[Icom] Icom 756PRO as Receiver Only

[Bill NY9H]

for what it worth, this is a reply I received from a friend at ICOM JA 
regarding the
use of the 756 as a 2nd rcvr:


I asked one of our Engineers about your question, and here is what he said.
This is a direct translation of the procedure, so if it is a little
difficult to understand, please don't hesitate to ask me for more
clarification.

Here goes:
The IC-756PRO and 756PRO2 do not have mute terminals. As for receivers,
there are situations where it is matched with a transmitter, therefore often
a mute terminal is employed. To mute the IC-756 and 756PRO2, please do the
following.

By applying 8V to the transverter terminal (pin-6 in ACC2 socket), the
transceiver becomes the transverter exciter. By doing this the PA unit
becomes inactive. Next put the transceiver into the transmit condition.
(Pin-3 ACC1 socket/pin-3 ACC2 socket). During receive, the voltage is 8V,
but when the voltage becomes 0V, the transceiver is activated to the
transmit condition.

When the transceiver is acting as a transverter, the RF input/output is as
explained on pg 12 of the Instruction manual (I think this is the IC-756PRO2
manual). By connecting a 50 ohm dummy load to this terminal, even if
transmit is activated, the heat generated by the dummy varies and since the
PA unit is not active, even very low RF feedback will probably not occur.
This terminal's output is - 20 dBm.

The most important thing is that actual muting of the receiver (circuit)
cannot be done, so when you wish to mute the transceiver, it is necessary to
put it into transmit condition during that time only (means the time you
wish to mute the trxer). When the transceiver is in transmit condition, the
PA unit is active, so consideration of carrier leakage is necessary, however
by making the transceiver the transverter exciter, no consideration for
carrier leakage is needed.

Note from the Engineer: The concept of a receiver and a transceiver is
generally different, so it is not good to assume that they will operate the
same.


bill


At 10:17 PM 5/22/03, you wrote:

>First thing that comes to mind:
>
>1. set the Break-In  to Off
>
>2.turn on the PRO PTT or "transmit" when you turn on the external
>transmitter to send.
>
>Without getting out the schematics, I *think* that should disable the PRO
>transmitter and disconnect the receiver from the antenna it may be connected
>to when you "transmit.".
>
>However, be a good idea to get out the manual and check this for yourself.
><:}
>
>73/72, George
>Amateur Radio W5YR -  the Yellow Rose of Texas
>Fairview, TX 30 mi NE of Dallas in Collin county EM13QE
>"In the 57th year and it just keeps getting better!"
><mailto:w5yr@att.net>
>
>
>
>
>
>----- Original Message -----
>From: "Ron Evans" <cosmos41@ix.netcom.com>
>To: <icom@mailman.qth.net>
>Sent: Thursday, May 22, 2003 4:23 PM
>Subject: [Icom] Icom 756PRO as Receiver Only
>
>
> > Wanting to homebrew a low-power cw xmtr and just use my 756PRO as the
> > rcvr.  (Not always...but on those occasions when I feel like using the
> > homebrew xmtr)  To make everything easy, assume separate antennas.  The
> > question is:  Is there any easy way to get the equivalent of "Standby"
> > by using any of the bells and whistles on the 756PRO?  I fear "beasts"
> > be lurking in these waters and knew that the Icom guys could lead me
> > through the murky depths.  Thanks in advance for any help.
> >
> > 73,
> >
> > Ron
>
>----
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