From: Stephan Greene <sgreene@access.digex.net>
Newsgroups: rec.radio.amateur.space
Subject: Re: What sat can reach with 144/440 FM radio?
Date: 2 Jun 1995 16:53:03 GMT
Organization: Me, Myself, & I
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durham@lobby.ti.com (ken) wrote:
>In article <74387@ve2noq.ampr.org>, ve2yag@ve2noq.ampr.ORG says:
>>
>I have heard AO-27 are open weekend for cross-repeater 144->440
>>but I never heard it. Can you help me?
>>
>Sorry to bring bad news, but unless AO-27 changes management the schedule
>of operation is erratic at best. It was turned on for the weekends (daylight hours) before
>the present management took over, but now is on at random.
>

Another possibility is that your rig can't hear the satellite.  When it's 
on, it is usually running ~1/2 watt.  My Standard dual-bander can barely 
hear it around the best part of a good pass, and that is with the squeclh 
off and I know what to listen for and where and when to listen.

Adding a low noise UHF GaAsFET preamp works wonders and makes the 
satellite copyable and usable for much of a pass, even mobile in motion. 
 Alternatively or in addition, a small (4-6 element) yagi can be 
hand-held and pointed in the general direction of the satellite.  Wave it 
around for best signal reception (azimuth, elevation, *and* 
polarization).

Downlink center freq is 436.8 MHz, plus/minus doppler.

>There are no other FM birds up and unless there are some plans in the 
>works, there will be none in the next few years.  P3D does not have any
>provision for FM (although with some careful planning it would have been 
>possible.) Other planned satellites are all digital store and forward or
>special interest experimental (semi-commercial.)

Mir and SAREX can be worked with the 2M portion of the radio.  If the
radio is 9600-baud ready or modifiable, it may be usable on the 9600 baud
satellites.  My Standard dualbander is 9600 baud ready.  It receives
the UO-22, KO-23, and KO-25 birds well (filter skirts seem wide enough so 
5kHz tuning steps are not fatal) when used with a preamp and omni 
antenna.  I had limited success with the stock radio on uplinks, and 
suspect either distortions in the TX side (see the recent QST reviews and 
QEX articles on subject) or misadjusted radio/TNC TX gain levels.


73
Steve Greene  KA1LM
ka1lm@amsat.org