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"Reg Edwards" wrote

To calculate change in velocity due to plastic PVC insulation we
need
to know :-

Wire diameter = d
Diameter over insulation = D
Height of wire above ground = H
Permittivity of insulating material = K

First calculate capacitance of bare wire to ground.
Then calculate capacitance of insulated wire to ground.
Velocity Factor = SquareRoot of their ratio.
Neither Terman's nor Kraus' Bibles will mention the following
formulae. So you'll just have to take my word for it.


Velocity Factor = SquareRoot( ( A + B ) / C )

Where -

A = K * Ln( 4 * H / D )

B = Ln( D / d )

C = K * Ln( 4 * H / d )

Example :
Bare wire diameter = 1.6 mm = 14 awg.
Diameter over insulation = 2.6 mm.
Height above ground = 10 metres = 33 feet.
Permittivity of insulation = 3.5

Velocity factor = 0.983
Or a decrease in resonant frequency of 1.7 percent which can nearly
always be forgotten about.

The electrical effect of the enamel on magnet wire is entirely
negligible. But it does protect the wire from atmospheric pollution.

========================================

After a couple of days, and the time it took to derive the equations,
does nobody want to argue about it ? What about you, my dear Richard
Clark ?

By the way, I have now reverted to Australian, Banrock Station red
plonk as being the best buy in my local supermarket. To get into my
glass it has to come 12,000 miles. But, like it or not, our small
globe gets smaller day by day.
----
Reg, G4FGQ.

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On Sat, 29 Oct 2005 22:31:04 +0000 (UTC), "Reg Edwards"
wrote:
does nobody want to argue about it ? What about you, my dear Richard Clark ?
By the way, I have now reverted to Australian, Banrock Station red

I've been drinking "Tango" labels from Argentina. Wanna step out into
the parking lot to talk about this?

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On 2005-10-29, Reg Edwards wrote:
By the way, I have now reverted to Australian, Banrock Station red

Yellow Tail Shiraz

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"Richard Clark" wrote -

Wanna step out into
the parking lot to talk about this?

===================================

A typical USA aggresive attitude towards foreigners. ;o)

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What da ya mean by that, you want me to kick your limey ass...

"Reg Edwards" wrote in message
...
===================================

A typical USA aggresive attitude towards foreigners. ;o)

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Reg Edwards wrote:
"Richard Clark" wrote -
Wanna step out into
the parking lot to talk about this?

A typical USA aggresive attitude towards foreigners. ;o)

That's also a pick up line, Reg. :-)
--
73, Cecil http://www.qsl.net/w5dxp

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On Sun, 30 Oct 2005 20:50:17 GMT, Cecil Moore wrote:

Reg Edwards wrote:
"Richard Clark" wrote -
Wanna step out into
the parking lot to talk about this?

A typical USA aggresive attitude towards foreigners. ;o)

That's also a pick up line, Reg. :-)

Cecil, I don't know whether these guys want to step into the parking
lot to trade kicks to the groin, or to smooch... but neither is too
edifying!

Owen
--

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Reg Edwards wrote:

A typical USA aggresive attitude towards foreigners. ;o)


I hope none of the readers of this newsgroup are tempted to consider
Reg's attitude or abrasiveness as typical of his countrymen. I recently
returned from three weeks in Great Britain, ranging from southern
England to the Isle of Skye in Scotland, and to southern and central
Wales. Like on my previous three trips there, I was treated very well by
some of the nicest people I know and have met. I, my wife, and son were
taken in as house guests by two very good friends in different parts of
the country.

I'm sure that if I'd displayed the sort of attitude toward the British
that Reg constantly does toward Americans, I would have had an entirely
different experience. But I'd rather concentrate on what good people
have in common. And there are a lot of good people in all countries. As
well as a few grumps, of course.

Roy Lewallen, W7EL

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Roy, I have to second your opinion. The last time the wife and I were in
Europe, we were standing in the airport in Frankfurt heading to Italy, we
both at the same time said "Let's go back to England".

We like to stay at the Bull in Gerrard's Cross and find the people are
wonderful. I was readily accepted into the Denham flying club and enjoyed
touring England via private plane. The huge chalk carvings south of London
can only be appreciated from the air.

I picture Reg as an old socialist that time has passed by, and he has since
decided to become a professional curmudgeon. He does provide humor from time
to time. We must always remember - Everyone has a purpose in life, even if
it is only as a bad example -.

I think of him every time I see the brother-in-law on "Keeping Up
Appearances" on the BBC.

"Roy Lewallen" wrote in message
...
Reg Edwards wrote:

A typical USA aggresive attitude towards foreigners. ;o)


I hope none of the readers of this newsgroup are tempted to consider
Reg's attitude or abrasiveness as typical of his countrymen. I recently
returned from three weeks in Great Britain, ranging from southern
England to the Isle of Skye in Scotland, and to southern and central
Wales. Like on my previous three trips there, I was treated very well by
some of the nicest people I know and have met. I, my wife, and son were
taken in as house guests by two very good friends in different parts of
the country.

I'm sure that if I'd displayed the sort of attitude toward the British
that Reg constantly does toward Americans, I would have had an entirely
different experience. But I'd rather concentrate on what good people
have in common. And there are a lot of good people in all countries. As
well as a few grumps, of course.

Roy Lewallen, W7EL

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On Sun, 30 Oct 2005 17:53:45 -0500, "Fred W4JLE"
wrote:

I think of him every time I see the brother-in-law on "Keeping Up
Appearances" on the BBC.

Don't you feel that's a bit complimentary whats-his-name and a bit
derogatory to the brother-in-law.

Danny, K6MHE

email: k6mheatarrldotnet
http://www.k6mhe.com/