[Towertalk] Transfer switch

[Paul Playford]

I made my own box for SO2R.

The logic that I required (and achieved) is:

automatic radio switching under control of CT

manual override switch

normal: left transciever transmit and receive in left ear (headphones),
right radio receive in right ear

when I operate the manual switch (center off) to the left, I hear the left
radio in both ears and transmit on it.

when I operate the manual switch to the right, I hear the right radio in
both ears and transmit on it.

When using CT, "<ctrl> ," (that's press the CTRL key and comma key at the
same time) toggles between normal operation and right radio only.

During receive the antenna goes to both radios.  The double termination
changes sensitivity.  Depending on the cable lengths between the antenna
relay and the receivers it may increase sensitivity or decrease sensitivity.
A better way would have been to build a splitter but that also would make
antenna switching more complicated.

While transmitting on either radio the antenna and receive audio on the
opposite radio is interrupted.

And my microphone, cw keying and amplifier keying leads automatically switch
between radios.

My monobanders are switched seperately under control of the left radio
always.  Works great for SO2R single band contesting and split frequency
DXing.

And it was not cheap or easy.

I did have one advantage, I know what brand my radios are and will stick
with that brand so I don't have to worry about switching interfaces for
other brands.  Maybe there is a reason Array Solutions, Top Ten Devices and
Acom are not less expensive.

de Paul, W8AEF

----- Original Message -----
From: "Pete Smith" <n4zr@contesting.com>
To: <K4FJ@aol.com>; <w6ter@worldnet.att.net>; <towertalk@contesting.com>
Sent: Tuesday, November 26, 2002 2:11 AM
Subject: Re: [Towertalk] Transfer switch


> At 05:36 PM 11/25/02 -0500, K4FJ@aol.com wrote:
> >In a message dated 11/25/2002 3:54:55 PM Eastern Standard Time,
> >w6ter@worldnet.att.net writes:
> >
> > > Two ideas, Pete.
> > >
> > > Array Solutions and Top Ten Devices make such switching arrangements.
> > >
> > > Gerry
> >
> >And, so does Acom.
> >
>
> Hey, I said less expensive....
>
>
> 73, Pete N4ZR
> Sometimes a tower is just a tower
>