HFU HF Underground

Technical Topics => Equipment => Topic started by: Josh on June 13, 2017, 1719 UTC

Title: Low Band Antennae
Post by: Josh on June 13, 2017, 1719 UTC
What do you guys use for low band? Say 25 to 88MHz? Also apparently the eskip is rolling from the midwest to Montana to south of Mehico right now.
Title: Re: Low Band Antennae
Post by: BoomboxDX on June 14, 2017, 0505 UTC
A long time ago (before the antenna blew down) I had an 11 meter quad loop that worked real well on VHF low band. I heard guys talking in Louisanan, Cajun like accents talking about oil rigs, and other interesting transmissions between 30-33 MHz or so. And I'm in the PNW.

That, of course, was in 1990 or so and the sunspots were up.
Title: Re: Low Band Antennae
Post by: ThaDood on June 14, 2017, 1052 UTC
      Heck, just use a 102" CB whip antenna. No baseload coils to attenuate higher FREQ's. Or, ya might be able to grab a Low Band VHF commercial 60", or so, whip for nothing. Many commercial dispatchers are leaving the VHF Low Band for UHF, or cell phones, so ya might just pick-up a freebie there. 
Title: Re: Low Band Antennae
Post by: Josh on June 14, 2017, 1536 UTC
See that's kinda what I was thinking, use a cb whip and be done with it.
A beam as boombox mentions would be nice but more cost and work than I want, just have to find a cheap 1/4w. A beam would open and close the band but I want something simple and omni, the opposite of a beam. Used to have a Francis Antenna model Wheeler Dealer, a fibreglass 1/4w stick that had 3 quarter waves fed in phase bundled inside the fibreglass, same diameter as a standard cb whip, had grossly increased lower angle of radiation over a 1/4w stick in the same mounting point. We mounted the a standard stainless whip and set the fs meter to full scale a few wavelengths away, then mounted the wheeler, the wheeler resulted in a few times more low angle rf power at the same distance and rf power out, blew us away. Sadly they don't make it anymore.

http://www.cbtricks.com/ant_manuals/francis/cb_28/ad/index.htm
Title: Re: Low Band Antennae
Post by: BoomboxDX on June 17, 2017, 0647 UTC
FWIW, my 11 m quad antenna, which I mentioned, was a single quad loop. No second element. Fairly easy to build. It was on a wooden cross frame I nailed together, and I could turn it and aim the lobes NS or EW. But it had pretty good reception in most directions.
Title: Re: Low Band Antennae
Post by: Looking-Glass on June 17, 2017, 0743 UTC
Radio Shack/Archer three radial 5/8 Groundplane CB antenna shortened by three feet done the trick for me! ;D
Title: Re: Low Band Antennae
Post by: ByteBORG on June 17, 2017, 1331 UTC
</me holds a skull>
Alas poor Radio Shack,
we knew Ye well...
Title: Re: Low Band Antennae
Post by: Josh on June 17, 2017, 1421 UTC
Ah Shakespeare, that rascal.

"My wit's diseased!"
Hamlet



The single loop sounds nice, and I know how well they work. Just before my HAM ticket came in the mail I'd thumbtack'd a wire loop for 6m on the bedroom wall, fed at a bottom corner with coax. The day the license came was a vhf contest and propagation was coast to coast. 3 watts from one of these; http://www.eham.net/reviews/detail/930

On the lines of cb antennae, think I'll just get a decent mobile cb ant and mount it in place of the stinger on the disconey. Thanks for the input.

Title: Re: Low Band Antennae
Post by: Duffer on July 04, 2017, 0720 UTC
I'm a UK ham, so can transmit on 70MHz

I use this-
http://www.mirfield-electronics.co.uk/products/me64270-quad-band-6m-4m-2m-70cm-colinear/

It's crap but gets me on the band.

When I hear 'OIRT FM' stations from East Europe I know the band is open...
https://en.wikipedia.org/wiki/International_Radio_and_Television_Organisation

Duffer
Title: Re: Low Band Antennae
Post by: Josh on July 04, 2017, 1620 UTC
Hey thanks for bringing that up on the HAM multiband verticals. You reminded me I've a few fibreglass comet multiband HAM base antennas in the garage, will have to see if any covers 6m, then I'm good to go.