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RE: Field Day weather/results



Art wrote:

	My question is about InstantTune. I had a lot of trouble
	setting it up for FO-29. At first, I couldn't get it to even
	talk to our FT-847 because it had been set for 9600 baud.
	The settings were right but no comms. On Sunday AM I got it
	talking at 4800 but it started out in the wrong mode (CW I
	think) and at the end of the passband instead of the middle.
	And when I tuned to mid-band, it kept changing the Tx
	frequency back to the edge. I couldn't seem to find the
	right combination of parameters.

	So, can you tell me:

	1. What were your IT params for the Fuji birds?
	2. What rig were you using?
	3. Do you think the RHCP antennas were an
	advantage/necessity?

Wayne replies:

InstantTune works great with the Fuji birds on my FT-847 using the default
frequencies in the ITUNE.CFG file.  Yes, the FT-847 must have the CAT rate
set to 4800 baud in the menu.  I kind of like the fact that it starts on the
beacon frequency.  That way I can confirm if the satellite is really there
and working.  You can change the default RX frequency for each satellite by
changing the "beacon" frequency in ITUNE.CFG.  You can also change the
default mode from CW to USB if you want.  I start in CW mode so it's
convenient to send a string of dits to verify that the frequencies are
correct.  For some reason the tuning isn't quite the same in CW and USB
mode.  To get the up/down frequencies to match in SSB, I must send a string
of dits and tweak the TX frequency so that the returned signal is about 800
Hz HIGHER pitch than my own CW sidetone frequency.

Perhaps your InstantTune problem was caused by the "VFO tracking" function
on your FT-847.   "VFO tracking" MUST BE OFF for InstantTune to work
correctly.  InstantTune provides "virtual" VFO tracking by polling the RX
VFO frequency as you tune, and then computing and writing the correct new TX
VFO frequency 2 seconds later.  InstantTune sends a CAT command to put the
FT-847 in satellite mode, but there is no Yaesu CAT command to
enable/disable VFO tracking.  When you start InstantTune, the "tracking"
state ends up being the same as whatever it was the last time the radio was
in satellite mode.  This can be a problem if you use the FT-847 satellite
memories a lot, because you probably have tracking enabled in most or all of
your satellite memories.  To solve this problem I created a "dummy"
satellite memory called "ITUNE" which has tracking disabled.  I leave the
FT-847 on this satellite memory all the time so that InstantTune will work
correctly.  I never use the FT-847 satellite memories nowadays.  The
InstantTune "memories" are more convenient because they automatically put
the radio on the correct frequencies for the satellite that is displayed by
InstantTrack.

Regarding antennas, I don't think RHCP antennas are necessarily an advantage
for the Fuji birds.  I get deep fades with my RHCP antennas because the Fuji
birds are sometimes LHCP.  I haven't tried it, but I suspect that linear
polarization would be just as "okay" as RHCP.  Truly good reception of the
Fuji birds requires RHCP and LHCP, independently selectable on the uplink
and downlink antennas.

Wayne Estes W9AE
Mundelein, IL, USA
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