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Re: portable operating technique with Arrow



>From: Busch Thomas H CNIN <Busch_T@crane.navy.mil>
>First, don't "wave the Arrow," point it.  Satellites move fast, but not
>so fast.  Doppler shift is not that fast either.  The only tricky part
>is remembering to shift the active channel on my TH-D7 to the downlink
>when I need to change frequency due to doppler; then remembering to
>switch the active channel back to the uplink before I transmit.  I
>usually leave it set to the uplink channel, and try to remember to hit
>the A/B button before I change frequency.
>
>Just keep at it - after a few tries it becomes second nature.  You
>rotating the arrow to account for phasing differences and moving it -
>slowly - as you lose the audio becomes pretty automatic.

Tom and Wayne,

Well I sort of over embellish my comments for "effect" sometimes.  The
"wave" or "dance" as it is called up here refers to the motion used to
acquire the satellite at AOS.  If this were a rotator mounted antenna it
would be calibrated for pointing, but when hand held you only have a rough
idea of heading.  So the technique has evolved of moving the antenna in a
side-ways figure-8 and twisting the antenna back and forth thru 90 degrees
of polarization to find the satellite.  Once you hear it then it just takes
a small shift in positon and orientation to peak it up.  Experience
certainly helps the process of course.

What I noted was that after about 2 minutes I would lose the satellite for
some reason even though slowly keeping it peaked.  Some times I think it
was doppler or polarization shift, but maybe the other station dropped off
point.  Having the FT-817 programmed in five separate channels to
progressively move with doppler seems to work well.  UHF stepped in 10 KHz
while VHF stepped in 2.5 KHz.  This was just the factory suggested
sequence.  I am going to play with the steps to find the optimum size.  All
I have to do is change channel as the split frequency is pre-programmed for
each channel.  I can also just use the central channel and tune the
downlink with the vfo but this appears more clumbsy [the vfo knob is easily
knocked off freq. since the radio rests against my chest].  A quick channel
change takes only a seconds attention, then its back to keeping the antenna
pointed and operating.

I would only consider VOX since it is built into my radio.  A headset-boom
mic and VOX requires only to speak when I want to transmit.  No mic to pick
up and set down, or button to press.  So I would have one hand holding the
antenna and the other free to log.  I have to get the stuff to try it
out...only theory right now ;-)

Next operation will be from NJ or Michigan.

73, Ed

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