Frank et al:
I have built screen rooms a couple of times. One was at Avco Everret
Research Labs in Everret, Mass. Their was a high powered FM and TV
tower next door. The first attempt was not satisfactory. (we could
watch TV
inside the screen room with rabbit ears.) We found that the signals
were getting in via the outer conductor of the cables even though they
grounded and travelled many feet through metal conduit. Eventually,
through very meticulous work we reduced the TV station a little over 110
Db.
I just built a 12 by 20 foot Shack in my back yard. I'm
experimenting with the emp protection information in the Polyphase
manual/catalog. I also put
copper screen in the walls, ceiling, floor. So far this is a total
waste of effort/money. The windows act as slot antennas (even though
they have grounded copper screens), and some signals (vhf) are stronger
inside than out.
Jim W0OOG/5
>Original Message-----
From: ftbrady@cosmoslink.net
Sent: Thursday, July 10, 1997 9:01 AM
To: towertalk@contesting.com
Subject: [TowerTalk] shack shielding
I forgot to mention why I was asking about shielding the shack during
construction. For years now, I've put up with the wierd rfi from the
kids
and neighbors tv sweep oscillators and video games. Since my antenna is
going to be well away and up from the local noise sources, I thought it
might be effective to also eliminate the direct radiation from those
sources
into my receiving equipment.
Is shielding of a room impractical or inefficient? Can it keep out rfi?
73,
Frank
--
FAQ on WWW: http://www.contesting.com/towertalkfaq.html
Submissions: towertalk@contesting.com
Administrative requests: towertalk-REQUEST@contesting.com
Problems: owner-towertalk@contesting.com
Search: http://www.contesting.com/km9p/search.htm
--
FAQ on WWW: http://www.contesting.com/towertalkfaq.html
Submissions: towertalk@contesting.com
Administrative requests: towertalk-REQUEST@contesting.com
Problems: owner-towertalk@contesting.com
Search: http://www.contesting.com/km9p/search.htm
|