[ARC5] Force Feeding Audio into a T19/ARC-5 to Make It Sing for Its Suppe...

[WA5CAB at cs.com]

RM-12 is part of RC-47.  The other major component is RM-13.  Used with but 
not part of SCR-188-(*).  Manual on RC-47 is TM 11-312.  Original manual 
$20 shipped CONUS & Territories.

Robert D.

In a message dated 01/12/2013 09:57:34 AM Central Standard Time, 
aj1g at sbcglobal.net writes: 
> Having fun lately feeding high quality audio into my otherwise stock 
> BC456 
> screen modulated T19/ARC-5.  I have been truly amazed as to how good these 
> 
> things can sound, and how nice the mod waveform looks on a scope.  Been 
> using an 
> old RM-12 remote control unit and feeding audio from a small utility amp 
> with a 
> 25V  line output onto the RM-12 Line 1 landline input terminals.  Also 
> heavily 
> loading the RF output circuit with the KJ4KV RF autotransformer circuit, 
> that 
> makes a big difference in the modulation linearity and max positive peaks 
> percentages attained vs just coupling  a coax 50 ohm load into the antenna 
> 
> terminal via a series cap.  Playing "test audio" in to this setup using a 
> dummy 
> load shows really clean low end and highs, a pleasure to listen to on a 
> good 
> stereo system fed by the R-392.  Better sounding than some of the local FM 
> 
> outlets around here!  Getting about 15 watts carrier out when adjusted for 
> best 
> audio quality.
> 
> Interested in learning more about how the RM-12s were used in the field.  
> As far 
> as I can tell, the T/R switching must be done locally at the transmitter 
> by an 
> operator with it, making it more of a phone patch than a true remote 
> control 
> unit. How was the true remote operation, including the T/R switching from 
> a 
> remote location done, was there another unit besides the RM-12 used in the 
> RC-?? 
> system, or was there some DC switching voltage carried over the twisted 
> pair 
> feeding into the RM-12? Is there an RM-12 TM or  other documentation out 
> in 
> cyberspace?
> 

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