I'm writing back again with a few more details I've found.
On 2011-04-28 20:49, Joseph Apuzzo wrote:
As some of you know I WAS a ham ( KD4HLC look it up ) and back in the
early 90's (1992-3) mucked around with a 2400 baud Packet Radio ( on 2m
/ 70 cm )
Well that was almost 20 years ago and it seems that nothing has
happened? packet radio is still around 2400 to 9600 baud?
Turns out things have changed a tad. 1200 baud AFSK seems to be the
standard on 2m, but faster rates and FSK seem to be being used at 70cm
and above; 9600 baud is apparently typical on 70cm. Apparently radios
typically need modification to be able to do faster data transfers.
http://www.symek.com/g/pacmod.html
Can anyone help me re-connect with my roots?
1) What is the modern hardware?
There are apparently some USB-based packet radio modems available.
Looking through the "hamradio" section in the Debian tree comes up with
"baycomusb" which are drivers for the "HB9JNX packet radio usb modem".
> That is what is the current "high speed" data transmission also on
> what frequencies?
2) What are the distances between nodes on the mesh? I know that
frequency determines that, but hay my mind is not what it use to be some
20 years ago.
3) Are there any really cool DYI modems that pair up with Linux BBS like
software? Like
http://dangerousprototypes.com/2011/01/31/packet-radio-and-the-arduino-radio-shield/
Here's where it gets interesting. Today's computers are fast and they
all come with sound cards, all of which are capable of outputting an
alternating 1200 Hz and 2200 Hz tones for AFSK. So... now you either
have a choice of getting a TNC, or using the sound card directly in
Linux to ACT like a TNC, and making a small circuit to activate the PTT
(Push-To-Talk) on the radio -- i.e. the transmit button -- when sound is
coming out.
http://www.qbjnet.com/packet.html
So you have your choice of buying a TNC, building one, or doing a
software-based TNC using the sound card.
3b) What is APRS? It sounds cool, but what's the down low? ( aka is it
cool enough for me to want to get my ticket back? )
I haven't investigated this more yet, but I did find an "aprsd" Debian
package which might be worth looking at. Once installed I bet
/usr/share/doc/aprsd/ may have some instructions and links to follow.
--
-- Chris
--
Chris Knadle
[email protected]
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