[SBE] SBE Digest, Vol 30, Issue 9

[Rolin Lintag]

I have not seen it mentioned here yet but just to pitch in the idea that salvage companies should be part of the solution. Here in our place, we have contacted all the salvage companies we can think of who will buy scrap copper and metals for that matter. The local police is notified whenever there is someone selling copper (DIGITAL PICTURES ARE TAKEN). These salvage companies also know how a coaxial cable looks lke so they know that only telecoms/broadcast entities should sell them.

Thieves will have to go out of state to sell their booty.

Another thing that thieves fear is being identified and caught (on tape or disk) on the act. Security cameras should help and warnings that these are in use in the facility should be posted (if the thieves know how to read in the first place).
________________________________________
From: sbe-bounces at sbe.org [sbe-bounces at sbe.org] On Behalf Of sbe-request at sbe.org [sbe-request at sbe.org]
Sent: Monday, February 18, 2008 12:50 PM
To: sbe at sbe.org
Subject: SBE Digest, Vol 30, Issue 9

Send SBE mailing list submissions to
        sbe at sbe.org

To subscribe or unsubscribe via the World Wide Web, visit
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SBE Roundtable

Today's Topics:

   1. Re: Theft of copper radials (Gary Kline)
   2. Re: Tarring Copper (k7cr)


----------------------------------------------------------------------

Message: 1
Date: Mon, 18 Feb 2008 09:55:35 -0500
From: "Gary Kline" <gary.kline at cumulus.com>
Subject: Re: [SBE] Theft of copper radials
To: <crisa at crawfordbroadcasting.com>,   "'sbe member discussion mail
        list'" <sbe at sbe.org>
Message-ID: <00fd01c8723e$51313fa0$f393bee0$@kline at cumulus.com>
Content-Type: text/plain;       charset="us-ascii"

Seems they like to not only steal copper at our sites but AC units as well.



-----Original Message-----
From: sbe-bounces at sbe.org [mailto:sbe-bounces at sbe.org] On Behalf Of Cris
Alexander
Sent: Monday, February 18, 2008 9:40 AM
To: 'sbe member discussion mail list'
Subject: Re: [SBE] Theft of copper radials

We have had very little taken in the way of radials. They go for the strap,
the bus bars and the copper screen. Using copperweld has not helped at
all... These people are too dumb to realize what it is. If it shines like
copper, it's gone.

______________________________
Cris Alexander, CPBE, AMD, DRB
Crawford Broadcasting Company
Denver, Colorado
(303) 433-0104
(303) 433-0905 Fax
Member AFCCE


-----Original Message-----
From: sbe-bounces at sbe.org [mailto:sbe-bounces at sbe.org] On Behalf Of Mike
Langner
Sent: Sunday, February 17, 2008 7:15 PM
To: sbe member discussion mail list
Subject: Re: [SBE] Theft of copper radials

Among the things I've done -- several of which I've listed in previous posts
-- is use copper-clad aluminum.  It's virtually worthless as scrap -- and I
left a lot of short pieces on the ground so that thieves would learn from
where they "fence" their booty that there is no value. It worked until I
retired.  After that, I have no idea. . .

Nowadays, annealed copper clad steel is available from Copperweld -- it's
been used by the US Government in buried applications for years. Unlike the
hard-drawn Copperweld we've all fought to keep from tangling badly, the
annealed isn't springy and is easy to work with. Copperweld has extensive
tests that indicate the longevity in the ground is excellent.

I have no connection with or interest in Copperweld --

Mike Langner
Albuquerque, NM
_________________________


-----Original Message-----
From: sbe-bounces at sbe.org [mailto:sbe-bounces at sbe.org]On Behalf Of k7cr
Sent: Sunday, February 17, 2008 6:59 PM
To: sbe member discussion mail list
Subject: Re: [SBE] Theft of copper radials


I've been thinking about this issue...Here's a thought or two -

Install the normal ground system, except around the tower, where thieves
like to dig first, Place a 'dummy' ground system down, then about 6 inches
below that, put in the real McCoy.

or

Still wonder what's wrong with a few strategically placed Jacob's Ladders
around the tower? Seems to me that something to scare away the bums, inside
the tower fence of course, could
be helpful.   The problem is that there is nothing around a standard
AM tower that would give the appearance that someone might get hurt.
Certainly Danger-High-Voltage signs won't do it, but
something that actually looks threatening might.   Should check
this out with your lawyer first.

