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[TenTec] Why Ethernet?

To: <tentec@contesting.com>
Subject: [TenTec] Why Ethernet?
From: kw0d@netexpress.net (Dave Kamp, KW0D)
Date: Mon Jun 2 11:01:28 2003
At 07:45 AM 06/02/2003 -0400, you wrote:
>Why would you want to spend the money of encoding packets at 10mb to 
>control a simple radio or rotor.  It is like putting a 500hp pump and a 
>fire hose into you glass of milk??  

I've got a boat like that... and it makes me smile every time I push the
throttle forward... I kinda like it!

>RS232 and USB among others are great 
>for what they are doing, and cost .033 or less.

There was a time when the hardware cost for any interface was about the
same.  Nowdays, Ethernet is actually cheaper- the magnetics, socket, and
chipset are so prevalent in volume (they're used in a whole lot more than
just interface cards), that there's no price advantage whatsoever.  As for
programming at the device end, it just doesn't take much-  even my aging
Omni VI has communications processes for address and data management.
Google for the "Packet Whacker"... PIC and ARM processors are extremely
powerful, and when coupled to a basic Ethernet chipset, do very nicely in
an interconnected world.  Cool part, is that anyone can walk down the aisle
at a hamfest and pick up a surplus 16-port Ethernet 10mb hub for under $20.

But to make myself clear-  I don't have anything against good-old-fashioned
RS-232- I've been using it for years.  My PK-88 TNC works nicely with it's
RS232 port, and I've been happy with it since day one.  I've never been
really excited about having only a few serial ports on a PC, nor have I
been thrilled by how much time I've wasted trying to make several USB
devices play well together.  I do have a box specifically set up to make my
TNC connect to my network, and although the solution is rather large, it's
back in the attic of a building 300' away, so I don't care.  It has an IP
address that I telnet to, and it's always on-the-air, no matter WHAT
machine I happen to be sitting before.

Here's an ethernet-flexibility concept to consider:

I've got a remote-base system here on a local 2m simplex frequency.  I've
got one radio (an Icom R-22S) hooked to an antenna atop my tallest tower.
Connected to the Mic and Speaker jacks of that radio is a remote-control
panel consisting of a funky transformer, two capacitors, and a relay.  From
that relay panel comes one twisted-pair, which (through one of my extra
runs of CAT5), is patched in a pair that can be found in the back building,
in my radio shack, in my workshop, in the kitchen, the office, down in the
basement, and way down in the boathouse.  In each place is a surplus
commercial DC remote-  got a few GE's, a Nova (the best!) and some
Motorolas.  Each have a speaker, mic, and PTT button, and from any of those
locations, I can hear radio activity, and I can talk.  Works great, 'cause
the radio and antenna are in optimal locations, and the operating panels
are in optimal locations.

It'd be really nice if I could do a couple'a more things...  
1) control squelch    --sometimes someone's just enough in the fringe...
and sometimes the QRN is high...
2) control frequency & shift  --sunday night nets are on other frequencies,
and I often have baby-duty...
3) add my 6m remote-base system  (Did I mention I've got a similar system
on 6m?)
4) add my Omni VI so I can rag-chew on 160...
5) spin the tribander
6) QRO??

Of course, this would take some substantial engineering and lots of
complexity, unless each radio just had an Ethernet port that carried
control and audio... then I'd just plug 'em into my switch and sit down at
one of my PCs...  

And last:
7) set up a server to automatically log transmission frequencies, times,
antenna selected, beam heading, SWR, and automatically order a pizza 4
hours into the contest?

8) with just one wire going from each device to a hub... no audio cables,
no mic cables, no PTT/TX cables... no RF-in-the-mic buggers...
---------------------------------------------------------
73's from KW0D Dave in LeClaire, Iowa
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