[amsat-bb] SDR's for satellite work, was: ===> Re: Yaesu FT-857D

Erich Eichmann erich.eichmann at t-online.de
Sun Jan 24 07:29:48 UTC 2016

Hi Clayton,
You wrote:
"The only drawback to the solution was having to swap coax lines between 
2m and 70cm. "
SatPC32 can optionally control a coax  antenna switch (called "transfer 
switch" as far as I know)  that swaps the 2m/70cm antennas between the 
radios when you switch between v/u and u/v satellites.  The DTR pin of 
the Radio 2 serial port can be used to either feed a CAT interface or to 
steer the antenna switch (selectable in menu "Options").  Mike, W4UOO, 
suggested such feature and I added it  a few months ago.
The feature requires a 1-transistor buffer between the DTR pin and the 
coax relais. There is an example on my website www.dk1tb.de/AntSwitchIF.jpg
73s, Erich, DK1TB

Am 23.01.2016 um 03:37 schrieb Clayton W5PFG:
> Graham,
> I know you specifically said you prefer Linux, but the solution which 
> brought me the most success was HDSDR+SatPC32.  The two applications 
> talk together well via CAT and a pair of virtual serial ports.  This 
> gives you full Doppler shift adjustment by computer control.
> My FT-857D was configured as a radio in SatPC32.  The FCDP+ was 
> configured as the other radio in SatPC32.
> If you moved the dial on the radio, there was full, tracking feedback 
> to SatPC32 and HDSDR.  If you tuned on the HDSDR, it adjusted the 
> radio as well.
> I made several hundred contacts on all the available satellites during 
> the time I was playing with this in the shack.
> The only drawback to the solution was having to swap coax lines 
> between 2m and 70cm.
> 73
> Clayton

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