Clay Freinwald


----- Original Message -----
From: "Dan Rapak" <DanRapak at verizon.net>
To: "sbe member discussion mail list" <sbe at sbe.org>
Sent: Sunday, February 17, 2008 3:47 PM
Subject: [SBE] Theft of copper radials



> I've been following this thread for awhile. I seem to recall many

> years ago (the 70's perhaps?) that a station was having problems with

> their ground radials being stolen repeatedly. They did a little

> engineering work and ultimately received permission from the FCC to

> replace the radials with barbed wire. Cheaper to replace the barbed

> wire periodically when it deteriorated than to constantly replace the

> stolen copper. There was reportedly very little impact on their signal

> coverage and the thievery abruptly ceased.

>

> I'm sure the effect on signal coverage would have a great deal to do

> with the conductivity of the native soil, but for what its worth.....

>

> Dan Rapak

> _______________________________________________

> SBE mailing list

> To unsubscribe, go to http://seven.pairlist.net/mailman/options/sbe

> _______________________________________________

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> http://seven.pairlist.net/mailman/listinfo/sbe

>

>


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------------------------------

Message: 2
Date: Mon, 18 Feb 2008 10:49:45 -0800
From: "k7cr" <k7cr at blarg.net>
Subject: Re: [SBE] Tarring Copper
To: <crisa at crawfordbroadcasting.com>,   "sbe member discussion mail
        list" <sbe at sbe.org>
Message-ID: <016201c8725f$0b9cbca0$0200a8c0 at DB36LQ71>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
        reply-type=original

Here in the PNW a station that has been hit a couple of times
elected to paint all their copper a distictive bright color.  Then,
working with local law enforcement and scrap dealers, put the
word out to look for copper with that color paint.   Chances
are these thugs won't scrape it all off.   In this way they have a
chance of catching them....again - after- the damage has been
done to their system.

Clay Freinwald
----- Original Message -----
From: "Cris Alexander" <crisa at crawfordbroadcasting.com>
To: "'sbe member discussion mail list'" <sbe at sbe.org>
Sent: Monday, February 18, 2008 6:45 AM
Subject: [SBE] Tarring Copper



> Tarring the copper strap didn't help a bit in Birmingham. They took it

> anyway, goo and all.

>

> ______________________________

> Cris Alexander, CPBE, AMD, DRB

> Crawford Broadcasting Company

> Denver, Colorado

> (303) 433-0104

> (303) 433-0905 Fax

> Member AFCCE

>

>

> -----Original Message-----

> From: sbe-bounces at sbe.org [mailto:sbe-bounces at sbe.org] On Behalf Of Tim

> Kelly

> Sent: Sunday, February 17, 2008 7:34 AM

> To: sbe at sbe.org

> Subject: Re: [SBE] SBE Digest, Vol 30, Issue 6

>

> Put roofing tar on the exposed copper. If it is not shiny bright it is not

> worth the crooks time. They have to clean it off and they do not receive

> the

> same amount of money if it is on there.

>

>

> -----Original Message-----

> From: sbe-bounces at sbe.org [mailto:sbe-bounces at sbe.org] On Behalf Of

> sbe-request at sbe.org

> Sent: Sunday, February 17, 2008 12:07 AM

> To: sbe at sbe.org

> Subject: SBE Digest, Vol 30, Issue 6

>

> Send SBE mailing list submissions to

> sbe at sbe.org

>

> To subscribe or unsubscribe via the World Wide Web, visit

> http://seven.pairlist.net/mailman/listinfo/sbe

> or, via email, send a message with subject or body 'help' to

> sbe-request at sbe.org

>

> You can reach the person managing the list at

> sbe-owner at sbe.org

>

> When replying, please edit your Subject line so it is more specific than

> "Re: Contents of SBE digest..."

