Invertef F antenna for HF - HomeBrew Forum at eHam.net

$\'\'$

$\'\'$

$\'\'$

eHam.net Forum : HomeBrew : Invertef F antenna for HF

Forum Help

1-3 of 3 messages

Page 1 of 1

Invertef F antenna for HF	Reply
by G7AQK on May 5, 2008	Mail this to a friend!
I would like to build a 40m inverted F antenna but have not been able to find anything on the web regarding recommended materials or dimensions. I have found some Information on the DDRR antenna and am considering using these dimensions as a starting point. Can anyone provide any more information or direct me to a suitable source for inverted F antenna design information? Neil G7AQK

RE: Inverted F antenna for HF	Reply
by G7AQK on May 5, 2008	Mail this to a friend!
Sorry, slip of the typing finger. Title should read Inverted F antenna for HF. Neil G7AQK

RE: Invertef F antenna for HF	Reply
by WB6BYU on May 5, 2008	Mail this to a friend!
I've got some studies of the inverted F antenna around somewhere, but it basically is a DDRR that hasn't been bent into a circle. It is a short vertical radiator (the grounded vertical part) with heavy top loading (the horizontal element, which will be close to 1/4 wave long). The feedpoint tap will depend on antenna height, losses, etc. The taller you can make the antenna the better. If you look at Robert Dome's analysis of the QST DDRR design you may be able to extract the appropriate formulas from his math. Otherwise start with about a quarter wavelength total vertical + horizontal and adjust the tap for minimum SWR. Or somewhat shorter than a quarter wave if you are using a tuning capacitor of some type on the end.

Page 1 of 1

Next Topic: Where to find a rotary switch
Previous Topic: relays for HF?

Email Subscription
You are not subscribed to this topic.

Check our help page for help using Forum, or send questions, comments, or suggestions to the Forum Manager.

$\'\'$