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WorldRecordWIFILink [1]
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Please add you interest, ideas and capabilities below for a MW
attempt at a world record wifi link.
TonyLangdon [2] (VK3JED) can provide
* 12V 55Ah SLA battery
* 150W 240V AC inverter
* P2 266 laptop running Fedora Core 3, capable of running off
battery above
* P3 1GHz laptop running Windows XP Pro
* HF and UHF CB for liaison
* HF/VHF/UHF amateur gear for liaison
* VHF "sniffer" for direction finding
* Magnetic compass
* Transport for up to 4 people and some gear (except large antennas)
from western suburbs
AdrianLodders [3]:
* 400VA UPS
* 1x 24Dbi ex galaxy, 1x (I think 15 or 18dbi) modded hills
* 8 slot 180 degree waveguide
* 3x CB radios (1 uniden and 2 generic)
* A good few meters of CFD200
MikeCampion [4] (node hkf)
* P4 laptop runing fedore core 3, hostap, kismet and 12v adapter
* Veritech 200mw pcmcia wireless card and pigtails
* LMR 400 cable
* UHF hand held cb's
* GPS
* 4wd and trailer
Jamie Moir from Techtopia
* Senao NL2511 CD Plus EXT2 200mW cards
* Pigtails
* 1, perhaps 2, 1.2m diameter/28dBi grids for 2.4GHz, but may need a
freight account.
HoracePinker [5]
* 2.8 metre sat dish (aluminium mesh type, formerly c band i belive)
mounting bracket is damaged at the moment ,wont take much to fix, and
it doesnt have a mast/stand.(but it is portable if youre willing to
wait 30 mins to assemble and dissasemble) It also would need a feed.
* 200mW veritech card plus one pigtail (poor quality but does the
job
* If I am Present I can bring a laptop with hostap/kismet runing of
cdrom
* 150mW Powerinverter and extension lead to power laptop etc from
12v battery.
David Smith
* 2.4 GHz amateur SSB gear to help with dish alignment
* (possibly) amateur microwave portable dish setups (TBC)
CRC
* 900W 240v generator.
* Lots of 2 way equipment for co-ordination.
DanFlett [6]
* 3 x 15 metre lengths of LMR400
* Pigtails
* 2 x 25dB Hills grid parabolic antennas
Peter melb_ap [7]
* 1 x 1.8 Mtr Solid Dish with stand (easy to transport)
* ready made & tested cantennas for feeds if required
* 1 x longreach amp for rx gain if required
* 3kva Generator
* 200w 12v pure sine wave inverter
* gps & mag compass
* 2.5Mtr grid pack dish antenna (ex commercial)
need a feed overflow: auto; border: 1px solid; padding: 3px;">
Adrian Lodders
Tony Langdon (Preferred site, most convenient, local knowledge)
Peter melb_ap [10]
Team B (Mt Buffalo)
Tony Langdon (Can go here if too many people at Camels Hump and not
enough here)
Mike Campion
David Nuttall
Stage 1 local metro equipment testing discussion.
5/8/05 Peter melb_ap [11] Myself and John bigjohn [12] have done
some initial testing of a 1.8mtr solid dish to see what comparitive
results could be derived on wlan and 2.4gig.
We compared the side by side received signal from node HKR between a
hills vagi (which is rated at 16.5Dbi) to the dish using a veritech
card and netstumbler.
The feed we used on the dish is a cantenna made from a corinthian
tin.
(netstumbler link to follow) The test put the dish at about 15db
better than the vagi in netstumbler Making it approximately 31db at
2.4 gig.
Comparitivly with the same cantenna on a 65cm offset dish in previous
tests showed about 28-29 db gain.
I dont know if the feed is quite right for the dish, but this was
just a rough test that i'd been planning anyway and thought i'd share.
Futher from this I want to see what the real world diversity
capabilities are of the veritech card.
Requirements Discussions
Antenna Discussions
- what feed design we could use
- what dish we'd use and where we could source a pair from
Peter melb_ap [13] 17-8-05 - from 12/8/05 mw meeting DN ratbaggy
[14], MC mjc [15], Peter melb_ap [16] ; regarding the feed, we
resolved to start testing commercialy made units
to attempt to bypass the r for dishes , david mentioned melbourne
satellites had a special on 2.5 ish mtr solid dishs for $150 as a
possibility (But i think we'll need much bigger for a legal eirp
record with diversity)
dna 19-8-05 Thinking about the beamwidth of the transmitting antenna.
At the distance we are talking about an antena with a beam width of 7
degrees covers something like 25 Km.
