[aprssig] PC's vs stand alone TNC's (was: no subject)
A.J. Farmer (AJ3U)
ajfarmer at spenet.com
Sun Feb 20 20:45:00 CST 2005
>So here is what I need...a box no larger than a MFJ1270C (and smaller
>would be much better), and which can be expected to run night and day
>for 5 years without a visit and operate in temperature extreems.. And
>remotely programmable..my furthest digi must be reached by digi'ing thru
>3 intermediate digi's.
It's in the works. ;-)
A.J. Farmer, AJ3U
From: aprssig-bounces at lists.tapr.org [mailto:aprssig-bounces at lists.tapr.org]
On Behalf Of Ron Stordahl
Sent: Sunday, February 20, 2005 12:21 PM
To: TAPR APRS Mailing List
Subject: [aprssig] PC's vs stand alone TNC's (was: no subject)
I agree completely that something new and better would be desirable.
But consider the constraints under which I, and I believe many others
work: Limited access sites, some at significant distances. My sites
range from one locally to one 220 miles away. On the average a 2 hour
drive to get to one. And in the winter many of them are essentially
inaccessible, unless you have a pile of money on hand and can hire
equipment to plow the way. They are all commercial sites where we are
'non-paying' guests. Of course the owner will plow the way if their
equipment fails, but we wouldn't even consider asking for such help. We
are just lucky to have the sites and as such we don't ask for a single
favor. If we visited them too often we would stand the chance of
loosing them. Space is limited and the owners are concerned also about
safety and security. One of our easily accessible sites is on top of a
240 foot grain elevator. If we were to install anything up there with a
fan in it we would get booted (our equipment is completely silent which
works to our benefit), and can you imagine what the inside of such a
piece of equipment would look like after 6 months? You probably
couldn't even see the components for all the dust. Did I mention rats
and insects...I guess I didn't. Only a couple of our radio tower sites
have modern climate controlled 'shacks' at the bottom.
And we are cheap! Our equipment typically consists of old Motorola
Micor mobiles (which I think would survive an atomic blast) and
MFJ1270B's and C' (yes I can hear the laughing right now...but some of
these have run using the prior software, TheNet, in dxcluster service,
for 10 years without a single failure). It was a multi year project to
get all of them converted over to 144.39 and UIDIGI. The power
supplies, if we share with a voice repeater we have been able to use an
existing power supply, if we are alone we use surplus magneto resonant
(i.e. non electronic) supplies, not one of which has failed in 10
years. The only radio failure we had among 15 radios was when one of
the Micors had a relay failure and went key down for 3 days at full
power before we were able to reach it. Didn't even hurt the radio!
If I had to visit each of our sites even once per year I would have to
throw in the towel, it would take too much of my time.
Marco Savengnago, IW3FQG, the author of UIDIGI, which is what we run at
all our remote sites, has recently expressed interest in updating his
code to support the 'new paradigm'. I do not know if or when this will
happen, although I am hopeful. I do not like being at the mercy of one
person, no mater how generous he is, as his time is limited, he may
loose interest, etc. The same goes for Kantronics, when are they going
to release new code for us? So I would very much like a new open
So here is what I need...a box no larger than a MFJ1270C (and smaller
would be much better), and which can be expected to run night and day
for 5 years without a visit and operate in temperature extreems.. And
remotely programmable..my furthest digi must be reached by digi'ing thru
3 intermediate digi's.
Oh, did I say for less than $100.00? That is what we have right now,
picking up the TNC's used on eBay and at hamfests, as I have been doing
So that is what we need, when it becomes available, we will replace our
existing equipment, when it fails or when we can afford to do so. In
the mean time we will continue to provide service with less than modern
(but highly reliable) equipment.
So that you don't get the impression that I am stuck in the past, I will
add that at our central site, just 200 feet from me, in a nice clean
environmentally controlled location, I run Windows 2000 with UIView32
and AR-Cluster and have a T1 connection. It works well but is entirely
unsuited for my remote sites.
I would be very happy with something new that could meet our
requirements and constraints. Please come up with it, and soon!
Henk de Groot wrote:
> Ron Stordahl schreef:
>> Do you really think for one minute that it would be wise to put a PC
>> at a remote site that runs 40 F below in the winter and 100 F above
>> in the summer and is subject to regular power failure/restores?
>> If so, come here and take over the maintenance of 15 remote sites
> Why it is possible in Italy, France, Germany, Belgium, The
> Netherlands? Why should a PC board be less reliable than a KPC-3? I'm
> talking about a solid system, without a spinning harddisk, I bet the
> components are not any different than the components used on a KPC-3
> and in your TRX.
> Let met ask you straight, did you ever try it? How do you know a PC
> will not work under these conditions when a Kantronics TNC and your
> commercial-grade TRX seems to work?
> Besides that, I never said you shall have a PC. A PC is currently the
> only solution available, but if we make a decision today to move into
> a new and better direction then even solutions for sites like you
> mention will emerge. Note that we are only discussing this right now
> and already people show up with *great* ideas like a PIC controller to
> take over the digipeating function and replacing the KPC-3 PROM with
> something like a UIDIGI type of PROM.
> I don't understand the tendency to pick the exceptions to show why
> something can't be done. Lets look at the opportunities, solutions for
> the exceptions will then emerge in due time, people are creative and
> always found ways to overcome problems.
> Kind regards,
> aprssig mailing list
> aprssig at lists.tapr.org
aprssig mailing list
aprssig at lists.tapr.org
More information about the aprssig