Bruene coupler

[p.larner]

I am trying to build a dual bruene coupler for a project, All the ones i see use 2 torroid coils with about 12 turns on each with the main wire coax thru the coil center with one side of the coax screen grounded,thats all good,But nowhere do i see any info as to the winding direction of the toroids,are they A: both wound clockwise, B: one clockwise and one counter clockwise or C:it doesent matter as long as they are both the same?,sorry for this basic question but ive looked at lots of articles but see nothing about the winding direction mentioned,P.S i hope its ok to ask in this section,thanks in advance.

[p.larner]

i saw that vid but he doesent mention the winding details tho as far as i can see,hence my question.

[Andy Chee]

Normally the winding direction doesn't matter because there is only a single coil.

But if you are winding two coils on a single toroid, both windings should be in the same direction (doesn't matter which direction).

[trackersoft]

Just as an aside, I am past President of the Collins Collectors Association and I had a chance to visit Warren Bruene at his nursing home before he passed. He was a very interesting guy! The only art work in his rooms was a giant Smith Chart hanging on the wall. I run our collinsradio.org website and we have scanned many of his log books that he hand wrote while at Collins and will be posting some of those up on the web site at some time. I spent an evening going through some of his notes that he wrote during WWII where he was designing the next generation of Collins products (30K1 and KW1) that would be released after the war. Very interesting reading!! It will take a few months for us to get this material up on the web site as it is an enormous volume of material. PM me if you want a heads up when we get this released.

[p.larner]

andy this is a dual directional coupler so uses 2 coils,as in the vid,i find it hard to belive i cant get a strait answer to this very basic question,cheers+73.

[Terry Bites]

The torroid indctuance is calculated from the lowest frequency of interest.
It is a broadband transformer.

In the pdf its states that 2pi()fL>>R. Calculate the L required, from that and the Al of the torroid you can work out how many turns are needed.

[p.larner]

Please read my question,i dont need the inductance but the winding direction of both coils ok,why is it so hard to get an answer for what i asked?.