>

>

> SBE Roundtable

>

> Today's Topics:

>

>   1. Re: conversation topic: how often do you check tower ground

>      (Mike Langner)

>   2. Friendly Neighbors (chscherer at everestkc.net)

>   3. Can you think of a broadcast example? Another conversation

>      topic. (A9xw at cs.com)

>   4. ACR Cassette? (Funk, Andrew R)

>   5. Re: conversation topic: how often do you check tower ground

>      (Ron Baker)

>

>

> ----------------------------------------------------------------------

>

> Message: 1

> Date: Sat, 16 Feb 2008 08:03:05 -0700

> From: "Mike Langner" <mlangner at swcp.com>

> Subject: Re: [SBE] conversation topic: how often do you check tower

> ground

> To: "sbe member discussion mail list" <sbe at sbe.org>

> Message-ID: <EJEGJKKADOAJPODEOBDHAEFNCHAA.mlangner at swcp.com>

> Content-Type: text/plain; charset="us-ascii"

>

> Years ago at two of the AM stations I used to take care of we had tenants

> either in an apartment attached to the transmitter building or in an

> apartment immediately adjacent to the transmitter building. In one site

> employees got free or close to free rent for watching out for our copper,

> in

> the other we simply rented the modest single family dwelling for a low

> rate

> with the understanding that the tenant had "lookout" duties. In both cases

> we had no problems during the times there was a frequent presence on the

> property.  Of course, the price of copper was lower in those days.

>

> How crazy is life?  In the case of the single family detached dwelling,

> upon

> a vacancy, the station owner's son announced that he was going to live in

> the little house.  His father announced that, "No, he wasn't!" and sent a

> crane with a wrecking ball to cave in the roof.  The rest of the house was

> removed a month or so later. Copper then began to be removed, too!

>

> That owner was a colorful part of New Mexico broadcasting history.  Some

> day

> someone will write a book.  It'll contain other episodes, like the time he

> drove to California, flew back, couldn't find his car in the parking lot,

> and reported it stolen.

>

> Or the time he and his wife flew back from New York via O'Hare with their

> kids.  Except that from O'Hare they had to take separate flights due to

> airline congestion and sold-out planes.  When he and his wife met at the

> baggage claim here, she asked where the kids were.  He'd forgotten about

> them, and left them in the Chicago airport.

>

> And that's just the beginning!  (But it's more than enough for now!)

>

> So back to copper -- in my opinion, a human presence is the only

> reasonable

> thing that'll work.  You know the saying, if you build a 20 foot fence,

> they'll get a 21 foot ladder. . .

>

> Good luck to all!

>

> Mike Langner

> Albuquerque, NM

> _________________________

>

>

> -----Original Message-----

> From: sbe-bounces at sbe.org [mailto:sbe-bounces at sbe.org]On Behalf Of

> dynotherm at earthlink.net

> Sent: Saturday, February 16, 2008 1:14 AM

> To: sbe member discussion mail list

> Subject: Re: [SBE] conversation topic: how often do you check tower ground

>

>

> In that case, perhaps you should consider inspection at 30 minute

> intervals

> like the old days of Tx logging.

> No, on second thought, even that may not be enough. ;-)

>

> --------------------------

> Phil Alexander, CSRE , AMD

> Broadcast Engineering Services and Technology (a Div. of Advanced Parts

> Corporation)

> Ph. (317) 335-2065   FAX (317) 335-9037

>

>

> -----Original Message-----

>>From: Mike Langner <mlangner at swcp.com>

>>Sent: Feb 15, 2008 10:11 PM

>>To: sbe member discussion mail list <sbe at sbe.org>

>>Subject: Re: [SBE] conversation topic: how often do you check tower

>>ground

>>

>>Please understand that in my case frequently checking the ground system

>>is not so much based on chemistry as much as it's based on copper theft!!

>>

>>Mike Langner

>>Albuquerque, NM

>>___________________

>>

>>

>>-----Original Message-----

>>From: sbe-bounces at sbe.org [mailto:sbe-bounces at sbe.org]On Behalf Of

>>Barry Thomas, CPBE CBNT

>>Sent: Friday, February 15, 2008 8:00 PM

>>To: dynotherm at earthlink.net; Member Discussion List

>>Subject: Re: [SBE] conversation topic: how often do you check tower

>>ground

>>

>>

>>Items like this is why the SBE list is such a great resource. Thanks

>>for a comprehensive treatment, Phil.

>>

>>

>>Sent from my Verizon Wireless BlackBerry

>>

>>-----Original Message-----

>>From: dynotherm at earthlink.net

>>

>>Date: Fri, 15 Feb 2008 21:33:01 -0500 (GMT-05:00) To:barryt at sbe.org,

>>sbe member discussion mail list <sbe at sbe.org>

>>Subject: Re: [SBE] conversation topic: how often do you check tower

>>ground

>>

>>

>>While the systems are separate, they have the effect of the soil on

>>copper in common, thus, to an extent, the deterioration of all buried

>>copper will be somewhat similar.

