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Technical Topics => Equipment => Topic started by: ChrisSmolinski on May 05, 2021, 1326 UTC

Title: Looking for suggestions for a circa 4100 kHz directional antenna
Post by: ChrisSmolinski on May 05, 2021, 1326 UTC
I'd like to build an antenna for the 4100 kHz unlicensed beacon band, with directivity towards the desert SW where most of these beacons are thought to live. While I've got a fair bit of room for large antennas, I don't really have the adequate space to install a long Beverage (my first choice) aimed that direction (about 270-280 degrees based on great circle maps), without running a *lot* of coax into the woods to locate the feedpoint there.

So looking for suggestions for some potential antenna designs. One thought is a KAZ/D-KAZ (or another MWDX antenna) scaled down for that band. Any input on the feasibility of that, or other antennas I should be considering?
Title: Re: Looking for suggestions for a circa 4100 kHz directional antenna
Post by: RobRich on May 05, 2021, 1739 UTC
I would say flag or pennant, but since it can be stationary with fixed directivity for your purpose, perhaps even just an EWE antenna. Tweak the terminating resistor value to peak your desired band.
Title: Re: Looking for suggestions for a circa 4100 kHz directional antenna
Post by: redhat on May 05, 2021, 1856 UTC
Some folks have had good luck with the D-Kaz on lower frequencies, especially medium wave.  Perhaps this could be scaled down slightly for 4 MHz?
http://durenberger.com/wp-content/uploads/2019/11/D-KAZ-COOKBOOK-Pt1.pdf (http://durenberger.com/wp-content/uploads/2019/11/D-KAZ-COOKBOOK-Pt1.pdf)

+-RH
Title: Re: Looking for suggestions for a circa 4100 kHz directional antenna
Post by: M R I on May 05, 2021, 2350 UTC
After you implement your antenna choice. Let us know your results.
Title: Re: Looking for suggestions for a circa 4100 kHz directional antenna
Post by: Ray Lalleu on May 10, 2021, 1027 UTC
Look at the design of reversible Beverage antennas :
they use a double wire, and components to reverse the beam,
so you could get a feed point near your house.
Title: Re: Looking for suggestions for a circa 4100 kHz directional antenna
Post by: syfr on May 17, 2021, 0006 UTC
2 element inverted vee array?