How much of the cable is copper? The telemetry folks went to aluminum cable
(big stuff with a smooth not corrugated solid shield ) a long time ago....
Just Curious,
Joe kk0sd
________________________________
From: TowerTalk <towertalk-bounces@contesting.com> on behalf of Steve Maki
<lists@oakcom.org>
Sent: Saturday, February 4, 2017 6:20 PM
To: towertalk
Subject: Re: [TowerTalk] Introduction
Yup. The only coax we're installing nowadays is to replace damaged
stuff. On new builds and upgrades, we run "hybrid" cable which is
(12-18) fibers and multiple power pairs. The driver here is to get the
transceivers as close to the antenna as possible, which reduces PIM,
which is necessary for high data rates. It's a nice situation for tower
crews - we are needed whenever there is a radio failure.
The existing coax infrastructure remains in use for 2G (GSM & CDMA) and
3G (UMTS), but all that will be shut off in the near future. Whether the
old coax will be removed (and ends up on the surplus market) depends
largely on the price of copper and what the customer (carrier) can save
in lease fees from the tower owners. Metal buyers really don't like
coax, it's too messy to recover the copper.
-Steve K8LX
On 2/4/2017 18:36 PM, Jim Thomson wrote:
> As KK9A mentioned, the surplus market for 7/8" and larger coax will be
> gradually drying up in the future. Virtually all new cell site builds
> are utilizing tower top radios connected via fiber. 1/2" is still used
> and will continue to be used for jumpers between the radios and
> antennas, although we also are currently using "Air" antennas which have
> the radios built in.
>
> Since the cell market has been the major source of well priced surplus
> Heliax style cable...get it while you can.
>
> -Steve K8LX
>
> ## agreed, heliax .875 inch and larger, has gone the way of the do-do bird.
> I retired from the local telco back in nov 2009, and several months b4 that,
> I was at a cell site one day, and saw em installing fiber optic cables to the
> top
> of the freestanding 90 ft tall concrete tower. Tower originally had 4-5 huge
> microwave dishes on it for a heavy route system.
>
> ## I think G3 cell service was just being rolled out prior to my retirement.
> Several other cell carriers had ants on our tower, and one of em went the
> fiber optic route 1st. Everybody else followed. No coax used at all on
> any cell tower
> these days. Now whether the old heliax was removed is another matter. A
> lot of times
> its just left in place. No budget for removal and shipping and disposal. No
> time either.
>
> ## It might get eventually removed..at great expense. We went through semi
> trailer loads of
> the larger heliax. Cell sites being slammed in every week at one point.
>
> ## If u see it surplus, buy it if its in good shape. But dont expect
> continuous runs of much more
> than 150 ft. Earlier days they used N connectors, then later to 7-16
> DIN. If u see the surplus
> 7-16 dins, snag them too. 1.125 inch heliax was used quire a bit as well,
> depending on freq used,
> and length involved.
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