[Amps] Ferrite Core for 160M PI Output ?
Jim Thomson
jim.thom at telus.net
Sun Jun 11 00:20:39 EDT 2017
Date: Sat, 10 Jun 2017 14:09:05 -0700
From: Paul Baldock <paul at paulbaldock.com>
To: "Amps group" <amps at contesting.com>
Subject: [Amps] Ferrite Core for 160M PI Output ?
Message-ID: <593c5ff4.4bd1620a.e42b5.0bd9 at mx.google.com>
Content-Type: text/plain; charset="us-ascii"; format=flowed
<When I said Ferrite I should really have said Toroidal so as to
include Iron Powder.
- Paul
What's the best PI Output Ferrite Core(s) to use for a 1.5KW tube amp?
Thanks
- Paul
KW7Y
## Powdered Iron. #2 MIX. These are the RED ones.
T225-2B. Beware, the T225-2A is only .5 inch thick ...
IE laying on the table with hole pointed at the ceiling, its
.5 inch tall.
## The T225-2B is a full 1 inch thick. You require at least 2 of them
for 1.5 kw out for cw and ssb. For RTTY, you require 3 of them.
## these have been in use since the 70s..for 160 + 80m.
## I think marv calculated the heat at aprx 57 watts of diss, regardless
of how many core are used. They run hot..normal.
## If 3 used, the entire mess ends up being 2.25 inch OD x 3 inches long.
Bigger OD and length, once the wire is wound onto them.
I found some air dux..which used 12 or 14 gauge wire.... and had the turns
spaced closer than normal air dux. Worked perfect for the 160M conversion
project I was working on. Zero heat vs the stack of torroids. The air dux
weighed nothing vs the hefty weight of the 3 stack I also tried. The airdux
ended up being aprx the same diam and length as the torroid stack.
## space wide, the torroid stack save me nothing. 160m is pretty forgiving,
with long leads, coil close to cabinet side walls etc.
Jim VE7RF
More information about the Amps
mailing list