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R. Scott[_3_] · January 29th 14, 05:15 PM posted to rec.radio.amateur.antenna

On 1/28/2014 1:25 AM, wrote:
On Monday, January 27, 2014 8:01:29 PM UTC-6, wrote:

With a 3/8x24 thread mount, I would just use a 1/4 wave.. So much

easier and better looking. Most loading/matching coil schemes are going

to look fairly ugly in a case like that as you usually can't enclose

them in anything.

Pondering.. About the only other easy way to make a 5/8 whip
that would screw into that mount would be to take a glass whip
and then rebuild it into a 5/8 for 2m. You would need to strip
the original wire, or at least partly, then wind a loading coil
at the base, and then pretty much straight up to make the
5/8 element.
That would work.. The reason I call the coil for the 5/8 a
loading coil, rather than matching coil, is the coil is
tuning the 5/8 whip to be a 3/4 wave electrically, which is
resonant. Some ground the coil, and tap at the best match.
But I prefer an ungrounded coil. Why? If it's ungrounded, it
can also be used on other bands. IE: a 1/4 wave whip on a lower
freq.. I used to use my 10m 5/8 ground planes on 30m as 1/4 waves.
But you can't do that with a grounded coil. Works fine ungrounded.

I will give that a try. Thanks for the discussion gents, let me clear
some things up that I should have posted from the start.

The Iron Horse Whips are loaded HF Whips, I have them for all the bands,
but I dont have a 706 anymore as I changed to a 746pro and that doesnt
do Mobile well. Plus I have several CB antenna whips as people give
them to me thinking I could use them HI. So I could easily go buy a
3/8x24 2 meter antenna I would rather experiment with the whips on a 5/8
loaded base.

Im in the Seattle area so most of the 2 meter repeaters are high up ...
not an issue with hitting them. I have not used my FT-1500 in a while
and thought I would see if anyone is on any more.

The vehicle is a 2011 F-350 and I have the Fender Mount CB. Like I said
I use it only for the RV runs. Thus I would like to experiment with one
of the whips to run a 2 meter. I could have easily did a 1/4 wave
vertical but thought that 5/8 would be better experiment.

the loaded 5/8 ungrounded as NM5K posted just might be what I need. I
was looking for how many turns of wire might do the trick. Problem is I
dont have a GDO to get the right turns so thats why I was hoping to
find someone whom ad done it before

.

Anyway ... Ill start with 3/4 wave of wire and wrap the 1/2 wave section
in a coil and have the last 1/4 go vertical up the fiberglass ...

Ill let you know how it comes out.

Scotty W7PSK.