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Walden
11-26-2007, 10:19 PM
How would i go about reducing the power (range) on the 5w fm transmitter?

http://cgi.ebay.com/5W-FM-Stereo-Transmitter-Black-Antenna-Power-Supply_W0QQitemZ230194095949QQihZ013QQcategoryZ467 5QQcmdZViewItem
xmus
11-26-2007, 10:44 PM
How would i go about reducing the power (range) on the 5w fm transmitter?

http://cgi.ebay.com/5W-FM-Stereo-Transmitter-Black-Antenna-Power-Supply_W0QQitemZ230194095949QQihZ013QQcategoryZ467 5QQcmdZViewItem

With a 50Ohm 10Watt resistor.

(1/2 joking).

what you are talking about is "effective radiated power"

To reduce this
1) use a really long piece of coax
2) use a really badly matched antenna (not too bad, or you'll hurt your transmitter)
3) hide the antenna behind some concrete on all sides.
4) mount it as low as possible.
5) mount it sideways rather than vertically.

But 5Watts is way too much power to reduce it with the methods above.... You'll still be way too strong.
Walden
11-26-2007, 10:46 PM
Ok thanks. Ill just hid it im my basement. :)

I didnt realy think of that lol
xmus
11-26-2007, 10:57 PM
Ok thanks. Ill just hid it im my basement. :)

I didnt realy think of that lol

how close will people be to the antenna? You wouldn't want folks sitting right next to it for long periods.
Walden
11-26-2007, 11:11 PM
Um no where. It's 300 ft to the road and my basement is underground (DUH) lol is that the info you want.
xmus
11-26-2007, 11:38 PM
What i meant was, how close will people be in the house to the antenna, and for how long? you have cats? dogs? can they get close to the antenna? kids?
Walden
11-26-2007, 11:43 PM
My basement door is allways closed so no cats get in there. So everyone is atleast 8 ft. away if you are directly above the antenna. Then pluss more ft for where you are on the second floor.
xmus
11-27-2007, 12:28 AM
My basement door is allways closed so no cats get in there. So everyone is atleast 8 ft. away if you are directly above the antenna. Then pluss more ft for where you are on the second floor.

I don't have the RF exposure chart memorized, but that sounds reasonable. The danger zone is very close and perpendicular to the antenna. Straight up and down there is much less radiation. (Assuming you are using a vertical antenna, or dipole, and that the antenna is strung up vertically)
Walden
11-27-2007, 01:16 AM
YAY i just won the 5w transmitter!!!!!!

I cant wait to get it and try it out. :DDDDDDDD