The AM Forum

...HI FROM TIM...I KNOW THEY ARE A COMPROMISE, BUT WHAT ARE YOUR THOUGHTS ON THE BETTER HF MOBILE WHIPS?...I'M THINKING 80/75, AND 40. I HAVE THE TYPICAL PRO-AMS, AND THEY WERK OK, BUT WHAT DO YOU THINK IS BETTER?....sk...

Numerous shoot-outs have shown the "bugcatcher" variety are generally the best, although the continuously tuned screwdriver types (e.g. High Sierra) are close and are much more user/QSY friendly.

Unfortunately, there aren't many mobile HF antennas that don't look absolutely ridiculous. When I was thinking about HF mobile, there was one company out there that makes a hinged frame with a linear actuator that lays the antenna down into the bed of a truck when not in use.

I prefer not to ride around sporting the 'Illudium PEW-36 explosive space modulator' on top of the truck.

Check out the marine variety of HF whip antennas...They are long and ugly and require a tuner, but at least they cost a lot

I was very happy with my KJ7U http://www.kj7u.com/  (http://www.kj7u.com/) screwdriver. Used it all bands 160-6 with good results

Hamsticks are going to be less efficient, especially on 80/75, but they have proven very functional for me, and they have a low "nerd factor", with their small diameter, low wind load, and lack of guy wire requirements. 

I am extremely satisfied with their performance on 40 meters and up - routinely work all over the world on 40 CW with them.  Consistently get  "great signal for a mobile" comments.  Work even better at higher frequencies. Somewhat wimpy on 75/80 but routinely make solid contacts there as well.

73, Chris, AJ1G Stonington, CT

 

What a dillemma - unless you are a bachelor farmer, it does look silly to have these things strapped on. I was operating AM mobile this weekend on a trip through Vermont. I had my Command Set A-Go-Go in the car and this "thing" on the back. I pulled into a rest stop way in the back to do some reconfiguring (AM on 3885 to CW on 3570) and a small Canadian family walked all the way across the parking lot to point and ask questions about the antenna - I am not kidding - just last night.

Mike

Chris, You have an awesome mobile signal with the Hamstick setup.

One more plug -

Another rather simple and not so fragile mobile setup is to use a 102" stainless CB whip and ball mount with a base load or a tuner. I did this in college on 40/75M because I did not want my Hustler broken in half AGAIN. Sometimes students get bored. The CB whip is less interesting.

Jamie, KF2VM runs a 102 inch whip on a spring mount on top of a large base loading coil (6 inch Dia), on the roof of his Jeep. It is extremely effective (but narrow) on 75M.

Mike WU2D

I've used the hamstick design, and they work FAR better than the Hustlers I've used.

The advantage to the hamstick is that the coil is wound as close to the top of the base section as they can get it, making it essentially center-loaded. Unfortunately, they use the same diameter base for the 75 meter ant as they do for all the other bands. Even using the thinnest wire they can, the bottom end of the coil comes within a few inches of the feedpoint, which kind of defeats the purpose of the design.

I've seen 160 meter hamsticks which use a much thicker base section. If they used that base for the 75 meter version, the design would gain as much on 75 as it does on the other bands.

That being said, the hamstick performs quite well on 75, and way outperforms the Hustler.

I would actually recommend the hamstick knockoff made by Ironhorse. They're electrically identical, but the original hamstick has its whip set in a fixed collet by setscrews. If you want to change radiators, you'll need to measure the whip length and tighten the setscrews. The collet on the Ironhorse version threads into the base, so you don't need to worry about setting the whip length every time you change bands. If you keep the sections paired, you need only screw the whip onto the base, the base onto the mount, and off you go.

My $0.02.

--Thom
Killer Agony One Zipper Got Caught

I know that if I were to go to the Philippines for any length of time, I would take my High Sierra and raise it up on one of those tripods and some ground radials and prolly a leanyear and do some DXexpedition on SSB and CW. I doubt if AM is real big in the RP. Hong Kong and Japan are the closest countries (Guam?) and I would have to catch the next Sun spot cycle to get into the magical part of HF operations from a half a World away. I guess there's an "FCC" there too and would have to get permission to set up anything.
I guess I gave myself a neat idea to try WorldWide commo...just wait for the next cycle and go then......I wonder if the wife can wait a few more years?????hmmmmm
Fred