I have a lot of hardline coax that I use for many things. I have some in
present use as a large value inductance because of its flexibility in
winding. I have now read that a wound inductance should have a smooth
surface ! Why is this? Does the corrugations of the outer surface introduce
facters that overide
the mechanical advantages of flexibility?
Regards
Art

"aunwin" wrote in message
news:et%zc.115105$Ly.34531@attbi_s01...
I have a lot of hardline coax that I use for many things. I have some in
present use as a large value inductance because of its flexibility in
winding. I have now read that a wound inductance should have a smooth
surface ! Why is this? Does the corrugations of the outer surface
introduce
facters that overide
the mechanical advantages of flexibility?
Regards
Art



The corrugations may add length and inductance that is difficult to
account.. Otherwise it is something I have never given much thought to as I
have always used smooth materials to wind coils. I have noticed that when
using a threaded rod for a radiator on 2 M the antenna worked out to be a
little shorter than expected.

On Thu, 17 Jun 2004 15:53:37 GMT, "Jimmie" Gfender@carolina
dot.rr.dot com wrote:

I have noticed that when
using a threaded rod for a radiator on 2 M the antenna worked out to be a
little shorter than expected.



This is very interesting! I had wondered about that myself! If
static is dissipated more efficiently on a sharp point, would an
antenna with a vertical with a needle point on the end tend to radiate
more energy in the vertical direction?

I have no clue about antenna performance in this situation. Just a
curious question really!

KI4DVI

Yes, I was wondering if would affect the inductance per unit length or maybe
adding distributed loading for the new historic design that is in the works.
I think it would take somebody well versed in 'Fields and Waves' to obtain
an authoritive answer on whether the field generation vectors would cancel
in the valleys
or bend and add to the generated field. I suppose the same question could be
applied to the use of a spring design that was then wound in a inductive
form possibly to obtain constant current flow over the physycal length as
opposed to the actual electrical length hich may well be more than 4 times
as long!
Regards
Art

"Jimmie" Gfender@carolina dot.rr.dot com wrote in message
. com...

"aunwin" wrote in message
news:et%zc.115105$Ly.34531@attbi_s01...
I have a lot of hardline coax that I use for many things. I have some
in
present use as a large value inductance because of its flexibility in
winding. I have now read that a wound inductance should have a smooth
surface ! Why is this? Does the corrugations of the outer surface
introduce
facters that overide
the mechanical advantages of flexibility?
Regards
Art



The corrugations may add length and inductance that is difficult to
account.. Otherwise it is something I have never given much thought to as
I
have always used smooth materials to wind coils. I have noticed that when
using a threaded rod for a radiator on 2 M the antenna worked out to be a
little shorter than expected.

"aunwin" wrote in message
news:mAlAc.58535$eu.29601@attbi_s02...
Yes, I was wondering if would affect the inductance per unit length or
maybe
adding distributed loading for the new historic design that is in the
works.
I think it would take somebody well versed in 'Fields and Waves' to obtain
an authoritive answer on whether the field generation vectors would cancel
in the valleys
or bend and add to the generated field. I suppose the same question could
be
applied to the use of a spring design that was then wound in a inductive
form possibly to obtain constant current flow over the physycal length as
opposed to the actual electrical length hich may well be more than 4 times
as long!
Regards
Art

"Jimmie" Gfender@carolina dot.rr.dot com wrote in message
. com...

"aunwin" wrote in message
news:et%zc.115105$Ly.34531@attbi_s01...
I have a lot of hardline coax that I use for many things. I have some
in
present use as a large value inductance because of its flexibility in
winding. I have now read that a wound inductance should have a smooth
surface ! Why is this? Does the corrugations of the outer surface
introduce
facters that overide
the mechanical advantages of flexibility?
Regards
Art



The corrugations may add length and inductance that is difficult to
account.. Otherwise it is something I have never given much thought to
as
I
have always used smooth materials to wind coils. I have noticed that
when
using a threaded rod for a radiator on 2 M the antenna worked out to be
a
little shorter than expected.




Also tried using threaded rod near 30Mhz, Their seemed to be no effect at
all on this trial. Chalk it up to skin effect 2m and near lack of it on 10M.