There is a big difference between a multiband toroid up thru 10M and another
for just 80/160 as we have been discussing.
From a packaging constraint a properly sized toroid is an acceptable
compromise to many.
Carl
KM1H
----- Original Message -----
From: "Gary Schafer" <garyschafer@comcast.net>
To: "'Larry Benko'" <xxw0qe@comcast.net>
Cc: <amps@contesting.com>
Sent: Sunday, December 23, 2012 1:22 PM
Subject: Re: [Amps] hf-2500
Hi Larry,
My problem was that of low efficiency and getting rid of the shorted turns
made quiet a difference. If I remember right the power out went up around
300 watts on 20 meters.
We had a discussion about this on AMPS a year or so ago. It should be in
the
archives.
73
Gary K4FMX
-----Original Message-----
From: Larry Benko [mailto:xxw0qe@comcast.net]
Sent: Sunday, December 23, 2012 1:08 PM
To: garyschafer@comcast.net
Cc: amps@contesting.com
Subject: Re: [Amps] hf-2500
Gary,
Nothing is black and white! Just because someone says something there
is always more to the story. Air (u=1) definitely has considerable flux
leakage. Obviously as the permeability goes up so does the coupling.
It is clear to me that the line between lots of flux leakage (u=1) and
virtually none (u=100s) there is a gradual increase in coupling. For
u=6 or u=10 shorted turns are not a clear NO but a qualified
no/yes/maybe. I saw a slight increase in heating with shorted turns but
not a catastrophic increase. A good designer would take this into
consideration.
73,
Larry, W0QE
On 12/23/2012 9:22 AM, Gary Schafer wrote:
> W8JI says that shorting turns on a toroid is not a good thing to do.
He said
> that shorted turns on an air coil cause much less of a problem because
there
> is considerable flux leakage on the air coil.
>
> 73
> Gary K4FMX
>
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
-----
No virus found in this message.
Checked by AVG - www.avg.com
Version: 10.0.1430 / Virus Database: 2637/5483 - Release Date: 12/24/12
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|