someone tried to feed a type g5rv antenna with ´european´ zip-cord ?
(european meaning double the Volts compared to USA, thus half amps
for the same lamp wattage)
Would yield a simple ant, peel the first say abt 15- 17 meters, splitting
them up to the dipole part and the the rest X meter to a balanced tuner etc.
sorry if this has been up too many times, search did´nt give a clue!

Tnx for info, 73 Per / sm7aha malmo, sweden

On Tue, 12 Jul 2005 20:44:33 GMT, "pegge"
wrote:
someone tried to feed a type g5rv antenna with ´european´ zip-cord ?
Would yield a simple ant, peel the first say abt 15- 17 meters, splitting
them up to the dipole part and the the rest X meter to a balanced tuner etc.

Hi Per,

Hard to apply the name g5rv to this, but that makes no difference
anyway. Simply call it a dipole driven with close spaced twin lead.
That twin lead will be 50 to 70 Ohms characteristic impedance. It
will also have a suspect dielectric loss. This does not make it a bad
antenna. There will be the usual high loss with high SWR - depending
upon the gauge of the wire.

In short, no worse than an ordinary antenna used outside of its
natural resonance.

73's
Richard Clark, KB7QHC

"pegge" wrote in message
...
someone tried to feed a type g5rv antenna with ´european´ zip-cord ?
(european meaning double the Volts compared to USA, thus half amps
for the same lamp wattage)
Would yield a simple ant, peel the first say abt 15- 17 meters, splitting
them up to the dipole part and the the rest X meter to a balanced tuner
etc.
sorry if this has been up too many times, search did´nt give a clue!

Tnx for info, 73 Per / sm7aha malmo, sweden

Check out the following analysis:

http://www.vk1od.net/G5RV/index.htm

Frank

I had thought about it because I had a 500 ft roll on hand at the time - but
changed my mind because research showed zip cord to be high-loss

"pegge" wrote in message
...
someone tried to feed a type g5rv antenna with ´european´ zip-cord ?
(european meaning double the Volts compared to USA, thus half amps
for the same lamp wattage)
Would yield a simple ant, peel the first say abt 15- 17 meters, splitting
them up to the dipole part and the the rest X meter to a balanced tuner
etc.
sorry if this has been up too many times, search did´nt give a clue!

Tnx for info, 73 Per / sm7aha malmo, sweden

Hal Rosser wrote:
I had thought about it because I had a 500 ft roll on hand at the time - but
changed my mind because research showed zip cord to be high-loss

"pegge" wrote in message
...

someone tried to feed a type g5rv antenna with ´european´ zip-cord ?
(european meaning double the Volts compared to USA, thus half amps
for the same lamp wattage)
Would yield a simple ant, peel the first say abt 15- 17 meters, splitting
them up to the dipole part and the the rest X meter to a balanced tuner

etc.

sorry if this has been up too many times, search did´nt give a clue!

Tnx for info, 73 Per / sm7aha malmo, sweden





Go for it. I've seen a dipole fed by electric blasting wire. Worked fine.

Dave N WD9BDZ

I have a 40meter band xmit/recv antenna up with good swr and works great.
Cost me nothing but my time, and a plastic center insulator to strain
releive the zip cord (rather than tie a knot in the cord at the center. Just
rip down 33 ft of zip cord, tie a knot or use the insulator, and cut the
feedlinne section to a integral half wave long (20, 40, 60etc meters long).
If cut to a half wave (use a dip meter) the swr of the dipole will be
translated unaltered to the radio end of your feedline and 70 ohms is OK for
a swr of 1.4 and the xcvr will not care usually.

Great emergency antenna.



"pegge" wrote in message
...
someone tried to feed a type g5rv antenna with ´european´ zip-cord ?
(european meaning double the Volts compared to USA, thus half amps
for the same lamp wattage)
Would yield a simple ant, peel the first say abt 15- 17 meters, splitting
them up to the dipole part and the the rest X meter to a balanced tuner
etc.
sorry if this has been up too many times, search did´nt give a clue!

