[aprssig] Need help testing 30m HF APRS in the Northwest

[Ben Jackson]

On Sun, Jul 30, 2006 at 09:18:11PM -0400, Stephen H. Smith wrote:
> 
> The actual mark and space frequencies for 30M HF APRS are 10.149.2 and 
> 10.149.4 .

Yes, I'm doing direct FSK at 10.149.200 and 10.149.400.

> Because of the very narrow receive passband of most TNCs 
> on 200 Hz shift on HF,  you MUST be within 10-20 Hz absolute of the 
> correct frequency on transmit.

Well, the transmitter and receiver have to agree within about 20Hz.
How do HF gates generally maintain that <2ppm accuracy?

It may be that a mobile HF APRS beacon is impractical.  If so, I'm
learning it the hard way.

-- 
Ben Jackson AD7GD
<ben at ben.com>
http://www.ben.com/