Well, the copper thickness does make a difference at low HF frequencies as
RF penetrates deeper than it does at higher frequencies and can get down to
the steel and losses go up.
A very thin copper coating can work better at higher frequencies than at low
frequencies because of the depth of penetration.
I am trying to figure out how to measure this particular type of wire's
worth at low HF. Not knowing the thickness of the copper plating.
It seems that there should be a way to measure this electrically.
73
Gary K4FMX
> -----Original Message-----
> From: TowerTalk [mailto:towertalk-bounces@contesting.com] On Behalf Of
> Kevin Kidd
> Sent: Friday, August 08, 2014 4:38 PM
> Cc: reflector Towertalk
> Subject: Re: [TowerTalk] Copper clad telephone wire
>
> You are absolutely correct. Cutting copper clad wire with shears
> "smears"
> the copper down the steel.
>
> Cut it normally and then take a file or fine grinding wheel and grind it
> down flat. You should see a very clear demarcation between the copper
> and
> steel.
>
> We use some copper clad in broadcast grounding and have had people often
> think that it was solid due to the "smearing".
>
> On another note... Unless the copper is very, very, very thin (as in a
> plating), it won't make any measurable difference at HF how thick the
> copper is since most RF travels on the surface within the first few skin
> depths. A skin depth at HF frequencies is just a couple thousandths of
> an
> inch depending on freq. The copper clad (CopperWeld) that we use has
> several skin depths of copper even at AM Broadcast frequencies.
>
> Good luck,
>
> On Fri, Aug 8, 2014 at 4:11 PM, Dave Hachadorian <k6ll.dave@gmail.com>
> wrote:
>
> > Maybe when you cut it, the copper mashed down so you couldn't see the
> > steel core. Try scraping off the copper with a knife. Measure the
> diameter
> > before and after with a micrometer or even a machinist's ruler.
>
>
>
>
> Kevin C. Kidd, CSRE/AMD
> AM Ground Systems Company - WD4RAT
> kkidd@kkbc.com -- 866-22-RADIO -- 866-227-2346
> www.amgroundsystems.com
> _______________________________________________
>
>
>
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