About 6 months ago I mounted a 5.8 GHz wireless networking system on a 600 ft tower with LOTS of land mobile and and 8 FM broadcast stations. The data radios were on the back side of 4 ft dishes using Power over Ethernet on the tower at the 150 foot level.
I used shielded CAT-5 and it all as been working great. I agree with the other recommendations you have been given, make all the cable run shielded and then see if you have any problems. Most networking guys DO NOT understand anything about RF. ------ Original Message ------ Received: Thu, 20 Nov 2008 11:42:50 PM PST From: Mike Morris WA6ILQ <[EMAIL PROTECTED]> To: [email protected] Subject: Re: [Repeater-Builder] Re: 2.4 Ghz wireless radio and 145.410 repeater > At 06:28 PM 11/20/08, you wrote: > >--- In [email protected], Ken Arck <[EMAIL PROTECTED]> wrote: > > > > > > At 05:16 PM 11/20/2008, n9lv wrote: > > > > > > >I just had a 2.4 Ghz internet wireless antenna mounted at the top > >of my > > > >120' tower which is where the antenna is for the 145.410 repeater. > >I > > > >am getting intermod into the system that causes it to hang open. > > > > > > <----Couple of questions: > > > > > > 1) You say "intermod". Exactly what kind of interference are you > >experiencing? > > > >It is opening and closing the receiver very quickly. You can > >actually hear the pulsing of the wi-fi radio. > > > > > 2) Is this "wireless antenna" actually a radio/antenna combination > > > being fed power via POE (Power Over Ethernet) over a CAT5 cable up > >the tower? > > > >Yes, this is a wi-fi radio and antenna combination setup with cat5 > >POE. I am not sure the brand, all i can see with what they showed me > >is something about Canopy. > > > >Mathew > > Canopy is a Motorola product. I'd start with a Google search on Motorola > Canopy plus any model number I can find on the unit (which may require > climbing the tower if the Canopy system you have uses an active antenna). > > Are the antennas mounted side by side or over and under? > Is the Canopy antenna directional? Most of the client side are, but not all. > > I'd start by putting the Canopy antenna an odd number of quarter wavelengths > (i.e. 3/4 wave) of the longest wavelength under the repeater antenna. > Since the 2m wavelength (just about 78.7 inches) is so much longer than > the Canopy wavelength, I'd start at 3/4 of 79 which is just about 59 inches. > So I'd start my experimentation by mounting the Canopy antenna about 5 feet > under the 2m antenna. > > If the Canopy antenna is an active panel antenna, i.e. one with the RF > system mounted inside the antenna housing and fed by CAT-5 cable > (most are) I'd make sure the housing is shielded and you are using > shielded cable to feed it. > > Mike WA6ILQ > >
