Repeater Setup

JD · Post by JD » Fri Apr 21, 2006 6:03 am

I have a company that wants to place either a VHF or UHF 30 watt repeater on the same structure as a 900 MHZ unlicensed internet provider. As long a s I do not run the 7/8" cable parallel to the other system and vertically seperate the antennas, does anyone see a problem?

Thanks.

Rayjk110 · Post by **Rayjk110** » Fri Apr 21, 2006 1:13 pm

Nope, it should all be good if you do as said. Just give a few field tests one up, and if everything is working fine, it should be good.

Vercomm · Post by **Vercomm** » Wed Apr 26, 2006 10:19 am

Curious as to why you are wanting to seperate the 2 Tx lines. One is 900MHz and the others are UHF/VHF, there shouldn't be any problems running the line beside each other. Would like to hear your thoughts on that

JD · Post by JD » Wed Apr 26, 2006 11:57 am

This is going to be done at the request of the internet system tech No parallel lines!!!!!

I would be welcome to your input.
Thanks

jim · Post by **jim** » Wed Apr 26, 2006 12:04 pm

Tell this "internet systems tech" to stivk to his job and leave the radio to the radio guys!

Vercomm · Post by **Vercomm** » Wed Apr 26, 2006 5:41 pm

The only reason i asked is it seems a bit silly that the internet guy has concerns about your line being next to his. You aren't using 'leaky' cable so there would be no problem. Depending on your antenna type a decent amount of space between them would be all I would worry about. make sure that the VHF/UHF aren't having VSWR problems because the antennas are too close together. Other than that "have at her" the frequency seperation between 900Mhz and your repeater is lots & lots.

Curiosity got the better of me!!

JD · Post by JD » Thu Apr 27, 2006 6:38 am

Thanks. The company has an exclustivity clause on the strycture. When I called and talked to them, they did not have a clue on frrquencies, line loss, etc. I had to get their okay though.
My VHF antenna will be 4 to 6 feet above theirs.

tvsjr · Post by **tvsjr** » Thu Apr 27, 2006 6:53 am

There's also the possibility that the WISP cable running up the tower may be Ethernet. Because of the loss at higher frequencies (more prevalent at 2.4 than 900), they'll commonly run the data up the tower to convert it to RF at the top.

Besides, if you don't have to tie the cables down next to each other, why do it? If nothing else, just in the interest of keeping the peace. Plus, it sounds like the building space might just be donated... in which case, you do whatever the site owner/manager tells you to do, however ridiculous it might be.

As far as the interference issue, if you're on a commercial site, I do hope you're running a good duplexer with an isolator stage (single or dual)...

5-sides · Post by **5-sides** » Mon May 01, 2006 6:36 am

The only concern I would have is if you are going to be close to a 1/2 wave if you put the UHF rptr in. Unless you are getting up into the T-band range, it should be no concern at all. I wouldn't worry about a VHF in the 150-160 range, as the harmonic would be far enough (1/6th). Plus, even though 4-6 feet is not spectacular, it should be enough given that you are only dealing with a possible harmonic.