The problem is the permeability of air is very low compared to a metallic
core.
It would help a bit.
-----Original Message-----
From: George Skorup
Sent: Wednesday, June 7, 2017 12:00 PM
To: af@afmug.com
Subject: Re: [AFMUG] Interference on a repeater at 149 MHz
Could you not put a couple turns on the cat5's at both ends to choke it?
On 6/7/2017 9:31 AM, ch...@wbmfg.com wrote:
You put ferrite close to the source of the noise, so close to the radios
and if that does not do it, close to any switch or router on the other end
of the run. Clamps or rings will both work. I prefer clamps.
-----Original Message----- From: Craig House
Sent: Wednesday, June 7, 2017 8:27 AM
To: af@afmug.com
Subject: Re: [AFMUG] Interference on a repeater at 149 MHz
They are Mylar shielded cat5 cables If you mean in conduit though no
they are not in conduit.
If someone thinks the ferrite solution is worth a try what ferrite do you
use. Clamps or rings? One end of the cable or both? If rings, how many
loops of cable through them?
Sent from my iPhone
On Jun 7, 2017, at 09:10, Bill Prince <part15...@gmail.com> wrote:
Are the cat5 runs shielded? We've seen 100 Mbps ethernet can radiate in
the 140 MHz range. Shielding usually fixes it.
bp
<part15sbs{at}gmail{dot}com>
On 6/6/2017 1:17 PM, Craig House wrote:
We have equipment located on to Towers one is a water tower the other is
a guyed110 foot tower. In both locations there are two way repeaters
located on the towers that are receiving interference from what appears
to be our equipment. Nothing is substantially common between the way the
two towers are built out. The water tower had all of the equipment on
top of the tower at one point and we have since moved all of our
backhauls down to the catwalk railing on the opposite side of the tower
from the two-way repeater attempting to put some distance between our
equipment and the repeater but has not solve the problem.
We have ePMP both 2.4 sectors and the 5 GHz Omni as well as some
ubiquity air fiber five and Power beam M5 radios on the water tower all
running off of net tonics 24 port switch and the microtik router. The
other Tower has only a few m5 radios and and M2 Omni. It also has an air
fiber 5X amount of lower on the Tower around 55 feet. Everything on this
Tower has ethernet cable's running to the base where our equipment is
running from an old CMM micro or their own power supplies in the case of
the air fiber. Everything at this Tower is located inside of a metal
communications cabinet at the base. In both locations we have removed
old 900 FSK radios which were a source of interference but the problem
seems to have come back. I'm looking for ideas on what others have found
may be the source of interference or solution because I'm tired of
throwing darts blindfolded and hoping I find the right Target.
Sent from my iPhone
