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eHam Forums => Antennas and Towers and more => Topic started by: KI4SJU on June 20, 2012, 07:48:06 PM



Title: Hustler 5BTV with Hamsticks
Post by: KI4SJU on June 20, 2012, 07:48:06 PM
I really dont have a way to lay down radials for my hustler 5BTV antenna that is mounted about 10 feet above the ground. I saw a article here on Eham and wanted to know if this will work ok for my antenna.

I want to buy two 20 meter and 2 40 meter ham sticks and mount them in a x patern on the mast of the 5BTV to act as radials. Or maybe get other ham sticks for different bands instead of two for one band. Since they are cut for the bands, I thought this might work better than no radials at all. Please give me your feed back!

Thanks so much!
73's

Here is the link to the article that gave me this idea.
http://www.eham.net/articles/17580


Title: RE: Hustler 5BTV with Hamsticks
Post by: KG4RUL on June 20, 2012, 08:24:26 PM
Scorpion Antennas sells a counterpoise adaptor for its's screwdriver antennas which uses hamsticks http://scorpionantennas.com/index.php?route=product/category&path=20 (http://scorpionantennas.com/index.php?route=product/category&path=20)  so the idea has merit.  BTW Hamsticks are no longer being manufactured - a suitable replacement called a HamTenna is made by MFJ


Title: RE: Hustler 5BTV with Hamsticks
Post by: KH6AQ on June 21, 2012, 12:54:59 AM
One Hamstick per band will be fine. Tuning two so they both have the same RF current would be a challenge.


Title: RE: Hustler 5BTV with Hamsticks
Post by: AC4RD on June 21, 2012, 04:20:05 AM
I'm sure you know this, but "Justen Case" ...  you do know you could use elevated, rather than ground-mounted radials, right?

I knew you knew it.  Thought it was worth mentioning anyway.  I've got a homebrew vertical for 20/15/12, feedpoint about 10 feet above ground, with a dozen elevated radials--works great.




Title: RE: Hustler 5BTV with Hamsticks
Post by: WB6BYU on June 21, 2012, 09:08:28 AM
That approach would work in theory.  In practice there are a couple additional aspects to
consider.

First, let's assume two horizontal radials at the base of the antenna.  The conventional
analysis assumes that the radials share the currents equally, in which case the radiation
from one basically cancels out that from the other, and there is no net radiation from
the radial wires.  However, with a sharply tuned antenna such as a Hamstick, it is very
difficult to get the input impedance equal on both without actually measuring it:  a small
difference in the amount of metal near the tips can shift the tuning quite a bit.  By
contract, radials made using a quarter wave of wire are easier to get matched - still not
perfect, but not as sensitive to detuning.  Is radiation from the radials a problem?
Perhaps not.

However, the narrow bandwidth of the tuned radials will decrease the operating
bandwidth of the overall antenna.

The other factor is efficiency:  while the 20m Hamsticks are about half-sized and the
losses aren't too bad, on 40m (and particularly on 80m) the efficiency is quite low. 
Your total antenna consists of the 5BTV in series with the radial system:  losses in the
radials will add to the rest of the losses.  Again, you're better off using elevated wire
radials if you can.

Les Moxon G6XN recommended using two (or more) shortened radial wires with a
SINGLE loading coil connected between all of them and the base of the antenna,
basically a loading coil with capacity hat that is tuned to resonance.  Because there
is only adjustment (the coil) for resonance rather than one for each radial, this
reduces the tuning issues.  I haven't tried it, but it seems like a reasonable approach.


Title: RE: Hustler 5BTV with Hamsticks
Post by: KI4SJU on June 21, 2012, 04:51:09 PM
Thanks for all the great feed back, in reality I cant really put down any radials,
elevated or ground due to my layout of property. So will adding these hamsticks or hamtenna make my 5btv work better? I was reading on a site somewhere that I should use two of the same band hamsticks, or will one of each work better? My last question is, how will I attach these antennas to the radial terminals under the 5btv? Should I use coax with a pl 259 on hamtenna side and then cut the coax in half and attach the center conductor and shield to the radial terminals? Sorry for the dumb questions, I am still new to the HF thing.

Thanks


Title: RE: Hustler 5BTV with Hamsticks
Post by: KH6AQ on June 21, 2012, 08:37:59 PM
You could save the trouble of Hamsticks and mount the 5BTV on the ground. If the ground is decent it can work ok with just a ground rod. If you can lay out some radials up to 20' long that's even better.


Title: RE: Hustler 5BTV with Hamsticks
Post by: KI4SJU on June 22, 2012, 03:54:18 AM
Ok I am really considering moutning the 5BTV on the ground. I have a few issues tho. It will have to be mounted close to the house, on a corner of my house. Wonder how bad that is going to effect the operation of my antenna, plus with it being lower to the ground will it operate better then being up in the air? I worry about RF hitting my kids with the antenna being on the ground, because the only location I can put it is on the corner of their room. Then I will not be able to put radials 360 degrees around my antenna, so how bad will that work? If you all think it will be better on the ground and should not bother my kids real bad then I will try it. I do have a ground rod hammered into the ground.

Here is a pic of my lay out I am working with... What do you all think?
http://i125.photobucket.com/albums/p79/btlacer/Proposal-1.jpg


Title: RE: Hustler 5BTV with Hamsticks
Post by: KQ6Q on June 22, 2012, 10:31:50 AM
Since you can't put up effective radials, and a trap vertical doesn't do well without them, have you considered one of the vertical dipole setups for Gap and MFJ ?  They're designed to work without radials.


Title: RE: Hustler 5BTV with Hamsticks
Post by: K5LXP on June 22, 2012, 11:25:01 AM
Depending on the band, using resonant radials may only be shifting where your energy is being dissipated.

You could save the trouble of Hamsticks and mount the 5BTV on the ground. If the ground is decent it can work ok with just a ground rod. If you can lay out some radials up to 20' long that's even better.

The 5BTV will "work" without radials as WX7G suggests.  It's not optimum but since we're dealing with a compromise setup, it seems a simple compromise is better than a costly and complicated compromise.


Mark K5LXP
Albuquerque, NM