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Chessie

join:2011-02-02
united state

1 recommendation

High quality LMR cables.

Okay guys. I generally avoid using LMR extensions between an AP and the antenna. After having several fail in the past on backhauls and AP's I swore them off and moved the APs up the towers. However, I have one tower that is not climbable. Its a tilt up 62 foot. It does have a LMR on it right now and I have water infiltration in the cable. It needs to be replaced and because of the involved winching process and truck that needs to be hired to accomplish laying it down I don't want to install an AP at the top of the tower.
So can anyone recommend a company to purchase a cable from that you have had long term experience with the cable lasting?

Thanks in advance.



Rhaas
Premium
join:2005-12-19
Bernie, MO

1 recommendation

Tessco. They can make any type of jumper you want, or they have premade jumpers:
»www.tessco.com/products/productH···upId=412

»www.tessco.com/yts/industry/prod···dex.html
--
I survived Hale-Bopp!

gunther_01
Premium
join:2004-03-29
Saybrook, IL

1 recommendation

reply to Chessie

Anything you have made, you may want to have that company frequency sweep the cable to check it though. Most notable companies do this any way.
--
»www.wirelessdatanet.net


petecarlson

join:2004-11-06
Baltimore, MD

1 recommendation

reply to Chessie

I used to have the same problem but then switched to making all my own cables with real LMR-400 and EZ400NMH-D connectors. Haven't had an issue since but we stopped doing coax for anything but split mounts a long time ago.



superdog
I Need A Drink
Premium,MVM
join:2001-07-13
Lebanon, PA

1 recommendation

reply to Chessie

I also stopped using LMR400 for jumpers unless I absolutely had too. I still have a few locations that use them however. IMHO, anything from Times Microwave is good stuff. I bought 2 rolls of it awhile back and am still using that stock.

If you make your own cables and take your time and solder all of your center pins, you should have no issues. As mentioned, they should be swept but.............All of mine seem to work just fine?
--
»www.wavecrazy.net


Chessie

join:2011-02-02
united state

said by superdog:

I also stopped using LMR400 for jumpers unless I absolutely had too. I still have a few locations that use them however. IMHO, anything from Times Microwave is good stuff. I bought 2 rolls of it awhile back and am still using that stock.

If you make your own cables and take your time and solder all of your center pins, you should have no issues. As mentioned, they should be swept but.............All of mine seem to work just fine?

Thank you. Thats the type of feedback I was looking for. Any failures at all on the Times Microwave stuff? It apears the cable we have in place now is actually leaching moisture through the outer casing.

bburley

join:2010-04-30
Cold Lake, AB

1 recommendation

I would consider going to LMR-600. When I started this job there was a 100ft run of LMR-400 for a 900 MHz AP that was performing poorly. Replacing it with LMR-600 made a huge improvement.



John Galt
Forward, March
Premium
join:2004-09-30
Happy Camp
kudos:8

1 recommendation

reply to Chessie

said by Chessie:

Any failures at all on the Times Microwave stuff? It apears the cable we have in place now is actually leaching moisture through the outer casing.

Use this:

»www.tessco.com/products/displayP···ntPage=1


TomS_
Git-r-done
Premium,MVM
join:2002-07-19
London, UK
kudos:5

1 recommendation

reply to Chessie

Any reason you wouldnt use LDF instead?

Its probably more expensive, but has a solid corrugated shield instead of braid which helps keep water away from the core.

We used LDF1-50 for our microwave P-t-P feeders, and had a little 4-50 for certain installations when the radio was located indoors. Never a problem with them, even when the birds got at them. Just patch it up and move on.


wirelessdog

join:2008-07-15
Queen Anne, MD
kudos:1

+1 on LDF. We quit using LMR like 7 years ago LOL


gunther_01
Premium
join:2004-03-29
Saybrook, IL
reply to Chessie

IDK if this is acurate, but worth knowing for your application. It should be pretty close I would imagine.

A considerable difference between LMR-400 and .5" LDF.
--
»www.wirelessdatanet.net


Jim_in_VA

join:2004-07-11
Cobbs Creek, VA
kudos:4
reply to bburley

bet that LMR600 was a bear to run, unless it was straight-line
--
... need help? »evdo-tips.com/


Hahausuck
Premium
join:2003-12-14
kudos:2

600 is pretty easy to run compared to Hardline. We used to plumb DAS's in using 600 instead of LDF4 because it could go around corners easier.



