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Reg Edwards December 14th 03 12:48 AM

Download program DIPCAGE2 from website below.
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Regards from Reg, G4FGQ
For Free Radio Design Software go to
http://www.btinternet.com/~g4fgq.regp
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Could you suggest any values of what one could expect to find for
radiiation resistance for some variations of half wave dipoles,
dependent on wire size, height and other?




Rich Grise December 14th 03 02:10 AM

I remember as WN0GJS tuning the pi-net output to a piece of
300-ohm twin-lead thru a PL-259!

So make a little amp. with a pi output, tune it up, and
measure the components.

Since I learned this kind of stuff only in the school
of hard-knox, I refer to it as the "empirical" method. ;-)

Cheers!
Rich

Paul Burridge wrote:

I'm simply trying to establish the radiation resistance of a non-ideal
antenna so I can reasonably match it to the output impedance of the
transmitter PA stage. The figure is likely to be very low, given that
this antenna is highly non-ideal. I'm not interested in plotting polar
patterns of the radiation distribution!
--

"I expect history will be kind to me, since I intend to write it."
- Winston Churchill


Rich Grise December 14th 03 02:10 AM

I remember as WN0GJS tuning the pi-net output to a piece of
300-ohm twin-lead thru a PL-259!

So make a little amp. with a pi output, tune it up, and
measure the components.

Since I learned this kind of stuff only in the school
of hard-knox, I refer to it as the "empirical" method. ;-)

Cheers!
Rich

Paul Burridge wrote:

I'm simply trying to establish the radiation resistance of a non-ideal
antenna so I can reasonably match it to the output impedance of the
transmitter PA stage. The figure is likely to be very low, given that
this antenna is highly non-ideal. I'm not interested in plotting polar
patterns of the radiation distribution!
--

"I expect history will be kind to me, since I intend to write it."
- Winston Churchill


Paul Burridge December 14th 03 12:53 PM

On Sun, 14 Dec 2003 02:10:56 GMT, Rich Grise
wrote:

I remember as WN0GJS tuning the pi-net output to a piece of
300-ohm twin-lead thru a PL-259!

So make a little amp. with a pi output, tune it up, and
measure the components.


Can you exand a bit on this please, Rich? Sounds like it might be a
useful technique.

Since I learned this kind of stuff only in the school
of hard-knox, I refer to it as the "empirical" method. ;-)


The best school all right, but the fees are high. :-(
--

"I expect history will be kind to me, since I intend to write it."
- Winston Churchill

Paul Burridge December 14th 03 12:53 PM

On Sun, 14 Dec 2003 02:10:56 GMT, Rich Grise
wrote:

I remember as WN0GJS tuning the pi-net output to a piece of
300-ohm twin-lead thru a PL-259!

So make a little amp. with a pi output, tune it up, and
measure the components.


Can you exand a bit on this please, Rich? Sounds like it might be a
useful technique.

Since I learned this kind of stuff only in the school
of hard-knox, I refer to it as the "empirical" method. ;-)


The best school all right, but the fees are high. :-(
--

"I expect history will be kind to me, since I intend to write it."
- Winston Churchill


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