>>

>>If the lightning dissipation/mitigation system is combined with the RF

>>ground as may frequently be the case at the tower base(s), the

>>condition of the gaps and the lower gap connection to the common ring

>>tie is generally indicative of damage, however, careful examination of

>>the ATU components is also critical in this event. Not only can a

>>strike blow capacitors, it can reform coils, sometimes in a spectacular

>>way.

>>

>>The corrosion life of buried copper varies widely as it is essentially

>>a function of soil chemistry. I have seen radial systems 60 years old

>>where the finish of the wire had only evolved from bright copper to

>>heavy brown (CuO) patina. OTOH I have a very few systems turning

>>brittle blue in less than ten years.

>>

>>The difference can usually be found by looking at soil pH, chloride,

>>nitrate and ammonium content. When a new system is put into cropland

>>care should be taken to bring the pH into the mildly alkaline range. If

>>the soil has been heavily fertilized, a small sample plot of 1/4 to 1/2

>>acre should be ripped, deeply plowed, pH adjusted (generally by liming)

>>and analyzed again a little below the burial depth.

>>

>>If ammonium or chloride radicals remain present in excessive amounts,

>>it should be understood that the radial system will be a high

>>maintenance item requiring annual inspection. At this point it may be

>>wise to consider an alternative site or elevated counterpoise.

>>

>>If the test plot treatment shows an acceptable result the entire area

>>should be conditioned in the same way before burying copper (or other

>>metals).

>>

>>However, most sites in inland areas such as unfertilized pasture or

>>grazing land or adequately conditioned cropland may not require

>>replacement literally for generations.

>>

>>One clue pointing to possible ground system deterioration is an

>>appearance of base current drift with changing soil moisture

>>conditions. Another is an apparent long term shift in base impedance.

>>In both cases, the ground system is suspect, however the tower(s) may

>>be the cause if not well bonded at section joints (usually by tack

>>welding). If either of these conditions appears, the tower(s) should be

>>checked and bonded if this has not been previously done.

>>

>>If the condition persists, radials can be checked using a "sniffer"

>>coil as the external antenna of a FIM. This is simply a loop coil of

>>several turns 4 to 6 inches in diameter mounted on the end of a

>>broomstick connected with about 6 feet of RG-58 and a BNC connector to

>>the FIM's external input.

>>Moving the "sniffer" over the ground about 45 degrees out from the

>>tower and comparing results over each radial will clearly show low

>>induced current in bad radials. One caution is that this process can

>>show a false good reading when a radial is broken near the tower. If

>>broken radials are found, it is wise to check radials by other means

>>such as end to end resistance at adjacent outer ends, or with a

>>clamp-on RFA such as was described earlier in this thread.

>>

>>Unless there is traffic over the radial system on unimproved roads or

>>paths, or cattle graze the site, it is unnecessary to check the radials

>>of a system in good soil more often than every five or ten years unless

>>abnormal operation is suspected.

>>

>>However, if the soil conditions are poor, annual inspections should be

>>scheduled. The inspection should be electrical, as above, for broken

>>radials, and mechanical for visible signs of corrosion by digging up

>>the ends of a few radials selected at random and visually observing

>>their condition. Visually, good wire will be flexible, not brittle, and

>>brown, not blue-green. Cleaning with sandpaper or steel wool should

>>reveal uniform, unpitted, bright copper. Pitting, bluish color or

>>brittle conditions are all indicators of deterioration or failure,

>>however the system will have a degree of function as long as a low

>>resistance metallic path remains.

>>

>>Where cattle graze over a ground system, or where farming or other

>>vehicles travel over the system on unimproved paths, annual inspection

>>for broken radials in the affected areas is essential and consideration

>>to deeper than normal burial should be considered.

>>

>>Ground systems and their performance in transmission systems are one of

>>the topics we cover in the Radio Guide AM Transmission Seminars.

>>

>>--------------------------

>>Phil Alexander, CSRE , AMD

>>Broadcast Engineering Services and Technology (a Div. of Advanced Parts

>>Corporation)

>>Ph. (317) 335-2065   FAX (317) 335-9037

>>

>>

>>

>>-----Original Message-----

>>>From: Barry Thomas, CPBE CBNT <barryt at sbe.org>

>>>Sent: Feb 14, 2008 2:22 PM

>>>To: A9xw at cs.com, Barry Thomas <barryt at sbe.org>, Member Discussion List

>><SBE at sbe.org>

>>>Subject: Re: [SBE] conversation topic: how often do you check tower

>>>ground

>>>

>>>The two systems would have different characteristics and purposes and

>>>therefore different inspection schedules and procedures.

