[Milsurplus] RAX nix surveillance

[Mike Morrow]

Dave wrote:

>I don't have my RAX manual handy, so I may 
>not remember this correctly, but isn't the RAX the
>set in which the manual diagrams show no sidetone 
>connection and no muting circuit?
>If so, that's quite an "oops" for something
>intended to be a liaison set.
>In fact, it would flat disqualify it.

But Dave, none of the RU sets that were companions to the
GO- and GP-series of transmitters have ANY receiver muting
during transmission except that provided by the antenna
relay in the GO- or GP- disconnecting and grounding the 
receiver antenna path.

The same applies to use of the ARB with the ATB, ATC, or ATD.
The ARB doesn't have a muting setup the way the BC-348 has.

The USN philosophy didn't seem too big on bona-fide receiver
muting of the type that the USAAF used for the BC-348 in the
SCR-287 and AN/ARC-8 systems.  

At least the USN practice allowed the receiver to be adjusted to
the transmitter during transmit, without needing a MONITOR-NORMAL
switch in MONITOR position such as is used in the the SCR-287 and
AN/ARC-8.

Even the "command set" receivers don't get muted on transmit.
Relays in the receiver rack just disconnect the receiver audio
output from the audio bus and connect a sidetone from the modulator
to the audio bus during transmit.  (That's why there's no way to
net a command set receiver to its associated transmitter by tuning
for the transmitter signal in the receiver during transmit.)

Mike / KK5F