Hi Trevor,
Luis IV3PRK has good info on DHDL, based on the original by George Wallner,
AA7JV
See http://www.iv3prk.it/TX3A-DHDL.htm
I use a 1200 ohm terminating resistor; source resistance is about 900 ohms.
900/75 = 12 so turns ratio to match is 3.5:1 I use a 2 turn primary and 7
turn secondary on a BN73-202 core.
Make sure that you have a feedline choke near the feed to the DHDL so you don’t
get common mode noise.
They work well!
> On 28 Nov 2017, at 15:07, MR TREVOR DUNNE <ei2glb@eircom.net> wrote:
>
> Hi All
>
> My quest to better my station continues I want to try a DHDL can someone
> recommend a matching Transformer and what size termination resistor should I
> use,
>
> I have some bn73-202 cores and I wish to use 75ohm feed line,
> _________________
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