You could also put up a simple digipeater/node for packet for either 1200
baud or 9600 baud. If the enclosure is built correctly for the
conditions, they can be pretty secure and reliable. I have read about a
group who put up a sloar-powered node on a snow-capped mountain in Alaska.
There is about a 2 week window each year that they CAN get to the
mountain, and that still requires snow shoes! (The timeframe is in
mid-july). The node has been in reliable operation for several years now.
It is the villages' only reliable digital link with the outside world. It
can be done.
Since your location will probably be much more hospitable, you shouldn't
have a problem. Depending on the amount of data you wish to exchange, and
the speed you whish to do it, you could run either 1200 baud or 9600
(assuming its legal in your country). If you do place it on the top of
the mentioned mountain, it would provide coverage for much more than just
your immediate need.
On Wed, 20 Jan 1999, Riley Williams wrote:
> Hi Damian.
>
> > This is very interesting, beacuse I have a similar problem that I
> > need to solve in Indonesia - we should pool our resources!
>
> > We are working on a rain-forest project on the Island of Seram -
> > help local people protect their rare and endangored bird species by
> > encouraging bird-watching type tourism.
>
> > Anyway the village where we are operating is about 150km away from
> > the nearest town with phone connections and there is a 3000m
> > mountain in the way. I have been working with a local ham radio
> > operator there to try and get his setup going (his radio died about
> > a year ago).
>
> If my memory's correct, 3,000 metres is around 10,000 feet, which
> makes it considerably higher than anything in the UK...that's about a
> third the height of Mount Everest, the highest in the world...
>
> > What we have decided to do, is have a computer in the nearest town
> > running Linux which will dial up the local ISP and upload and
> > download any email. Then another computer in the village will,
> > using the radio link, contact the one in the town and pick up the
> > email from there.
>
> The first and most important question has to be whether doing so would
> be compatible with the said ham's licence, but I would presume that's
> already been checked...
>
> > On asking around, I have come up with two suggestions as to how to
> > get the radio link to work:-
>
> > 1) Use VHF frequencies (e.g. 2m band) and put a passive repeater
> > (two yagi antennas connected together) up on this high mountain.
> > However we are not sure this will work due to the abundance of
> > vegetation (not to mention the three day jungle bash to get to
> > the top). Then using AX.25 to transfer the signal between the
> > computers.
>
> I would tend to suspect that a PASSIVE repeater won't work in those
> conditions, although I can't say for certain. However, an ACTIVE
> repeater powered by solar cells could probably be made to work fairly
> simply...
>
> Also, at 10,000 feet, there shouldn't be much in the way of vegetation
> anyway, although cold and wind could both be serious problems. I don't
> have the details to hand, but memory says that a Scottish Munro is a
> mountain over 3,000 feet high. I remember climbing Ben Venue, which is
> NOT classed as a Munro, and noting how bleak and windswept it was at
> the top, so I find it hard to believe that a mountain probably four
> times as high could be much better...and that's even allowing that
> you're much nearer the equator where you are...
>
> > 2) Use an HF radio and then use the PACTOR protocol. This has been
> > very successfuly used in Africa before, however the equipment
> > seems to be quite expensive (around US$3000 for each station -
> > we would have to get two), so *may* be out of our budget.
>
> I know nothing about PACTOR other than that all the units I've seen
> for it are expensive, so can't comment thereon...
>
> > I am trying to think of a way to start off with a cheaper system
> > and slowly improve it rather than having to do a big outlay at the
> > beginning. I am also concerned about buying a lot of gear and then
> > finding out a month later when we finally get it to Seram, that it
> > doesn't work due to some local radio wierdness.
>
> A few fairly obvious questions:
>
> 1. If you go with the idea of a repeater of any form on the said
> mountain, how secure is it likely to be?
>
> 2. Could such a repeater serve other communities as well as the
> intended one? In this context, it may be worth considering
> mountains other than the one on the direct path.
>
> Personally, I would tend to suspect that an amateur band repeater
> located at 10,000 feet above sea level would cover a far larger area
> than just the island and village you refer to, and there would thus be
> far more to offer than you appear to be considering...
>
> > Any information you come up with would be extremely helpful.
>
> Hopefully the above helps...
>
> Best wishes from Riley GM7GOD / KB8PPG
>
> ---
> * ftp://ftp.MemAlpha.cx/pub/rhw/Linux
> * http://www.MemAlpha.cx/~rhw/kernel.versions.html
>
>
-----
Jim Kusznir ([EMAIL PROTECTED])
RidgeNET Tech Support
371-3501
[EMAIL PROTECTED]
