Problem with multiple antennas
Posted: Thu Jul 05, 2018 2:40 pm
I have two receiving only antennas: a 300-foot Beverage and a nine-foot active vertical. They each plug into ANZAC splitters. Those run, for RX1, to PowerSDR antenna inputs 2 and 3, and for RX2, to an Alpha-Delta switch that controls whether RX2 receives from the Beverage or the vertical.
I work a daily MARS net, usually near 60 meters but sometimes near 75 or 40 meters, and switch receiving antennas often, on RX1 by clicking and on RX2 by mechanical switch. I use MVAC, with VAC1 using the UMC ASIO Driver into my 202HD, and VAC2 using MME into an M110A decoder.
This works well so long as RX1 and RX2 are on different antennas. If, however, they are on the same antenna then the signal for RX2 is greatly attenuated. I can see it on the panadapter, with both signal and noise floor dropping, with noise down 10-15 dB and signal disappearing into the noise. RX1 is not affected.
Any ideas why this might be happening and how it could be addressed? Thanks.
Buck ko0y
I work a daily MARS net, usually near 60 meters but sometimes near 75 or 40 meters, and switch receiving antennas often, on RX1 by clicking and on RX2 by mechanical switch. I use MVAC, with VAC1 using the UMC ASIO Driver into my 202HD, and VAC2 using MME into an M110A decoder.
This works well so long as RX1 and RX2 are on different antennas. If, however, they are on the same antenna then the signal for RX2 is greatly attenuated. I can see it on the panadapter, with both signal and noise floor dropping, with noise down 10-15 dB and signal disappearing into the noise. RX1 is not affected.
Any ideas why this might be happening and how it could be addressed? Thanks.
Buck ko0y