* convert degrees to mils (7* 6400 / 360 ) = 124.444
* 1 mil subtends 1 metre at 1 Km, so at 200 Km 1 mil subtends 200
metres and 124.444 mils subtends 24.888 Km( 124.444 * 200 / 1000 )
Even with a narrow beamwidth transmitting antenna you are painting a
really really big target at that distance. That means the aiming of
the transmitting antenna is not so critical, but it also means your
available energy is spread out a lot more. I'm thinking you want to
have a second transmitting antenna to switch to once you have done the
initial allignment that has as narrow a beamwidth as possibe to
maximize the energy available at the other end.
Peter melb_ap [21] 17-8-05 Not sure quite how your formula works,
whats the 6400 for ? Regarding transmit , yes i agree it's pretty
pointless covering a large area. Ideally we need an antenna with a
very narrow beam width , but moderate gain , so we can still use
enough power to light up the antenna adequately.
This'll probably come down to testing.
dna 20-8-05 I'm converting from degrees into Mils. there are 6400
Mils in a circle, so divide degrees by 360 ( dimensionless) and
multiply by 6400 gives the angle in Mils. I'm converting to Mils
because it's easy to extrapolate an angle to how long it is on the
ground at any distance. 1 Mil is 1 metre at 1000 metres so 124 Mils is
124 metres at 1000 metres and 24800 metres at 200 km.
So, the question is what sort of antenna gived a very narrow
beamwidth? I'm thinking it is probably a yagi with lots and lots of
elements or maybe even a phased array of such yagis.
Equipment Discussion
- what equipment and methods we could use for initial lineup
- what levels should we start at (ie should we start with
maximum power as for equipment , an fm carrier on 2.4 Ghz run by a
licenced ham was agreed upon by us
with a spec analyser on the other end as one of the easiest methods.
Also start with high power and wind it down to the minimum to see
what margins we have and if we can do it with ism band eirp limits, or
if not how much extra gain will be required to make it (is it
practical).
Site Suitability Surveys
- what locations for inital trial runs
- how practical are the sites for access - do we have to lug 100kg of
equipment up a hill
- time of year - ie the USA tests were done across the desert
to get the dryest air possible.
Peter melb_ap [26] 17-8-05 - from 12/8/05 mw meeting DN ratbaggy
[27], MC mjc [28], Peter melb_ap [29] ; Mike did a visit to camels
hump at mount macedon and reported that there is a 10 Minute walk to
the top with rocky terrain finishing the trip.
Is this correct for this site Tony ?
Mike hkf [30] 18-8-05 Concerns with the lack of open space and access
at camels hump site for the size of the equipment we would end up
needing. Also lack of LOS at ground level in the mt buffalo direction.
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Google Earth KMZ file showing Camels Hump and Mt Buffalo locations
MelbWirelessWiFiRecordAttempt.kmz [31]
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Links:
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[1] http://melbournewireless.org.au/?WorldRecordWIFILink
[2] http://melbournewireless.org.au/?TonyLangdon
[3] http://melbournewireless.org.au/?AdrianLodders
[4] http://melbournewireless.org.au/?MikeCampion
[5] http://melbournewireless.org.au/?HoracePinker
[6] http://melbournewireless.org.au/?DanFlett
[7] http://melbournewireless.org.au/?melb_ap
[8] http://melbournewireless.org.au/?HyperLink
[9] http://melbournewireless.org.au/?VoIP
[10] http://melbournewireless.org.au/?melb_ap
[11] http://melbournewireless.org.au/?melb_ap
[12] http://melbournewireless.org.au/?bigjohn
[13] http://melbournewireless.org.au/?melb_ap
[14] http://melbournewireless.org.au/?ratbaggy
[15] http://melbournewireless.org.au/?mjc
[16] http://melbournewireless.org.au/?melb_ap
[17] http://melbournewireless.org.au/?melb_ap
[18] http://melbournewireless.org.au/?ratbaggy
[19] http://melbournewireless.org.au/?mjc
[20] http://melbournewireless.org.au/?melb_ap
[21] http://melbournewireless.org.au/?melb_ap
[22] http://melbournewireless.org.au/?melb_ap
[23] http://melbournewireless.org.au/?ratbaggy
[24] http://melbournewireless.org.au/?mjc
[25] http://melbournewireless.org.au/?melb_ap
[26] http://melbournewireless.org.au/?melb_ap
[27] http://melbournewireless.org.au/?ratbaggy
[28] http://melbournewireless.org.au/?mjc
[29] http://melbournewireless.org.au/?melb_ap
[30] http://melbournewireless.org.au/?node
[31]
http://users.bigpond.net.au/flett/WiFiAttempt/MelbWirelessWiFiRecordAttempt.kmz
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