[MRCA] AN/GRC-9 Keying in Phone Position

[WA5CAB at cs.com]

If it takes more than a second or so for the transmitter to come up in Voice, 
there's something wrong with the transmitter.  If a second or so is too long 
to wait to say something, you're in the wrong hobby.

Almost all if not all of the tube-based military portable sets and a lot of 
the vehicular ones turn off unnecessary tubes when they are not in use and the 
equipment is set for voice or RATT operation.  The reason should be obvious, 
but it is to save power, whether battery, man (and food), or gasoline/diesel.  
As Perry points out, it isn't practical to do that when operating CW.

In a message dated 8/3/2006 8:19:51 PM Central Daylight Time, w8au at sssnet.com 
writes: 
> At 07:32 PM 8/3/06, Bill Ramsey wrote:
> >   The normal wiring for the AN/GRC-9, when in Phone position, turns the
> >filaments of the transmitter stage off. In MCW or CW positions, the
> >filaments stay lit allowing for quick keying. I am sure there is a 
> >reason for this, but I am not sure what it is (heat reduction?).
> 
> Simple:  the delay would kill any dits and maybe even the dahs.
> 
> >Anyway, is there a published "safe" modification for the keying/mode
> >wiring that allows for faster keying times when in the Phone 
> >position? (It takes a while for those filaments to warm up. Hard to 
> >be heard that way. :)
> 
> Usually not a drawback to have a short delay on Phone.  But you could
> rig it to have continuous filaments on Phone, too.
> 
> (As long as you're running an AC ps, the guy cranking the hand gennie 
> won't complain)  :-)
> 

Robert Downs - Houston
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MVPA 9480
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