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Re: [TowerTalk] Phasing transformer answers

To: "'Glen'" <>
Subject: Re: [TowerTalk] Phasing transformer answers
From: "Clint Talmadge W5CPT" <>
Date: Mon, 22 Aug 2011 14:34:50 -0500
List-post: <">>
I considered the insulation, but for 30M the most I can run is 200W, so I
don't think it is going to be a factor.  I am going to get a roll of 14GA
Romex (which is solid wire)  and use the insulated wires stripped out of the
outer jacket.  I will play with both a flat wind and a twisted wind and see
which I can get the neatest.  I will take pictures and post them so I can
show others what it takes. 

Clint Talmadge - W5CPT

-----Original Message-----
From: Glen [] 
Sent: Monday, August 22, 2011 11:07 AM
To: Clint Talmadge W5CPT
Subject: RE: [TowerTalk] Phasing transformer answers

It does not matter if you use solid or stranded.  What matters is the
current and voltage depending on the power you are putting into the
transformer.  W2FMI Jerry Sevick recommends sleeving #14 wire with Teflon
tubing before winding the transformer.  That is how I make mine now.


Glen K4KV

-----Original Message-----
[]On Behalf Of Clint Talmadge W5CPT
Sent: Monday, August 22, 2011 9:33 AM
Subject: [TowerTalk] Phasing transformer answers

Bill - KR8L - came up with the answers, as well as the original calculations
for the windings.

Bill said:

"Well ... I can't imagine that solid or stranded would make a difference in
this application, but that's just a guess.  Thinking back to the many
toroidal inductors and transformers that I have done for kits, it seems like
they are usually made with solid, enameled wire.  So, I would say that solid
is a safe way to go for sure, but I would bet that stranded would work also.

Looking through the reference * that I sent earlier, I found these words on
page 3-4: "The windings on transmission-line transformers consist of
parallel wires or twisted wires....  Some controversy exists about whether
the parallel-wire winding is better or worse than the twisted-wire winding
in terms of impedance and efficiency, but both methods seem to provide
satisfactory results.  Typically, the twisted-wire windings are configured
to have between 8 and 10 turns per linear inch.""

* - A chapter on transformers from an old out of print book -

Clint Talmadge - W5CPT

-----Original Message-----
[] On Behalf Of Clint Talmadge W5CPT
Sent: Sunday, August 21, 2011 8:22 AM
Subject: [TowerTalk] Phasing transformer questions.

I am phasing two verticals together for 30M and using the Trifilar wound
toroidal transformer found in Joe Carr's "Practical Antenna Handbook" to do
so.  A friend, (more knowledgeable than I,) calculated 19 turns on a T300-2
core.  I recently found the core and now other questions have arisen.

Does the winding have to be solid wire, or can I use stranded wire, or does
it matter?  And should the windings be flat wound, such as ribbon cable, or
twisted together? I have seen both methods.

Any other information which I really need to know would also be appreciated.

Clint - W5CPT


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