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

RE: Made my first contact!!!!!!

Congratulations on your first QSOs, Stephen!

> receiving on 435.300 My radio only tunes in 5 khz steps, how should I
> compensate for doppler shift? Do I need to be as concerned 
> with it on the
> uplink as I do the downlink? Should I start tuning above or 
> below the center
> frequency to compensate?

There is a great little article on the AMSAT Web site at the following link:


It describes the process, but in a nutshell you probably don't have to
fiddle with your uplink frequency at all because Doppler is less of an issue
on VHF.  For my downlink, I usually start 10 KHz high at the beginning of
the pass (435.310) and drop to 10 KHz low at the end of the pass (435.290).

I have five pairs programmed into my HT.


I just cycle through the pairs to find the one that is the clearest on
downlink.  On a "glancing pass" where the bird remains several hundred miles
downrange and never goes overhead, you may find you only need the middle
three pairs, because the doppler shift is not as much since the satellite is
never coming right at you, or moving directly away.

Good luck!


Brent Taylor, VE1JH
Doaktown, NB  FN66
6M VUCC #418, AMSAT #33576 
Sent via amsat-bb@amsat.org. Opinions expressed are those of the author.
Not an AMSAT member? Join now to support the amateur satellite program!
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org