[Moon-net] Pair of 2MXP20's?

[Edward R. Cole]

At 02:05 PM 12/16/2006 -0500, Edward J White wrote:
>
>Joe:
>Why 2 CA-144 amps?
>I use two feedlines one receive and one transmit I then connect the ARR
amp at the end of the receive line before it goes into a T/R relay then
into a H & V transfer relay to the splitters. 
>Ed
>WA3BZT

Ed,

Joe explained why two preamps.  

But with the system as you have it your Tx and Rx are tied to the same
polarity.  My system takes extra relays (4) but permits chosing Rx and Tx
pol independent of the other (i.e H/H, V/V, H/V, V/H).  I was using two
preamps and combining the outputs for one Rx coax line.  I changed Rx pol
by powering one or the other preamp.  With the addition of phase shifters
and potentiometer continous pol rotation was possible.

I had one old preamp die so I modified my system back to one preamp with a
polarity coax relay for chosing H/V on Rx.  This is fairly adequate and I
will consider making a duplicate of my "WA5VJB" mgf-801 preamp later this
year.  I will be experimenting with the SDR-IQ in a month or so and
eventually would like two of them for a system like Joe has set up using
Linrad.

EME Status:  Winter storm has blown in with winds keeping me off my tower
so still do not have my 7/8-inch Tx line re-connected for 2m-eme.  Hoping
maybe they will die down tomorrow, but may end up waiting until next
weekend to fully restore the eme system.  Currently running only 54w to
antennas due to 4.9-dB loss on test coax line used (RG-58&LMR-400).
7/8-inch Heliax exhibits only 1.7 dB loss providing 115w at the antenna array.
73's,
Ed - KL7UW  
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http://www.qsl.net/al7eb - BP40iq 
144-EME: FT-847, mgf-1801, 4xM2-xpol-20, 170w (QRV)
432-EME: Not QRV
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