[Date Prev][Date Next][Thread Prev][Thread Next] - [Date Index][Thread Index][Author Index]

Re: "Precision" Antenna Pointing





On Tue, 09 Jan 2001 16:05:02 -0500 Bill Hurlock <bill@hurlock.net>
writes:
> All discussions concerning beam pointing don't really seem to be that
> important in that most of the antennas we are using fall well 
> outside the 1 to 3 degree beam width areas. The rotors are not that 
accurate 
> either. The Bar-B-Q antenna from Myers I use is only in the 13 to 14
degree 
> range. I can rock the AZ EL a fair amount before I loose signal on AO40
S beacon. 


 Hmm, I quickly as possible rock the switch on my G5400b and I get a very
noticeable drop in signal a couple of s units on my 847, with Mayer
grill. If I rock it back up signal comes right back up. I bought my Mayer
at a hamfest,without any paperwork, so I'm not really up on it's
beamwidth, gain etc.   
  Another thing I'm noticing while collecting S band telemetry from AO-40
is that one day I can let my auto tracking system do the antenna pointing
for me, Next day it is off by about 8/10 degrees! Same program, keps,
computer, time wwv corrected before pass. This I don't understand. It's
like the orbit is predicted better one day, then the next, or in a
different part of the pass. This  happen's  about  1/2 the time I have to
manual track the bird. Of course I'm tuning the frequency by hand. I
could also do that automatically on 2m, but not s band.
   When I mentioned Antenna system, I mean Antennas, rotor,  tracking
computer,  and software. The whole system.

73 Jeff kb2wqm
----
Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org



AMSAT Top AMSAT Home