"H. Adam Stevens, NQ5H" wrote in message ...
QST
It's been a while since I posted all that bazooka data that made me stick to
dipoles, so here goes:
I've been using Hustlers mobile for almost 40 years and find them adequate;
The mast I bought in 1970 only recently failed.
I'm reworking my HF mobile installation around a TS-480HX and decided to
graduate to a screwdriver. I bought a Tarheel 200.
I prefer to operate a mobile antenna at it's resonant frequency and match to
the impedance of the transmission line with a transformer.
So here I present the resonant feedpoint impedances of a Hustler (small
resonators), the Tarheel 200 screwdriver and a 103" whip on a bug catcher on
a 54" Hustler base. All antennas on the same ball mount. Measurements by
MFJ. "Resonant" implies X=0.

band Hustler Screwdriver 103"/BugCatcher/54"
80 21 ohms 9 ohms 23 ohms
40 25 11 na
20 30 30
10 40 32

I really thought the huge bug catcher would do better.

I'm not sure if I'm getting the problem. Is the bugcatcher failing to
perform?
I would *think* the bugcatcher would be the best of the bunch
regardless of the thickness of the lower mast. Which is the best on
the air? That bugcatcher *should* be kickin butt on 80m compared to
the others. "I'm assuming the screwdriver is shorter". At the least,
it should be equal to the screwdriver. Normally, I would think
better...


The screwdriver shows encouraging results for signal improvement over the
others on 80 and 40.

Even the bugcatcher? Thats weird...
Seems the diameter of that bottom conductor on the screwdriver makes a big
difference at the lower frequencies.

I don't really buy it though. Shouldn't make *that* much difference.
Something seems weird to me....Not sure what it is though...MK

Mark Keith wrote:

"H. Adam Stevens, NQ5H" wrote:
band Hustler Screwdriver 103"/BugCatcher/54"
80 21 ohms 9 ohms 23 ohms
I really thought the huge bug catcher would do better.

I'm not sure if I'm getting the problem. Is the bugcatcher failing to
perform?

With that much whip and base section, the bugcatcher coil probably
had shorted turns to raise the resonant frequency. It is well known
that shorted turns on a high-Q coil lowers the Q. (Try a shorted turn
on an iron core choke.)
--
73, Cecil http://www.qsl.net/w5dxp



-----= Posted via Newsfeeds.Com, Uncensored Usenet News =-----
http://www.newsfeeds.com - The #1 Newsgroup Service in the World!
-----== Over 100,000 Newsgroups - 19 Different Servers! =-----

"Cecil Moore" wrote in message
...
Mark Keith wrote:

"H. Adam Stevens, NQ5H" wrote:
band Hustler Screwdriver 103"/BugCatcher/54"
80 21 ohms 9 ohms 23 ohms
I really thought the huge bug catcher would do better.

I'm not sure if I'm getting the problem. Is the bugcatcher failing to
perform?

With that much whip and base section, the bugcatcher coil probably
had shorted turns to raise the resonant frequency. It is well known
that shorted turns on a high-Q coil lowers the Q. (Try a shorted turn
on an iron core choke.)
--
73, Cecil http://www.qsl.net/w5dxp


Nope, the whole coil, I just found the resonance and noted the value of R.
73
H.
NQ5H

Cecil Moore wrote in message ...
Mark Keith wrote:

"H. Adam Stevens, NQ5H" wrote:
band Hustler Screwdriver 103"/BugCatcher/54"
80 21 ohms 9 ohms 23 ohms
I really thought the huge bug catcher would do better.

I'm not sure if I'm getting the problem. Is the bugcatcher failing to
perform?

With that much whip and base section, the bugcatcher coil probably
had shorted turns to raise the resonant frequency. It is well known
that shorted turns on a high-Q coil lowers the Q. (Try a shorted turn
on an iron core choke.)

Shouldn't be that big a deal. I have some number of shorted turns on
mine all the time. Doesn't seem to hurt mine too much. Also my normal
"mast" is only wire . Not having a thick mast doesn't seem to hurt
much either in my case. Dunno...It still seems weird to me. That
bugcatcher should be the clear winner, unless the screwdriver is about
the same height, coil position, etc. MK

"Mark Keith" wrote in message
om...
Cecil Moore wrote in message
...
Mark Keith wrote:

"H. Adam Stevens, NQ5H" wrote:
band Hustler Screwdriver 103"/BugCatcher/54"
80 21 ohms 9 ohms 23 ohms
I really thought the huge bug catcher would do better.

I'm not sure if I'm getting the problem. Is the bugcatcher failing to
perform?

With that much whip and base section, the bugcatcher coil probably
had shorted turns to raise the resonant frequency. It is well known
that shorted turns on a high-Q coil lowers the Q. (Try a shorted turn
on an iron core choke.)

Shouldn't be that big a deal. I have some number of shorted turns on
mine all the time. Doesn't seem to hurt mine too much. Also my normal
"mast" is only wire . Not having a thick mast doesn't seem to hurt
much either in my case. Dunno...It still seems weird to me. That
bugcatcher should be the clear winner, unless the screwdriver is about
the same height, coil position, etc. MK

I thought so too.
Must be the dirty threads.
Not at all realistic anyway.
I used the same bugcatcher configuration with a roof mount on a Pontiac in
1970; worked great but not in motion.
H.
NQ5H