[aprssig] APRS via satellite

[Robert Bruninga]

>>> whiskey7doa at gmail.com 10/12/05 12:01 PM >>>
>    I have a lot of questions about APRS via satellite.

See http://www.ew.usna.edu/~bruninga/astars.html

>1. I am running a D700 mobile and am wondering about 
>[my] ...vertical... dual band antenna. 

Its perfect.  Even better if it is a lower gain one becuase
they have more energy above the horizon.

> Do you have to have a special antenna to communicate 
>through a satellite?

Most satellites except for ISS have weak downlinks and
you need gain antennas to hear them when they are low
(most of the time).  THey do pass over pretty high
(meaning close to y ou) about twice a day so even a 
low gain antenna will hear them on those passes.

>2. What is the best way to pick the "bird" you 
>want to use? It seems there are several...

For APRS, there are only two (maybe 3)
- ISS digipeater is best TX on 145.99, RX on 145.8
- PCSAT2 TX on 145.825 RX (with beam on 435.275)
- PCsat is basically dead except for near mid-day passes
  over the northern hemisphere
- ECHO has not been enabled for digipeating yet.

de WB4APR, Bob