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5 watt amp

PostPosted: Thu Jun 05, 2003 9:02 pm
by recompiler1
I just got a 5watt amp that I wil lhookup to my linksys access point, and a 9dbi maxxrad antennae. I will mount it inside, with the patch antenae facing out the window for now. I was wondering if anyone had similar setups, and the safeguards they took not to cook themselves or pedestrians.

PostPosted: Fri Jun 06, 2003 4:45 am
by Madhadder
5 Watt!!!!!!

I don't even want to know how much you paied for such a beast...
Wait a minute.. Yeah I do?
How much & where...


PS: Be on the Lookout for MIB trucks looking for your setup..
Something about those pesky FCC regs...:D

PostPosted: Fri Jun 06, 2003 5:04 am
by Thorn
recompiler, unless you are a ham, the setup is highly illegal under FCC law. Your effective radiated power is at 40W.


Besides being illegal, it is potentially dangerous. Doing some quick calculations, my figures show that no one should be within several feet of the antenna when it is on. The near field radiation is that high.

PostPosted: Fri Jun 06, 2003 6:24 am
by recompiler1
I have this one
http://www.ydi.com/products/amp2440-amplifier.php

Thanks for the figures. I guess I'll mount it outside ASAP. When I gt my HAM license it'll be legal for me to use it right?

PostPosted: Fri Jun 06, 2003 7:10 am
by Thorn
Originally posted by recompiler1
I have this one
http://www.ydi.com/products/amp2440-amplifier.php
...

Well, if it's that one, the maximum is 0.5W. If thats the case, then you are probably legal as your total output is 36dBm. The near field is lower then, and you should be OK. Personally, I still keep people a foot or so away went it is on.

Originally posted by recompiler1
... Thanks for the figures. I guess I'll mount it outside ASAP. ...

If it isn't legal, you'd be better off not running it. You could be facing potentiall fines of $10000/day.

Originally posted by recompiler1
... When I gt my HAM license it'll be legal for me to use it right?


Within the confines of the ham band that overlaps the ISM band, yes. Hams are allowed up to 10W (if I remember correctly.)

PostPosted: Fri Jun 06, 2003 7:18 am
by recompiler1
thank you for clearing that up

PostPosted: Fri Jun 06, 2003 8:02 am
by agentgrn
Originally posted by Thorn
Within the confines of the ham band that overlaps the ISM band, yes. Hams are allowed up to 10W (if I remember correctly.)
I'll have to break out my study guide again, but I don't recall any specific limit on the amateur band...then again, hams are also required to use the minimum power possible to maintain communications in any of the bands they use.

PostPosted: Fri Jun 06, 2003 6:05 pm
by mvario
Which model did you get?

The way it looks to me is that the -F modifies full imput power (up to 100mw/20dbm) up to 16db. So it looks like the -F would give you 36dbm, or about 4watts.

PostPosted: Fri Jun 06, 2003 6:59 pm
by michaelp
isnt that the 500mw one?

PostPosted: Fri Jun 06, 2003 7:44 pm
by recompiler1
There are no special markings on it, so I'll assume its the standard -F option. I traded it from one of the guys on netstumbler forums.

PostPosted: Fri Jun 06, 2003 8:19 pm
by Thorn
According to the specs, the -F model is a linear amp which goes to a maximum of 500mW (0.5W, 27dBm.) http://www.ydi.com/products/amp2440-amplifier.php?screen=specs

PostPosted: Fri Jun 06, 2003 8:24 pm
by recompiler1
I miss converted in my head 500mw to mean 5 watt instead of .5 watt. Hell of a big difference. My mistake.

PostPosted: Fri Jun 06, 2003 8:28 pm
by Thorn
Originally posted by recompiler1
I miss converted in my head 500mw to mean 5 watt instead of .5 watt. Hell of a big difference. My mistake.


Hardly a big deal. We've all dropped a decimal point at one time or another. :) I was just concerned about the safety issue when I saw the original post.

PostPosted: Fri Jun 06, 2003 8:34 pm
by recompiler1
I was concerned about safety too. I was worried about my/room mates/bystanders safety and FCC medling. The radio club in my school has been in enough hot water with FCC over the years (somewhat lengthy but hillarious story).

PostPosted: Fri Jun 06, 2003 8:38 pm
by sparafina
Originally posted by agentgrn
I'll have to break out my study guide again, but I don't recall any specific limit on the amateur band...then again, hams are also required to use the minimum power possible to maintain communications in any of the bands they use.


Hams can go up to 100 watts, but I'm not sure why anyone would. WiFi DXing to the moon?