Hi John
Your reply is very useful info for me.
It doesn't surprise me that your PSKMail server has very few users. As you
say, many mariners have satphones or Iridium phones etc.
But it does mean that if I set up a PSKMail server in Phuket, the purpose of
this is not really to provide daily HF email comms for mariners in the Indian
Ocean.
So I don't really need to commit a dedicated transceiver to this service.
Rather, especially with my location in south-east Asia, I would see my server
as providing an HF email service for the occasional sailor, but more as a
'gateway' to email/internet in times of natural disasters in Asia.
As the recent earthquake in Nepal demonstrates, there are regular and severe
natural disasters in Asia, which can overload/knock out mobile phone, landline
and internet services. (Of course, this happened right on my own doorstep with
the 2004 tsunami).
So my server would be ideally located to provide HF email/internet throughout
the major south-east Asia zone, from India to the Philippines, Nepal down to
Indonesia.
I don't want to go down the Winlink Pactor 4 path, because it is highly
unlikely that radio hams or NGOs in these developing countries would have a
Pactor modem. And I'm not going to spend $1,000 to buy a modem at my end, just
in case someone wants to connect to it!
My role in Phuket is as a Tourist Police Officer, responsible for assisting the
many (MANY!) foreign tourists if a local disaster occurs. So that role fits in
well with me having a PSKMail server and HF-email capabilities.
So... I understand that my server may not have much traffic, but that it would
be very useful if a disaster occurs in south/south-east Asia.
I will get this all set up, test out the coverage for the selected bands, and
then also make sure that the ham communities in these countries (eg Nepal,
Bangladesh etc) know about my server, so that are able to use it (either day to
day or after a disaster occurs).
Simon
--------------------------------------------
On Sat, 30/5/15, John Douyere <vk2eta@xxxxxxxxx> wrote:
Subject: [pskmail] Re: Server in Asia - 30mb antenna question
To: "Unname" <pskmail@xxxxxxxxxxxxx>
Received: Saturday, 30 May, 2015, 1:37 AM
Hello
Simon,
I do not get many
connections through my server. I am the main user when
4WDriving in the Australian bush in places where there is no
mobile coverage. There are a couple of other users also land
based.
But that is
possibly due to the frequencies I normally scan (80, 40 and
30M) so it does not have a large foot print.
I only changed the scan to 30, 17
and 15M for a few months when I when to Cape York up North
two years ago.
I
have had only a few requests from maritime mobile from New
Caledonia and New Zealand that were interested in the
server.
But of course
each region is different.
I suspect that these days if you are
on the high seas a sat phone is a better and more reliable
alternative and not that expensive anymore. So the need for
HF radio links is definitely reducing from what I see.
Sailmail has closed now, and having used Australian based
Winlink servers in the past I didn't hear a lot of
traffic on them either. Just my personal
observation.
I also
have a dedicated FT-857 as the server, set at 50W max and
that has been working reliably for several years
now.
All the best,
73, John
On Fri, May 29, 2015 at
3:23 PM, Simon Luttrell <dmarc-noreply@xxxxxxxxxxxxx>
wrote:
Hi John -
thanks very much for your very useful comments!
I can agree with you about propagation at my latitudes.
The band that seems to provide the best propagation for me
is 15 metres, using my DX Engineering 80/40 Thunderbolt
vertical antenna, that is resonant on 7MHz (so I'm using
it on its 3rd harmonic, with very low SWR). So even though I
am not using an antenna designed for 15 meters, I am getting
good coverage.
I have tested my vertical antenna on 30 metres, but the take
off angle is too low ==> I'm heard on the other side
of the world as a weak DX signal, but the first skip zone is
the area that I really want to cover, ie the Indian Ocean
etc.
I am waiting on a 30mb collinear wire antenna to arrive,
which I'll test at a lowish height to see if it will
perform as a NVIS antenna, (but 10MHz is a bit high for
NVIS).
I have to say that I've been monitoring 10.148MHz for
days, but receive no PSKMail server beacon signals
whatsoever :(
I will dedicate a server and Yaesu FT857 rig to this
service. So I want to ensure that my expense on these
items is not 'wasted' because no-one can use my
server. If it can provide good coverage west over the
Indian Ocean for mariners, and over south-east Asia for
landbased/emcomm/NGO etc etc, then that will meet my
aims.
I think the best that I can do is to set up server and rig,
and then do some tests on different bands at different
times. Maybe I operate on 15mb during the day and possibly
on 40mb at night.
I will check out the propagation links you provided to help
me in my decisions.
Simon
PS - How 'popular' is your server? How many
emails/connections do you typically have per day/week??
--------------------------------------------
On Thu, 28/5/15, John Douyere
<vk2eta@xxxxxxxxx>
wrote:
Subject: [pskmail] Re: Server in Asia - 30mb antenna
question
To: "Unname" <pskmail@xxxxxxxxxxxxx>
Received: Thursday, 28 May, 2015, 9:56 PM
Hello
Simon,
That's a great
idea, and totally feasible in my opinion.
Some feedback based on my tests here
in Sydney that may be useful for your
installation.
I found
that 30M in the lower latitudes has a limited reach
during
most of the time. I got reliable links back to my server
on
30M up to about 1500KM.
I tested my server all the way to
the tip of Cape York in north east Australia which is
located at -12 degrees latitude (similar to Phuket at
+9
degrees) and I could get back to my server in Sydney
(approx
2500KM strait line) reliably only on 15M and sometimes
on
20M.
So based on your
objectives I would advise to consider scanning a few
frequencies rather than just 30M. I would propose
scanning
30M, 20M, 17M and 15M. Maybe with two consecutive minutes
on
30M to make up the 5 minutes scanning cycle.
Now my base antenna may be a
contributor to the limited reach of the 30M band as it is
an
inverted V at 12M above ground level with an autotuner.
But
I suspect it is not the main factor as it seems that in
Europe they get reliable 30M links up to that distance
even
with vertical antennas. And they are at a much higher
latitude where lower frequencies work a longer distances
in
average.
If you look at the example below of
the prediction chart for 11:30AM local time in Phuket
(the
chart is centered on Brunei but the latitude is similar
at
about 4 degrees North) you will see that to get a good
coverage of the indian ocean you need to go up to 24Mhz,
but
my guess is that even if you stop at 21Mhz you will get
decent DX capability.
If you want to run propagation
simulations, the Australian IPS services provide some
interesting tools (see http://www.ips.gov.au/HF_Systems/6/6/2
and select Brunei Bay Radio for example).
Hope this helps,
73, John
On Thu, May 28, 2015 at
6:24 PM, Simon Luttrell <dmarc-noreply@xxxxxxxxxxxxx>
wrote:
Since
there seem to be no PSKMail servers in Asia, I am
thinking
of setting up a server from my QTH on the island of
Phuket,
south Thailand. This should provide coverage over the
Indian Ocean and southeast Asia land masses.
I have a first question. For the PSKMail servers that
already operate on 30mb, what antennas are you guys
using?
I'm sure that I will have more questions, but this is
an
important one to see if my idea is feasible.
Simon
