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Lushy · March 28th 07, 12:22 AM posted to rec.radio.amateur.antenna

wrote:
On Mar 26, 5:24 pm, "Lushy" wrote:
I have a old 2 piece hollow 11 ft surf rod in the shed and need a
mobile antenna and a sand flag on my Jeep Wrangler. I thought I
would be able to do both with the fishing rod. Question 1. How much
minimum wire would I need to load it up on all Hf Freqs (I have a
tuner).
Question 2. Could I bottom load it with a coil?
It would be connected to the tuner with RG 58 coax (about 10 ft).
Lushy
VK3HDL

--
This life is not a rehearsal it is the real thing!

How would you mount, insulate a surf rod? Seems it would be
easier to just scrounge up an old glass whip antenna, and modify
it. It will fit the usual threads for antenna mounts.
I have a couple of those that I have built, and both work all
bands. But mine are center loaded, not base loaded.
I strip all the original winding from the glass whip, and then
wind a new larger coil bugcatcher style.
The one I usually use is a 6 ft glass whip, which was originally a
20 meter hamstick. The coil which is appx 3 inches diameter,
and wound on a light plastic tube is just below the tip at the
5+ foot level. I then clamp a 5 ft stinger whip to the top of the
glass whip. The antenna is 11 ft tall total, and exactly center
fed. I also can use a 3 ft hustler mast at the base and the
antenna is 14 ft, and the coil at 8 ft+. I only do that parked.
I change bands the same way you would a bugcatcher by
tapping the coil, and I can also go higher in freq by using a
shorter stinger.
My original all band antenna was basically the same, but it's
total length is 10 ft, and was built on a 5 ft firestick CB antenna.
It's coil is 2.5 feet above the base. I still use it if I want the
coil
lower for tree purposes, etc..
Using a tuner to load a mobile whip is about the last way you
want to go. On most lower bands, max current will be at the
tuner coil. No bueno.. A base load would be better, but a
center load gives much better current distribution and efficiency.
Thats why my newer antenna has the coil higher, and also
is why I often add the lower mast when parked. That extra
3 ft below the coil really gives the efficiency a good boost
when on the lower bands. My coil is at the level some other
antennas tips would be.. In most cases, my antenna will
thrash those.. I've done it a few times on "park and compare"
tests.. I once compared against a usual hustler setup on 75m.
I almost felt sorry for the owner, who is a friend of mine. :/
That hustler was a dummy load on a stick...
MK

Thanks mk, I was going to turn a base for the rod and mount the coax
connector on the outside of the area where the reel is fastened as it is
hollow and then fix the base two small muffler clamps to the bullbar.
As you state centre loading is the go and can be done with this rod as it is
a two hollow glass rod.
Lushy