Packet Radio (was:Re: Modem tones over television or radio)

From: Computer Room Internet Cafe <netcafe_at_pirie.mtx.net.au>
Date: Fri Dec 18 07:13:59 1998

-----Original Message-----
From: Marvin <marvin_at_rain.org>
To: Discussion re-collecting of classic computers
<classiccmp_at_u.washington.edu>
Date: Friday, 18 December 1998 17:41
Subject: Re: Packet Radio (was:Re: Modem tones over television or radio)

>What you are looking for is called a TNC (Terminal Node Controller.) And
>surprise, surprise, this is all on topic as I have several TNCs designed
for
>the C-64 (no, I'm not interested in getting rid of them.) Years ago, I
sold
>a friend of mine an IBM PC (yes, PC) with two floppy drives that he used up
>to last year to monitor packet radio here in Santa Barbara. There is also
a
>device/software IIRC called Baycom that can be connected to the serial or
>parallel port and will work for packet radio.

I have a Baycom modem that I made by converting a Sendata C64 Dumb modem.
(Hey, that makes this msg on topic even, it dates from about 1983!)
Basically, it works with driver software, either eprom based in the 64,
(can't think of
the name offhand) or device drivers and and a terminal, on a pc. Provided
the
PC was quick enough, (an XT will do for the genuine Baycom software)
the effect is that it emulates a tnc at a fraction of the cost, significant,
since tnc
manufacturers are the biggest thieves out IMHO, charging $300 for the
equivalent
of a 1200 baud half duplex modem, with very simple firmware.
There are now several different drivers for baycom modems, including some
for
Windows and Win95, which was always a no-no because of interrupt latency,
but the
new machines are so quick that it's not a big factor at 1200 anymore.
Linux also has native support for both AX25 packet and Baycom modems.
I still use my converted C64 modem on 2M packet, though it now talks to a
P100
running Win95 rather than the original XT with Dos 3.3

>I might add you also need a radio to monitor packet radio :)
>and a ham license to utilize it.

I have seen packet activity in Sydney (some years ago now) on the 476mhz
CB Band. It's illegal to do it there of course, but I have never heard
of anyone being prosecuted for it either. It is still going on in some
places.
I have heard there is some activity using 300baud packet, AMTOR and RTTY
on the 27Mhz CB band as well, though I've not heard it myself.

Cheers
Geoff Roberts
VK5KDR
Computer Room Internet Cafe
Port Pirie
South Australia.
netcafe_at_pirie.mtx.net.au
Received on Fri Dec 18 1998 - 07:13:59 GMT