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[STENSAT] Spurious signals vs. STENSAT



    Once again I was able to hear some signal returning from Stensat. One 
    must be very careful to be sure spurious signals are not confusing the 
    issue. First, be sure that there is no signals when the bird leaves and 
    try and find some sign of doppler. Do use a multimode rig if at all 
    possible! FM only rigs are rather difficult. Cliff K7RR 

In my past posting, i reported such problems with my Alinco HT.  Alas,
the Yaesu 736R exhibited the same spurious signals this morning that i
observed Saturday night.  Unlike my first observation, it did not show
doppler nor disappear after end of pass.  I did hear a couple of 9k6
packet bursts during a couple of brief stops at 437.100 +/- (but nothing
heard during comparable visits to the JAWSAT frequencies).

Now, i am using a Larsen 2m/70cm diplexer, since my antenna is a dual-band
antenna (approx. 50 direct feed in both bands), and the same design was
used with both rigs.  I'm not convinced that these 'spurs', which show
up for me at 436.633, would show up with an antenna which has separate 
feeds for each band, such as an Arrow, or an AO-10 class antenna system.
I would be interested in hearing if anyone has observed the same 'spurs',
so i can find it if it might be related to my antenna design.

My conclusion now is that i did not hear my own downlink on during the
first pass i monitored soon after release, because, given doppler in
effect for the brief period i heard the downlink, would correspond to
where the fixed frequency where i hear the spurious signal.

So my conclusion for this last pass (UTC):

  14Feb00  14:10:31 14:18:00 14:25:30  00:15:00  160  74 347  80.7* JAWSAT

(or 06:18 PST MEL) is 'nothing heard'.

			       -- KD6PAG
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