[Milsurplus] SRR-12,13 Muting?

[Robert P. Meadows]

The SRR13 standby/operate switch supplies B plus to V501, the first RF amplifier/preamplifier.  The radio has a fast acting current relay to protect the RF input from strong transmitter signals.
To "mute" the receiver, simply add two wires to the standby/operate switch, bring them to rear connector shelf, and either add a proper connector, or remove an IF or PAN connector and install your two pin connector there.  Place the operate/standby switch in standby, and using a relay, close the circuit brought to the rear panel for operate, a simple mod.
OR, just use the operate/standby switch when transmitting.
Switching the entire B plus line will cause stability problems.
R

-----Original Message-----
From: milsurplus-bounces at mailman.qth.net <milsurplus-bounces at mailman.qth.net> On Behalf Of Mike Morrow
Sent: Tuesday, January 28, 2020 11:17 PM
To: milsurplus at mailman.qth.net
Subject: Re: [Milsurplus] SRR-12,13 Muting?

AN/SRR-12, -13, -13A receivers have seven connectors on the rear, but no muting circuits.  You may be thinking of the R-105*/ARR-15 with those muting connections on its one rear connector.

I have an AN/SRR-13A from NAVMARCOR MARS that I last used with a transmitter in 1970.  I used an external relay that on transmit grounded the receiver antenna input connection and switched the antenna to the transmitter...not perfect but better than making internal mods to the receiver.  For more than five years I carted it and an HW-101 in my Opel Manta duty station to duty station from California to Maine and several points in between.  I doubt it would have survived the typical military household goods shipment.

Mike / KK5F

-----Original Message-----
>From: jphutch60bj <jphutch60bj at gmail.com>
>Sent: Jan 28, 2020 8:25 PM
> I may be wrong?  I seem to remember having to short two pins on the 
>back connector.
>
>On 1/27/2020 11:33 PM, Robert Goff wrote:
>> I'm curious if anyone is using one of these as their main station 
>> receiver and what they might have done for muting during transmit.
>>
>> Usually I take the old National approach and break the B+ with a 
>> relay.  In this case I don't know where I could fit one in a very 
>> densely packed chassis.
>>
>> Any thoughts or experience to share?
>>
>> Thanks,
>> de Robert W7MKA
______________________________________________________________
Milsurplus mailing list
Home: http://mailman.qth.net/mailman/listinfo/milsurplus
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Milsurplus at mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html Message delivered to rpmeadow at bellsouth.net