Art, I should have added - you must take the opportunity to increase
conductor diameter. You have twice the length of coil with only 70% of the
number of turns to wind along it.

There is NO other way to increase Q of a coil while maintaining the same
inductance.

If you think about it it's fairly obvious.
---
Reg

"Reg Edwards" wrote
If both coil diameter and length are doubled, and number of turns are
reduced to 71% of the number you started with, then you will end-up with
the
same inductance as before but the loss resistance will be 71% smaller.

You can continue to do this until radiation resistance becomes the
predominant loss.

Download program SOLNOID2 for coil design and to study these effects.
--
=======================
Regards from Reg, G4FGQ
For Free Radio Design Software
go to http://www.g4fgq.com
=======================


"Art Unwin KB9MZ" wrote in message
...
Richard Clark wrote in message
. ..
On 12 Oct 2003 03:24:10 GMT, oSaddam (Yuri Blanarovich)
wrote:

Art Unwin, KB9MZ wrote:
"The markings are 3600 - 5000 KC."
It was used in a radio or transmitter operating in that range.
(German
WW II
SK10?)

Yuri

Hi Yuri,

More probable is Marine DF.

73's
Richard Clark, KB7QHC

After digging into this subject so that I fully understand it I found
that this particular antenna did not work as it should have done. This
'dummy' assumed that I could obtain any Q that I wanted, however
actual inductor was very inefficient for top band use ( very
broadbanded because of losses.)
I went from 4 inch diameter inductance windings to
a 12 inch o/a diameter with 0.6, O.D. copper tubing for a total length
for the inductor of 35 inches. My intention is to now flatten the
copper tubing so the edges to provide minimum interwinding
capacitance.
However I do want the maximum Q available so the antenna is narrow
banded and inductance change is made by lessening the inductance
length for moving around the band.( or possibly the insertion of a
brass rod)

What other options do I have for increasing Q other than silver
plating of the copper?
I opted away from LITZ wire as I figured that top band was too
high a frequency to benefit from its properties.
Any comments or discussion of the subject would be very apreciated
Best regards
Art