>>>

>>>For electrical and lightning grounds, they should be inspected after

>>>every known electrical event. I used to physically check during weekly

>>>transmitter inspections. I've usually not done a more indepth analysis

>>>unless there is an increase in storm or electrical damage.

>>>

>>>For antenna radials. The system performance usually degrades which

>>>will initiate inspection but I typically do a full inspection every

>>>2-3 years if the antenna system is stable.

>>>

>>>Sent from my Verizon Wireless BlackBerry

>>>

>>>-----Original Message-----

>>>From: A9xw at cs.com

>>>

>>>Date: Thu, 14 Feb 2008 13:12:38

>>>To:barryt at sbe.org

>>>Subject: Re: [SBE] conversation topic: how often do you check tower

>>>ground

>>>

>>>

>>>We're discussing ground system life, how often to check, maintenance

>>>intervals, etc. Both radial and rods.

>>>

>>> Henry

>>

>>_______________________________________________

>>SBE mailing list

>>To unsubscribe, go to http://seven.pairlist.net/mailman/options/sbe

>>_______________________________________________

>>SBE at sbe.org

>>http://seven.pairlist.net/mailman/listinfo/sbe

>>

>>

>>

>>_______________________________________________

>>SBE mailing list

>>To unsubscribe, go to http://seven.pairlist.net/mailman/options/sbe

>>_______________________________________________

>>SBE at sbe.org

>>http://seven.pairlist.net/mailman/listinfo/sbe

>

> _______________________________________________

> SBE mailing list

> To unsubscribe, go to http://seven.pairlist.net/mailman/options/sbe

> _______________________________________________

> SBE at sbe.org

> http://seven.pairlist.net/mailman/listinfo/sbe

>

>

>

>

>

> ------------------------------

>

> Message: 2

> Date: Sat, 16 Feb 2008 09:23:11 -0600

> From: chscherer at everestkc.net

> Subject: [SBE] Friendly Neighbors

> To: sbe member discussion mail list <sbe at sbe.org>

> Message-ID: <f5b1b9337f2b.47b6ab7f at everestkc.net>

> Content-Type: text/plain; charset=us-ascii

>

> I agree with Mike that a human presence is hard to beat if it's available.

> At my transmitter sites that were near or in a residential area, I would

> always try to meet the neighbors. Most of the time they were happy to

> report

> any strange activity.

>

> At one site, the local police liked to use the long driveway as secluded

> spot to complete their reports before their shifts ended. I would always

> talk to them when they were there.

>

> ----- Original Message -----

> From: Mike Langner <mlangner at swcp.com>

>> Years ago at two of the AM stations I used to take care of we had

>> tenantseither in an apartment attached to the transmitter building or

>> in an apartment immediately adjacent to the transmitter building.

> ...

>

>

> ------------------------------

>

> Message: 3

> Date: Sat, 16 Feb 2008 13:11:35 EST

> From: A9xw at cs.com

> Subject: [SBE] Can you think of a broadcast example? Another

> conversation topic.

> To: sbe at sbe.org

> Message-ID: <cdd.23718102.34e88157 at cs.com>

> Content-Type: text/plain; charset="US-ASCII"

>

> I train dogs at our kennel when not training employees they need to do

> more

> than push buttons.

>

> Animal control. Teaching sit-stay.

> 1.  Dog sits. you toss the toy, (fetch) let the dog run after it and bring

> it back.

> 2.  Dog sits. You toss the toy, but make the dog wait a while then

> "fetch".

> 3.  Dog sits. You heel the dog to the toy and let them take it.

> 4.  Dog sits. You tell it stay, walk over, get the toy and bring it back.

>

> Which style manager are you and why?

>

> Henry Ruhwiedel

> WYIN, AA9XW, K9ATN   </HTML>

>

>

> ------------------------------

>

> Message: 4

> Date: Sat, 16 Feb 2008 18:46:49 +0000

> From: "Funk, Andrew R" <Andrew.R.Funk at abc.com>

> Subject: [SBE] ACR Cassette?