Jim_in_VA

join:2004-07-11
Cobbs Creek, VA
kudos:4

really, 600 goes around corner's easy? The radius must be slight, that is is some thick stuff
--
... need help? »evdo-tips.com/



John Galt
Forward, March
Premium
join:2004-09-30
Happy Camp
kudos:8

said by Jim_in_VA:

really, 600 goes around corner's easy? The radius must be slight, that is is some thick stuff

The recommend bend radius for most cables is 10x the diameter of the cable. Less than that and you will get center conductor migration and impedance changes.

Hahausuck
Premium
join:2003-12-14
kudos:2
reply to Jim_in_VA

Easier than hardline..... Still gotta be careful and mindful of what you are doing with it.



Jim_in_VA

join:2004-07-11
Cobbs Creek, VA
kudos:4

one would only use 600 for tower feeds, nothing else...correct?
--
... need help? »evdo-tips.com/


Hahausuck
Premium
join:2003-12-14
kudos:2

You could. I made sure it wasn't used outside though.....


wirelessdog

join:2008-07-15
Queen Anne, MD
kudos:1

1 recommendation

reply to Jim_in_VA

Most reputable companies I know of would never use any LMR on a tower, period. 600, 400, junk is junk.


Hahausuck
Premium
join:2003-12-14
kudos:2

Yep. I prohibited braided style cables. I only permitted hardline types. Too many potential issues could creep up over the years.



Jim_in_VA

join:2004-07-11
Cobbs Creek, VA
kudos:4
reply to wirelessdog

Times Microwave is junk?


wirelessdog

join:2008-07-15
Queen Anne, MD
kudos:1
reply to Chessie

I take it you haven't visited many tower sites. LDF is what is used.

LMR has high loss, shitty connectors, low reliability.

Like I said, we quit using LMR years ago.



Jim_in_VA

join:2004-07-11
Cobbs Creek, VA
kudos:4

1 recommendation

I take it you have no idea of the range Times-Microwave makes of cables, I'm not promoting their product ... just saying
--
... need help? »evdo-tips.com/


Hahausuck
Premium
join:2003-12-14
kudos:2
reply to Jim_in_VA

Not junk. It's very high quality stuff. Indoors it's fantastic. Outdoors is better served by hardline.


Chessie

join:2011-02-02
united state
reply to Chessie

Well unfortunately I already have a new LMR 600 cable on its way from Tesco. My partner had already decided he would like to encase it in a plastic piping we have use at tower site in the past to protect cables between the building and towers. I have no doubt he can make it waterproof but It would be a heck of a lot easier to throw the LMR cable on the shelf of unused parts and just order a LDF cable instead. So does anyone have a good source for a 70ft run or it? What size should I be looking for it appears it has little loss on 900mhz.


wirelessdog

join:2008-07-15
Queen Anne, MD
kudos:1
reply to Chessie

I was referring to types of cable not manufacturer. Nice try, I didn't take the bait.



Jim_in_VA

join:2004-07-11
Cobbs Creek, VA
kudos:4

so wirelessdog is a expert on cable specs now ...how did you get to be that?
--
... need help? »evdo-tips.com/


Hahausuck
Premium
join:2003-12-14
kudos:2
reply to Chessie

Since its on the way just use it.


wirelessdog

join:2008-07-15
Queen Anne, MD
kudos:1

1 recommendation

reply to Jim_in_VA

Jim:

Perhaps you would be wise to show some respect in this forum. We aren't a bunch of clowns doing this for a hobby. We live, breathe and work RF and I don't mean hooking up amp's, repeaters, and helping a few out by a website providing assistance with the customer side of mobile broadband.

Most of us here climb towers, sweep cables, and engineer links that can earn the title of carrier class.

You are not a peer here, you do not own or operate a WISP. You are a customer of one and dabble in mobile broadband solutions.

It would do you good to read the rules and the forum README located here:

»WISP Forum README


bburley

join:2010-04-30
Cold Lake, AB
reply to Chessie

The 100ft LMR-600 has been in use for over 5 years now without any issues. It runs mostly straight up the tower but does have some bends in it, nothing radical, no 90 degree corners.

I have heard that enclosing cables in pipe or conduit can also run the risk of being a moisture trap. I haven't done that so I can't comment on best practices to prevent or release moisture.