#220328 - 03/27/11 06:16 PM
Re: Improvised antennas
[Re: TANSTAF1]
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Veteran
Registered: 08/19/03
Posts: 1371
Loc: Queens, New York City
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Well, we wre not using HTs - in fact, HTs had NOTING to do with it
We ran the output of the WiFi card into a "linear amp" of the right frequency range
Your tech license is about a LOT more than "HTs" - it's about being able to use all of our frequencies above 50Mhz - for lots of different things. The lower part of the band (2.4 Ghz) what 802.11 b/g is in has Ham radio as it's primary allocation, and they TYPE of modulation used by wifi ) is allowed to us - aka we can build wifi radios with a LOT of output - Hint, per Part 97, on the modulation scheme used by 802.11g, we have a max permissible output power of - ready for this, 1500 Watts PEP (vs Milliwatts in Part 15 - aka what regular users use), throw that into a 24 dBi disk, and you have 376.8 Killowatts ERP coming out of the front of that dish (as I said, you REALLY REALLY don't want to walk in front of that dish, in fact, you don't even want to be in front of a standard Omni at those freqs and power levels - think 1500 watt microwave)
take a 2.4 Ghz radio, modulate it the right way, put it on the WiFi channel (say Ch1) - and you have WiFi - at high power
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#220340 - 03/27/11 09:00 PM
Re: Improvised antennas
[Re: gonewiththewind]
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Newbie
Registered: 07/27/10
Posts: 25
Loc: Born in ME, in exile in MA
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I guess from your username that you're an extra. I memorized enough to pass the technician test by taking the practice exams on QRZ. I don't have an elmer; I'm not in a club; I'm a 1968 liberal arts grad; Ive done non-technical work all my life. I know I do not know anything about amateur radio.
So what do the remote users use to connect? Did they have the same souped up linear amp? I understand your gateway has/can have a lot of power and remote users can hear it, but they need enough so it can hear their signal so I was wondering how it was done.
If I understand correctly you found you did not need a linear amp, but rather just a high power PCMCIA card plus the 24 db antenna.
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#220349 - 03/28/11 12:34 AM
Re: Improvised antennas
[Re: gonewiththewind]
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Veteran
Registered: 08/19/03
Posts: 1371
Loc: Queens, New York City
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OK, we were running (for that super long distance test) amps on both sides - what we did was basically put the long distance link on Ch1, and had a local, 'Normal' power link on, if I remember right, Ch6 for the users on both ends
End user connected to SSID KG2V (actually it was the guy who was running the tests call), the laptop routed it out to the HP card (which was a PCMCIA card), and away we went
We were not using a dish, but waveguide antennas - at 16 miles in NYC, we had to dig up real HP cards that had an external antenna port - they do exist, but I can't remember the brand (like I said, I was definately the pointy haired boss on this - left the details to two other guys
Both sides of the link were running similar gear, and the fact that we were using directional antennas on BOTH sides of the link gave us some advantage We did use HTs - mostly to talk to one another while aligning the setup.
Dig up some issues of QST, National Contesting Journal etc - and look at what they call 'the world above 50Mhz' - particularly 2.4Ghz contesting - these are guys who make LONG LONG distance contacts up in the band we think of as WiFi
The big thing you need to do is find an Elmer - I know that without folks like W2ML, WA2GUG, and the like, plus helping elmer newer guys like KC2LSB (who took over Queens Ares after I no longer had time, and then went on to become the DEC of NYC, and then the SEC)
Try searching out your local ARES group, but be careful, some of them are definately 'wannabe' police and the like - run away from that, but you can probably find a good mentor for the 50Mhz bands there.
The real fun comes when you upgrade, and can start playing lower down in frequency
BTW, I'm going to give one piece of advise to any new hams/potential hams reading - Don't sweat your first HT too much, nor your first mobile rig. They have a tendency to eithre get replaced, or more commonly, they multiply. I can remember sweating my choice of first HT (it was a great choice, and I gave it to a friend I've know for 35+ years when he got his ticket), but if I told you how many HTs and mobile rigs I have in service RIGHT NOW, you'd laugh - without getting out of my chair, there are 7 mobile units, and 8 HTs in arms reach!! (partly because I decided for MY use, I wanted to go with all single band units (aka seperate VHF and UHF radios), which doubles what you need, but if you do go that way, you can end up going commercial (I did) and sometimes you get 'package' deals "here is a lot of 10 identical radios...". That and I became friends with the local Commercial radio shop - and sometimes they get in older stuff that would be perfect for what I need, and the tech (also a ham) will leave a box on my rear steps
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#220372 - 03/28/11 12:13 PM
Re: Improvised antennas
[Re: gonewiththewind]
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Pooh-Bah
Registered: 07/11/10
Posts: 1680
Loc: New Port Richey, Fla
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Doug, guys.... does anyone have experience with the Gulo Gulo walking stick cellphone antenna (found on Wildernessgeek)...I could not find any dB gain information....I'm occasionally on the Gulf in a boat without marine VHF..though I could build my own if they proved worth while
Edited by LesSnyder (03/28/11 03:22 PM)
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