Kurt,
It is used in the cellular industry to cover bi-metal junctions that are
sources of near field Passive Inter-Modulation (PIM). The tape blocks the RF
sources from mixing at these points and prevents the generation of additional
interfering signals at frequencies used by receivers at a site.
In other cases, the RF sources involved are simple harmonics from high power FM
transmitters. For example, a 101.1 MHz transmitter can produce a strong 7th
harmonic on 707.7 MHz which is in the middle of a cellular uplink passband.
Interference there can crowd out weak cell phone signals. I've seen cases
where the spectral purity from the FM broadcaster's antenna is fine, but a
poorly designed, or missing cover on the transmitter itself is allowing for
unfiltered RF harmonics to be emitted. Tape has been applied to either fix the
problem, or to convince those involved to implement a more permanent solution.
There are other uses, but these are two common applications.
73,
Gordon Beattie, W2TTT
201.314.6964
Get Outlook for Android<https://aka.ms/ghei36>
________________________________
From: RFI <rfi-bounces+w2ttt=att.net@contesting.com> on behalf of KD7JYK DM09
<kd7jyk@earthlink.net>
Sent: Wednesday, June 16, 2021 1:27:58 AM
To: Rfi List <RFI@contesting.com>
Subject: [RFI] EMI Tape?
Who's playing with this, what is your application, and results?
https://www.ebay.com/itm/121739046153
I've seen it in equipment since the 90's, bought a roll a couple years
ago, just haven't gotten around to using it. Wondering what others are
doing.
Kurt
_______________________________________________
RFI mailing list
RFI@contesting.com
http://lists.contesting.com/mailman/listinfo/rfi
_______________________________________________
RFI mailing list
RFI@contesting.com
http://lists.contesting.com/mailman/listinfo/rfi
|