----- Original Message -----
From: "Jeff Blaine" <keepwalking188@yahoo.com>
To: "Manfred Mornhinweg" <manfred@ludens.cl>; <amps@contesting.com>
Sent: Monday, October 07, 2013 3:07 PM
Subject: Re: [Amps] 160M PI network Toroidal Coil
It probably does not matter in any event.
Either the gentlemen is running CW/SSB - and in that case, whatever coil
he uses will work out FB as the duty cycle won't be much of an issue - a
few watts lost one way or the other won't be of significance.
Or he will be running a data mode and without a lot of case, the
transformer be at the center of a self-correction event occurring long
before the coil (of whatever construction type) is a factor.
73/jeff/ac0c
www.ac0c.com
alpha-charlie-zero-charlie
-----Original Message-----
From: Manfred Mornhinweg
Sent: Monday, October 07, 2013 12:58 PM
To: amps@contesting.com
Subject: Re: [Amps] 160M PI network Toroidal Coil
Carl,
The T-225/225B (there is no T225-2A) size buys you absolutely nothing
over the 200 size except a few more turns of wire of the same
diameter.
Wrong. While the inductance per turns of the T-225 and the T-200 is the
same, the larger core will run at lower flux density when used in the
same amp, wound for the same inductance. So its volumetric loss will be
much lower. It has more volume though, so that the total loss decreases
only somewhat. But it has much more dissipation surface, so that it ends
up being able to handle significantly more power, or run cooler at a
given power level.
** Youre certainly wrong all right Manfred.
The slight size difference is not enough to make much difference especially
when only about 1/2 the turns the core is capable of for a pratical SB-220
conversion using stranded #14 are used and well spaced. When using a pair
of T200-2 or a single T200-2A the pair will run cooler.
And the 225B size is of course much larger and very different from the
non-B size.
** It is twice the height and the same diameter as the T-225. The T-200A has
the same double height.
And at least there _was_ a 225A. It shows up in older catalogs. The
T-225A-2, as listed in an Amidon catalog from 1995, was very similar to
the current B size, only that the inner diameter was a little bit smaller.
Manfred
** I really dont care about ancient history but FYI I was selling the 225A
back in 1985 and the B when it replaced it around 92-93.
Carl
KM1H
========================
Visit my hobby homepage!
http://ludens.cl
========================
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
_______________________________________________
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: 10.0.1432 / Virus Database: 3222/6229 - Release Date: 10/07/13
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|