[MAMS] 5.7 GHz rainscatter question

[Zack Widup]

Danny has the 5760 MHz bilateral transverter designed by KK7B. There is
only one mixer, used both on transmit and receive. It has one input and one
output. If you're an ARRL member and signed in at the ARRL website, you can
see the article here:

http://p1k.arrl.org/pubs_archive/86168

The only way to make this work with an external LNA on receive and power
amp on transmit is to use some sort of relays to separate the signals.

I built this one:

http://www.w1ghz.org/QEX/A_Single-board_Transverter_for_5760_MHz.pdf

This uses two mixers and separate transmit and receive lines. It's easier
to work with.

73, Zack W9SZ


On Wed, Aug 8, 2012 at 12:38 PM, Dr. Gerald N. Johnson
<geraldj at weather.net>wrote:

>
>
> On 8/8/2012 12:12 PM, Danny Pease wrote:
> > I see I can get a couple of boards and devices from a seller on Ebay for
> 1
> > watt out for a very reasonable price, but I was pretty sure that 1 watt
> and
> > the 18 inch dish I have would be a little on the weak side plus having to
> > split the single output of the transverter into separate TX and RX for
> the
> > amplifier and preamp, meaning a decent pair of relays or PIN diode
> switches.
> > I am getting a little antsy to try this stuff out and I am pretty sure
> the
> > few milliwatts I have available won't get me too many QSO's from around
> > here.
> >
> > Danny NG9R
> > EN40la
> >
> >
> Bigger dishes aren't difficult to acquire. Look for a 30" at a farm that
> used to get data from DTN on KU satellite. Or Channel Master dishes are
> sold on line at reasonable prices (though any price is infinitely
> greater than free).
>
> Can the Tx and Rx lines be separated inside the transverter, and their
> combining relay moved outside? The only case of them being inherently
> combined thatt I can think of is seeing the mixer directly which means
> poor receiver sensitivity and minuscule Tx power.
>
> Sometimes suitable relays can be had at reasonable prices like from
> Hangar 18 Surplus. The may take 28 volts though.
>
> 73, Jerry, K0CQ
> ______________________________________________________________
> MAMS mailing list
> Home: http://mailman.qth.net/mailman/listinfo/mams
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:MAMS at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>