Tnx for info, 73 Per / sm7aha malmo, sweden

"tjs" wrote in message ...
I have a 40meter band xmit/recv antenna up with good swr and works great.
Cost me nothing but my time, and a plastic center insulator to strain
releive the zip cord (rather than tie a knot in the cord at the center. Just
rip down 33 ft of zip cord, tie a knot or use the insulator, and cut the
feedlinne section to a integral half wave long (20, 40, 60etc meters long).
If cut to a half wave (use a dip meter) the swr of the dipole will be
translated unaltered to the radio end of your feedline and 70 ohms is OK for
a swr of 1.4 and the xcvr will not care usually.

Great emergency antenna.

Why do you think the SWR of the dipole will be unaltered at the radio end of the feedline? You are apparently ignoring the loss in the line that makes the SWR at the radio end less than that at the dipole terminals.

If the zip cord had zero loss the SWR would be the same everywhere along the line, only the terminal impedance at the radio end would be the same as at the dipole.

Without knowing the vf (velocity factor) of the zip cord how do you determine that the length is a half wave?

And last, why would you want the length to be a half wave?

Walt, W2DU


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

On Wed, 13 Jul 2005 13:50:03 -0400, "Walter Maxwell"
wrote:

This is a multi-part message in MIME format.
Why? Because you are using that POS Outlook Express again! :-(

Why do you think the SWR of the dipole will be unaltered at the radio =
end of the feedline? You are apparently ignoring the loss in the line =
that makes the SWR at the radio end less than that at the dipole =
terminals.

If the zip cord had zero loss the SWR would be the same everywhere =
along the line, only the terminal impedance at the radio end would be =
the same as at the dipole.

Without knowing the vf (velocity factor) of the zip cord how do you =
determine that the length is a half wave?

And last, why would you want the length to be a half wave?=20

Walt, W2DU

And your posting mentions nothing in it that suggests why there is a
GIF attachment which may be infected.

Walt,

This is like running full power deliberately into a 10:1 mismatch:
15 lines of content does not warrant a 156 line posting.

73's
Richard Clark, KB7QHC

Walter Maxwell wrote:


Richard, I can't imagine why you'd see a 156 line posting. I deleted
everything except 12 lines above my posting. And 12 are all that come up
when I review my post. Something musta happened that I'm not aware of.

However, I will confess that I overlooked a GIF attachment. I have never
claimed that I could go through an entire day without screwing something up.

Walt

Walt

Both this post and your previous one look fine on Mozilla; no huge
number of lines. A file called p.gif is coming along with it, though.

tom
K0TAR

"Walter Maxwell" wrote in message
...

"tjs" wrote in message ...
I have a 40meter band xmit/recv antenna up with good swr and works great.
Cost me nothing but my time, and a plastic center insulator to strain
releive the zip cord (rather than tie a knot in the cord at the center.
Just
rip down 33 ft of zip cord, tie a knot or use the insulator, and cut the
feedlinne section to a integral half wave long (20, 40, 60etc meters
long).
If cut to a half wave (use a dip meter) the swr of the dipole will be
translated unaltered to the radio end of your feedline and 70 ohms is OK
for
a swr of 1.4 and the xcvr will not care usually.

Great emergency antenna.

Why do you think the SWR of the dipole will be unaltered at the radio end
of the feedline? You are apparently ignoring the loss in the line that
makes the SWR at the radio end less than that at the dipole terminals.

If the zip cord had zero loss the SWR would be the same everywhere along
the line, only the terminal impedance at the radio end would be the same
as at the dipole.

Without knowing the vf (velocity factor) of the zip cord how do you
determine that the length is a half wave?

And last, why would you want the length to be a half wave?

Walt, W2DU

I think he was correct about the half-wave length of feedline:
according to the ARRL Antenna Book - 17th edition copyright 1994 - page
24-12 in chapter 24, under the Heading "Special Cases" and under the
sub-heading "The Half-WaveLength Line", it pretty clearly states that
regardless of z, it will be the same on both ends of a half-wave line. and
sections having such length can be added or removed without changing the
load Z. (as long as loss is negligible)

Also - You don't need to know the VF if you use a dip meter (or MFJ 259) -
And he would want the length to be half-wave so as to be able to ignore the
characteristic impedence of the zip line and deal directly with the
impedence of the dipole directly.