[Hallicrafters] SX-71 Question

[Richard Knoppow]

----- Original Message ----- 
From: "Duane Fischer, W8DBF" <dfischer at usol.com>
To: "Bill McCourt - WF1L" <wemccourt at yahoo.com>; 
<hallicrafters at mailman.qth.net>
Sent: Tuesday, January 18, 2011 1:28 PM
Subject: Re: [Hallicrafters] SX-71 Question


> Bill,
>
> When you get the issues resolved, please print them to 
> this list so that
> others can benefit too. Thanks!
>
> ----- Original Message ----- 
> From: "Bill McCourt - WF1L" <wemccourt at yahoo.com>
> To: <hallicrafters at mailman.qth.net>
> Sent: Sunday, January 16, 2011 4:55 PM
> Subject: [Hallicrafters] SX-71 Question
>
>
> Hi,
>
> Maybe this a question you've responded to before but, is 
> there a circuit to
> mute the SX-71 when it's used with a transmitter?
>
> Is it just a matter of replacing the existing Octal jumper 
> plug on the
> chassis backplane with an external pair of wires to a set 
> of external
> contacts on a DOW-KEY TR relay like my Hammarlund? Didn't 
> see any reference
> to a Transceiving arrangement in the manual.
>
> Bill - WF1L
>
    The manual shows that the accessory plug on the back has 
leads in parallel with the  contacts on the standby switch. 
A relay can be used across these terminals to deactivate the 
receivers in transmit. I suggst using a small relay right at 
the receiver to avoid having long leads with B+ on them. The 
wiring can probably be made to the current dummy plug. To 
use it the Receive-Standby switch should be left in Standby 
unless you want to monitor your own transmissions.


--
Richard Knoppow
Los Angeles
WB6KBL
dickburk at ix.netcom.com