Thanks for the suggestion, Rick. The T-10 is not a 200 ohm feed design -
but nominally 50 ohm. From my approximate measurements, Z actually varies
between 25 and 125 ohms. From my Nec/Wires model, feed Z varies similarly.
You are correct that the KLM and other LPDAs are designed for 200 ohms.
73, Dave W2TA
> From: Rick Mainhart <firstname.lastname@example.org>
> To: email@example.com
> Subject: Re: [TowerTalk] Tennadyne LPDA
> Date: Friday, April 10, 1998 11:41 AM
> My recollection of the KLM 10-30 LPA is the design impedance was not 50
> ohms, but 200 ohms with a 4:1 balun at the feedpoint. You may wish to
> measure the impedance, model it with one of the many good programs
> available, or look for LP.ZIP on the net. LP will allow you to enter all
> your critical measurements, and give you a quick design based on the
> formulas in the ARRL handbook (and other sources).
> Hope this helps.
> Rick, WB3EXR
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