all have a rudimentary AGC system sensitive 
only to signals whose amplitude is sufficient to drive the 2nd IF tube into 
drawing grid current.  The AN/ARC-5 receivers have a more conventional AGC 
system except that the diode rectifier is in the 12SF7 2nd IF tube.  But in 
any case, nothing to do with either system connects to the front connector.  
So if the 2nd switch was supposed to turn off the AGC, it was a mod.

Robert Downs - Houston
wa5cab dot com (Web Store)
MVPA 9480

In a message dated 09/08/2017 17:34:10 PM Central Daylight Time, 
arc5 at mailman.qth.net writes: 
> I thought these were close to, or maybe the same as the SCR-274 system?
> I have no info on these. Is this an ARA designation?
> 
> 
> The reason i ask is the original owner had a volume control, BFO switch 
> and another switch ( not power).
> There were pencil notes inside the cavity labeling the pins for "BFO" and 
> "AVC".
> Is this original or something the guy modified?
> 
> 
> 
> 
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/arc5/attachments/20170908/ed97e56b/attachment.html>