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FT-847 and CAT re visited



Firstly thank you all for the feedback on how YOU handle the 
"PKT RATE"  scenario. I will include your comments in the
distribution documentation.

One of the major design concepts of my UNI-TRAC system was to
allow any one of the 23 presently interfaced rigs to be "mixed and
 matched", in any down or uplink combination, on a satellite by satellite
 basis. In other words the satellite to be tracked has its own specific
configuration file. In that file parameters are defined as to
how the combination of rigs, baud rate of serial communication to the 
rigs, mode of operation, doppler shift counting gate limits, pass bands
for various analog satellites, which port to use from the UNI-TRAC 
card, etc etc. are setup. This feature allows COMPLETE control of the
 rig/s from a software base.

The design premise to achieve  an unattended fully automatic 
satellite ground station was that  there should be no need for the
user to have to specifically set  up a rig for a particular satellite
operation. Let the software do it.. This of course is quite easily
achieved when using Icom, or Kenwood equipment. Yaesu to my
mind have always "missed the boat" on CAT control and  I purchased
the FT-847 ( to add to FT-980, FT_736R, FL-7000) purely to test out
the interface. I was disappointed to say the least to find no vox,
no CATcontrol over the PKT RATE, no CAT control of split mode,
no CAT control or ability to produce doppler controlled up and
downlink same band simplex for MIR type operation, no CAT control
of memory functions, etc etc. The competing rigs can do all of this
with ease.

The above statements are the basis on which I modified the FT-847
to bring it into line with the design criteria. As I said in the original
document   the modification only applies for unattended automatic
ground station usage really.

Here is an example of an actual installation.

I have a user whose location is completely surrounded by low hills.
Atop a hill some 3 miles from the location is a water pumping station
from which there is a 360 degree "clear satellite view". The pump
house is supplied with mains voltage plus a dedicated modem line for
pumping  supervision.

The entire satellite station and  terrestrial packet link are housed 
in the pump house along with a Pentium II 300. The satellite operation
runs 24 hours per day, 360 days per year remotely,  with occasional
visits for preventative maintenance. The link to the homestead is via
modem and the PC Anywhere for Windows software. The computer's
clock is continually corrected from UO-22, and UNI_TRAC searches in a
particular directory for the latest version of keplerian elements 
downloaded automatically. At any time via the modem link the remote
station can be be reconfigured purely by sending an amended
text configuration file to the computer. i.e. Change the main rig
from the FT-847 to the IC-271/IC-471 pair, or point the antenna
system to a different terrestrial repeater after satellite LOS etc.

This all happens using the "plain vanilla" UNI_TRAC system.

By the way. I see a comment about "my commercial software".
To coin a phrase this is only about 2% correct. I am 70 and
developed this project as a hobby and as a method of preventing
the grey matter from solidifying. The charges for the product are
reasonable and may some day put me in the red. I am NOT using
this reflector as an advertising channel.

73

Dave Lamont        ZL2AMD           http://qsl.net/zl2amd/


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