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<DIV>David and all</DIV>
<DIV> </DIV>
<DIV>I have been using K5SO diversity software for quite some time now, months,
and</DIV>
<DIV>during this time I have transitioned from using 2 horizontal antennas (80
meters),</DIV>
<DIV>to using 3 selectable RF probes. I am trying to document the hardware
aspect of</DIV>
<DIV>my setup and let the software speak for itself. </DIV>
<DIV> </DIV>
<DIV>I am still experimenting with different antennas at this time, but bad
weather has</DIV>
<DIV>slowed my progress. My initial tests with the 2 horizontal antennas on 80
meters</DIV>
<DIV>proved to be quite effective bringing DX signals "out of the noise"
certainly by</DIV>
<DIV>minimizing louder signals from a different direction. Also found it quite
effective</DIV>
<DIV>to eliminate "birdies" and "UFOs" caused by switching power supplies
etc.</DIV>
<DIV> </DIV>
<DIV>I have since gone to using 3 RF probes set up in an equal lateral triangle
about</DIV>
<DIV>50 feet apart. These probes are nothing more than 3 inch square pieces of
</DIV>
<DIV>double sided PC board connected directly to a high impedance unity
gain</DIV>
<DIV>amplifier feeding RG-6 back to a software selectable (ALEX control)
switching</DIV>
<DIV>system that not only provides any two of six selectable inputs, but also
provides</DIV>
<DIV>RF protection for the Mercury boards. (The RF probes are about 20 feet in
the air)</DIV>
<DIV> </DIV>
<DIV>The beauty of the RF probes is that they are NOT resonant, and believe it
or not, </DIV>
<DIV>they perform much better than any of my wire antennas in the Broadcast
band</DIV>
<DIV>and work well from about 300 Khz to 20 meters. </DIV>
<DIV> </DIV>
<DIV>During the daytime, I can null a local broadcast station (13.5
miles away) by more</DIV>
<DIV>than 50 dBm and this holds pretty steady. However as time progresses into
</DIV>
<DIV>darkness and ground wave starts to fade and sky wave increases, the null
goes</DIV>
<DIV>down somewhat to around 30 dBm.</DIV>
<DIV> </DIV>
<DIV>Using diversity at night on 160 and 80 meters varies with propagation, and
using the</DIV>
<DIV>same probes, I see anywhere from 10 dBm to 25 dBm null, but this is very
dynamic</DIV>
<DIV>given the variations of the received sky wave. </DIV>
<DIV> </DIV>
<DIV>My plan is to try some larger (20 foot) probes and evaluate them when the
weather</DIV>
<DIV>allows. Then I will try 3 resonant verticals as well. </DIV>
<DIV> </DIV>
<DIV>I find I use the RF probes on 80, 40 and 20 meters more than I use the full
sized </DIV>
<DIV>antennas. They are very useful on 20 meters when I am talking to Europe
and</DIV>
<DIV>NA stations at the same time, as I can rotate the diversity control to
"peak" up</DIV>
<DIV>the station in one direction and just click 180 shift for the other. I
do run full legal</DIV>
<DIV>limit on these bands, thus the need for protecting the Mercury boards even
though</DIV>
<DIV>the RF probes are 100 yards from my transmit antenna.</DIV>
<DIV> </DIV>
<DIV>In conclusion, I find the diversity software extremely useful, and
intriguing to experiment</DIV>
<DIV>with. I also would like to hear from others about their experiences
and how they </DIV>
<DIV>use it. If anyone has any other questions regarding my set up, I will
be happy to </DIV>
<DIV>respond.</DIV>
<DIV> </DIV>
<DIV>I want to thank K5SO & W5WC for their continuing improvements of the
PowerSDR</DIV>
<DIV>software as applied to HPSDR, and of course thanks to FLEX radio and KD5TFD
as</DIV>
<DIV>well. </DIV>
<DIV> </DIV>
<DIV>73 de Joe</DIV>
<DIV>K1RQG </DIV>
<DIV> </DIV>
<DIV>
<DIV>In a message dated 3/8/2011 2:00:01 P.M. Eastern Standard Time,
dwoodhead@bms-inc.com writes:</DIV>
<BLOCKQUOTE style="PADDING-LEFT: 10px; MARGIN-LEFT: 10px"><FONT style="BACKGROUND-COLOR: transparent" face=Arial color=#000000 size=2>*****
High Performance Software Defined Radio Discussion List *****<BR><BR>For
anyone that is using dual Mercury boards in a diversity setup;
how<BR>effective do you find it in suppressing local and distant QRM (using
2<BR>antennas)?
<BR><BR>Thanks<BR><BR>David<BR>KM5TZ<BR>_______________________________________________<BR>HPSDR
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