Jim,

This situation happens all too often, and it usually occurs because cheap
equipment is used (plastic boxes to contain the amplifier, unshielded cable,
no ferrites, ineffective grounding. etc.) to keep the installation costs
down.  This is a misguided approach, because repeated visits to fix a
leakage problem will always cost a lot more than a first-class system would
have cost.  Sound familiar?

Another possible factor is that *some* wireless installers are primarily IT
(Information Technology) folks who have relatively little experience with
the RF environment at a repeater site.  I have met a few of these clueless
guys, whose eye glaze over when I talk about an interfering carrier from a
CPU crystal or intermodulation.  They're used to installing APs and bridges
in office buildings, and don't see anything different about tie-wrapping a
more powerful box to a tower that supports many other services, except
perhaps using some electrical tape and silicone goop to waterproof the
connectors.  Don't laugh- it happens!

So, to answer your question, immediately contact the wireless system owner
and advise him that his system is interfering with yours, and it must be
fixed promptly.  Don't quote the FCC rules quite yet.  If the polite
approach does not get results, contact the site owner.  Above all, do not
just sit and wring your hands.  The wireless owner must comply with Part 15
rules, but he must be told if there is a problem.

73, Eric Lemmon WB6FLY


-----Original Message-----
From: [email protected]
[mailto:[email protected]] On Behalf Of Jim Russell
Sent: Friday, April 24, 2009 7:20 PM
To: [email protected]
Subject: [Repeater-Builder] Computer noise in 2M Repeater



Does anyone have any suggestions on how to eliminate noise generated by a
Wireless 
Internet System. The owner of the tower where our club has our 145.370 MHz
repeater 
has rented space to a group who have mounted a wireless Internet "relay" on
the tower.  
The system is simple, it consist of a Netgear switch, a Microwave dish and a
smallYagi.  
There is approx. 300 feet of Cat 5 wire going up and 300 feet coming down
the tower.  
Their antennas are mounted within a few feet of ours on the top of the 260
ft. tower.
We unplugged the netgear switch and the noise cleared, we disconnected our 
antenna and the noise goes away.  The noise rides on the repeater receiver
squelch tail.
We do use a PL tone or we wouldn't be able to use our repeater at all
 
Jim WK5Y

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