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Eliminate RF Exposure With Ground ??

Apr 16th, 15:39

KE7KEB

Joined: Sep 29th 2006, 11:28
Total Topics: 0
Total Posts: 0
Hello All,

I would like to install a Mazzoni Baby loop antenna ~6' above the peak of the comp roof on my single story home, to be operated at 100 watt max power on HF bands.

Would it be effective to eliminate / lessen RF exposure inside the home by installing a grounded 2" x 2" wire screen throughout the attic floor, which is ~15' below the base of the antenna?

I appreciate everyone's brilliance!

73, john
Apr 17th, 06:31

W1VT

Super Moderator

Joined: Apr 4th 1998, 00:00
Total Topics: 0
Total Posts: 0
It would help a little, but RF will easily leak around the edges of the shield. These days it is hard to use an attic or above roof antenna, as electrical wiring in the attic will propagate noise from electrical and electronic devices in the home. You may be able to do a test with an indoor antenna to see whether this may be an issue. Perhaps ten feet of wire attached to the center pin of a PL-259. Run a radio off batteries and see whether shutting of the main breaker and waiting for the power to run down (sometimes it takes a few minutes in some devices) and see whether the noise level changes.

Zak W1VT
ARRL Senior Lab Engineer
Apr 17th, 13:30

KE7KEB

Joined: Sep 29th 2006, 11:28
Total Topics: 0
Total Posts: 0
I was originally more concerned with irradiating myself (glow-in-the-dark?) with the close proximity to the magnetic loop antenna (even though I was only planning to run 100 watts), but didn't even consider interference generated by the AC wiring in the attic. Thanks for the heads-up on this potential issue! I had planned on laying the grounded wire screen wall-to-wall on the attic floor for my personal protection, which may also attenuate interference from the AC wiring radiating upwards to the antenna? I agree with your test recommendation. Thank you Zak, 73 john

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