> To: "sbe member discussion mail list" <sbe at sbe.org>

> Message-ID: <a12201c870cc$431ec40d$25b00699 at wdw.disney.com>

> Content-Type: text/plain; charset="utf-8"

>

> Back in the day I operated both TCRs and ACRs.  I have an old TCR cart in

> my

> collection, but I don't have an ACR cassette.   By any chance does someone

> on the list have an extra ACR cassette they would be willing to part with?

>

> Thanks,

>

> /Andy

>

> --

> Andy Funk

> [sent from my mobile phone]

>

>

> -----Original Message-----

> From: "A9xw at cs.com" <A9xw at cs.com>

> To: "sbe at sbe.org" <sbe at sbe.org>

> Sent: 2/16/2008 12:11 PM

> Subject: [SBE] Can you think of a broadcast example? Another

> conversationtopic.

>

> I train dogs at our kennel when not training employees they need to do

> more

> than push buttons.

>

> Animal control. Teaching sit-stay.

> 1.  Dog sits. you toss the toy, (fetch) let the dog run after it and bring

> it back.

> 2.  Dog sits. You toss the toy, but make the dog wait a while then

> "fetch".

> 3.  Dog sits. You heel the dog to the toy and let them take it.

> 4.  Dog sits. You tell it stay, walk over, get the toy and bring it back.

>

> Which style manager are you and why?

>

> Henry Ruhwiedel

> WYIN, AA9XW, K9ATN   </HTML>

> _______________________________________________

> SBE mailing list

> To unsubscribe, go to http://seven.pairlist.net/mailman/options/sbe

> _______________________________________________

> SBE at sbe.org

> http://seven.pairlist.net/mailman/listinfo/sbe

>

>

> ------------------------------

>

> Message: 5

> Date: Sat, 16 Feb 2008 21:06:45 -0800

> From: "Ron Baker" <ronbaker.ron at gmail.com>

> Subject: Re: [SBE] conversation topic: how often do you check tower

> ground

> To: barryt at sbe.org, "sbe member discussion mail list" <sbe at sbe.org>

> Message-ID:

> <aae0b99c0802162106q399728adje56d82ec8eb3dcd8 at mail.gmail.com>

> Content-Type: text/plain; charset=ISO-8859-1

>

> When is the Radio Guide AM Transmission Seminar scheduled for the west

> coast?

>

> On 2/15/08, Barry Thomas, CPBE CBNT <barryt at sbe.org> wrote:

>>

>> Items like this is why the SBE list is such a great resource. Thanks

>> for a comprehensive treatment, Phil.

>>

>>

>> Sent from my Verizon Wireless BlackBerry

>>

>> -----Original Message-----

>> From: dynotherm at earthlink.net

>>

>> Date: Fri, 15 Feb 2008 21:33:01 -0500 (GMT-05:00) To:barryt at sbe.org,

>> sbe member discussion mail list <sbe at sbe.org>

>> Subject: Re: [SBE] conversation topic: how often do you check tower

>> ground

>>

>>

>> While the systems are separate, they have the effect of the soil on

>> copper in common, thus, to an extent, the deterioration of all buried

>> copper will be somewhat similar.

>>

>> If the lightning dissipation/mitigation system is combined with the RF

>> ground as may frequently be the case at the tower base(s), the

>> condition of the gaps and the lower gap connection to the common ring

>> tie is generally indicative of damage, however, careful examination of

>> the ATU components is also critical in this event. Not only can a

>> strike blow capacitors, it can reform coils, sometimes in a

>> spectacular way.

>>

>> The corrosion life of buried copper varies widely as it is essentially

>> a function of soil chemistry. I have seen radial systems 60 years old

>> where the finish of the wire had only evolved from bright copper to

>> heavy brown (CuO) patina. OTOH I have a very few systems turning

>> brittle blue in less than ten years.

>>

>> The difference can usually be found by looking at soil pH, chloride,

>> nitrate and ammonium content. When a new system is put into cropland

>> care should be taken to bring the pH into the mildly alkaline range.

>> If the soil has been heavily fertilized, a small sample plot of 1/4 to

>> 1/2 acre should be ripped, deeply plowed, pH adjusted (generally by

>> liming) and analyzed again a little below the burial depth.

