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VK3JMA > PACKET 30.04.04 07:23l 138 Lines 6103 Bytes #999 (0) @ WW
BID : A00034VK3JMA
Read: GUEST
Subj: Re: * 9k6 *
Path: DB0FHN<DB0FOR<DB0MRW<DB0WUE<DK0WUE<DB0RES<ON0AR<VK6HGR<VK3AYM<VK3DSE
Sent: 040429/0951Z @:VK3DSE.#MEL.VIC.AUS.OC #:11883 [Narre Warren] FBB7.00g25
From: VK3JMA@VK3DSE.#MEL.VIC.AUS.OC
To : PACKET@WW
Hello,
G6YFF wrote:-
> The Yaesu tranceivers that are 9k6 ready actually do work. I have an
> FT-8100 and an FT-847 and both work excellently at 9k6 using a PacComm
This 9k6 stuff all seems rather expensive and really not worth the
trouble. Why bother with all the money and trouble.
Why not form a group with your fellow packeteer's, other interested hams
or just your friends locally and build a real network! A TCP/IP network,
one that has it's lowest operating speed set to 1 Mbit/s (thats 1,000,000
bits per second) and cabable of 11 Mbits/s.
Forget 7plus and file size restrictions, send out the entire contents of
that HAM UTILITIES CD you made up all 400 MByte of it, better still, make
it available in the /pub directory of your very own FTP server that you
maintain youself and allow others to copy the whole iso image in one go.
Have a full duplex Video session from the comfort of your armchair with
others. Run a web server, email server (real email, not packet mail).
And best of all, do it all at RF, no need for any Land Lines, although
that to can add that degree of enjoyment to those so inclined!
How......
802.11b, 2.4 GHz wireless Lans.
Most major cities around have some sort of organization that is dedicated
to linking it's boundaries via RF data and high speed RF data at that.
Those who know me know I have already done these things I speak of, those
who dont, here is a brief summary.
VK3YY and myself have set up a 2.4 GHz wireless lan betwen us covering a
distance of 7.5 km and a speed of 2 Mbit/s. 5.5 and 11 where tried but
considering the terrain and other factors we deceided to wind it down to
the 2 Mbit level and this way we maintain a solid link through all weather
conditions.
Glenn runs a email server on his system and if the need arises we can send
others email when we are not there. Screen captures, huge, BMP screen
captures get send in a matter of seconds. FTP a 300 Mbyte iso image in
under 30 minutes, that 10 megabytes in 1 minute 167 Kbytes a second, or
for those 1200 bauders, 167000 cps, mmmmmm!!! (best we did in the early
days of the link was 600 Kbytes /second. that was at 11 Mbits/s but as
already stated that did not prove efficeint)
Email attachments.....no real limit, time and server configurations that
is about it! Gleens server does not like really hugh attachments, ie 10
Mbyte, so thats easy fixed. Outlook express lets you locally split up a
file to a predefined size (2 Mbyte here) and thens send them all as
seperate files only to have Outlook express at the other end, combine them
back into their HUGH size! I have sent a 47 Mbyte file successfully, in
only a few minutes.
Using netmeeting we can hold a 2 way web cam qso with audio.
Share an internet connection, yeah, well we dont. We both have our
respective internet services and treat them privately but that does not
prevert you and a few friends with sharing it, even adsl/cable is easy!
How is this done.....
We both use "Access Points" (AP). These are just what the name says they
are, Wireless LAN Access points. They act similar to a HUB and pass data
to and from the RF side to the LAN to the computer. 1 AP is in AP mode
(like host/server/master call it what you like it's the boss of the
system) the other is in AP-Client mode (slave/client/subbordanite).
Many AP-Clients can access a AP at once and as such an AP can act as a
"roundabout" to the RF network allowing a AP-Client to link to another
AP-client, like a hub! Naturally as we know from our packet activities,
to many users can serverily hamper the operation of the network, this is
true for LAN's and Wireless Lans. As with packet, you can use 2 or more
AP's on differeing channels and antenna orientations allowing a reduction
in network congestion. Basically, WLANning can mirror how our packet
network works but at such higher speeds!!!
Equipument.....
As has been said, AP's in one mode or the other as the basis of a system.
Powers levels are *very low*. I run 17 dbm (80 odd mW),but in order to
preserve as much of the power as possible both Glenn and myself run our
AP's at the back of 24dbi parabolic grid antenna's greatly reducing the
losses due to cable run's and connectors. Amps are available from 250 mW
to many watts (and many $$$) but local regulations may prevent you from
actually using these power levels???? Either way. Good installation
practices and good quality products will assist you in making sure you get
the most out of your system.
Naturally, rule of thumb at these frequencies is that the path HAS to be
Line Of Sight (LoS) but both glenn and I have large gum trees in the near
path which do not help but also do not make a big difference (maybe these
are the reason for poor 5.5 & 11 Mbit/s usage???? Maybe a chain saw to
the neighbours trees????? Nah, to nasty).
If you happen to have a group of interested people that DO NOT have LoS to
all then maybe you can set up a remote AP on a favouriable location as a
distrubution point, aka NODE (repeater etc). We have actually obtained
permission to set up just this on a high sited factory. This will open up
our network to approximately 4 other hams in a 5 to 6 KM radius of the
site. There are probally other interested parties but we do not know them
yet.
Cost....
Whatever you can get equipment for. AP's range from low $AUD80 to several
hundred $AUD. Amps $AUD300 +, depending on make & watts. Antenna, knock
on the door of some one who has an old ex Paytv MDS array (Australia only,
MDS not used in all states anymore), big ones generally 24 dbi, mid 18dbi,
small around 14 dbi.
So in summary, not bagging 1200/2400/4800/9600/etc packet operation, just
please be aware of other ways of enjoying teh great hobby of Amateur
radio.
Have a look at www.melbourne.wireless.org.au or similar sites suiting your
local area.
All the best
Mark
Node GXT (melb wireless)
----------------------------------------
73 - Mark, VK3JMA @ VK3DSE
Message sent via Winpack v6.80 and
Telnet on a 2.4 GHz Wireless Lan.
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