>>

>> If ammonium or chloride radicals remain present in excessive amounts,

>> it should be understood that the radial system will be a high

>> maintenance item requiring annual inspection. At this point it may be

>> wise to consider an alternative site or elevated counterpoise.

>>

>> If the test plot treatment shows an acceptable result the entire area

>> should be conditioned in the same way before burying copper (or other

>> metals).

>>

>> However, most sites in inland areas such as unfertilized pasture or

>> grazing land or adequately conditioned cropland may not require

>> replacement literally for generations.

>>

>> One clue pointing to possible ground system deterioration is an

>> appearance of base current drift with changing soil moisture

>> conditions. Another is an apparent long term shift in base impedance.

>> In both cases, the ground system is suspect, however the tower(s) may

>> be the cause if not well bonded at section joints (usually by tack

>> welding). If either of these conditions appears, the tower(s) should

>> be checked and bonded if this has not been previously done.

>>

>> If the condition persists, radials can be checked using a "sniffer"

>> coil as the external antenna of a FIM. This is simply a loop coil of

>> several turns 4 to 6 inches in diameter mounted on the end of a

>> broomstick connected with about 6 feet of RG-58 and a BNC connector to

>> the FIM's external input.

>> Moving the "sniffer" over the ground about 45 degrees out from the

>> tower and comparing results over each radial will clearly show low

>> induced current in bad radials. One caution is that this process can

>> show a false good reading when a radial is broken near the tower. If

>> broken radials are found, it is wise to check radials by other means

>> such as end to end resistance at adjacent outer ends, or with a

>> clamp-on RFA such as was described earlier in this thread.

>>

>> Unless there is traffic over the radial system on unimproved roads or

>> paths, or cattle graze the site, it is unnecessary to check the

>> radials of a system in good soil more often than every five or ten

>> years unless abnormal operation is suspected.

>>

>> However, if the soil conditions are poor, annual inspections should be

>> scheduled. The inspection should be electrical, as above, for broken

>> radials, and mechanical for visible signs of corrosion by digging up

>> the ends of a few radials selected at random and visually observing

>> their condition. Visually, good wire will be flexible, not brittle,

>> and brown, not blue-green. Cleaning with sandpaper or steel wool

>> should reveal uniform, unpitted, bright copper. Pitting, bluish color

>> or brittle conditions are all indicators of deterioration or failure,

>> however the system will have a degree of function as long as a low

>> resistance metallic path remains.

>>

>> Where cattle graze over a ground system, or where farming or other

>> vehicles travel over the system on unimproved paths, annual inspection

>> for broken radials in the affected areas is essential and

>> consideration to deeper than normal burial should be considered.

>>

>> Ground systems and their performance in transmission systems are one

>> of the topics we cover in the Radio Guide AM Transmission Seminars.

>>

>> --------------------------

>> Phil Alexander, CSRE , AMD

>> Broadcast Engineering Services and Technology (a Div. of Advanced

>> Parts Corporation)

>> Ph. (317) 335-2065   FAX (317) 335-9037

>>

>>

>>

>> -----Original Message-----

>> >From: Barry Thomas, CPBE CBNT <barryt at sbe.org>

>> >Sent: Feb 14, 2008 2:22 PM

>> >To: A9xw at cs.com, Barry Thomas <barryt at sbe.org>, Member Discussion

>> >List <

>> SBE at sbe.org>

>> >Subject: Re: [SBE] conversation topic: how often do you check tower

>> >ground

>> >

>> >The two systems would have different characteristics and purposes and

>> >therefore different inspection schedules and procedures.

>> >

>> >For electrical and lightning grounds, they should be inspected after

>> >every known electrical event. I used to physically check during

>> >weekly transmitter inspections. I've usually not done a more indepth

>> >analysis unless there is an increase in storm or electrical damage.

>> >

>> >For antenna radials. The system performance usually degrades which

>> >will initiate inspection but I typically do a full inspection every

>> >2-3 years if the antenna system is stable.

>> >

>> >Sent from my Verizon Wireless BlackBerry

>> >

>> >-----Original Message-----

>> >From: A9xw at cs.com

>> >

>> >Date: Thu, 14 Feb 2008 13:12:38

>> >To:barryt at sbe.org

>> >Subject: Re: [SBE] conversation topic: how often do you check tower

>> >ground

>> >

>> >

>> >We're discussing ground system life, how often to check, maintenance

>> >intervals, etc. Both radial and rods.

>> >

>> > Henry

>>

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>

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