mobile antenna impedance comparison
 

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.
The screwdriver shows encouraging results for signal improvement over the
others on 80 and 40.
Seems the diameter of that bottom conductor on the screwdriver makes a big
difference at the lower frequencies.
Since the TS-480HX has two antenna jacks, I think an additional small
screwdriver is in order; One for 80-20; One for 20-6.
73
H.
NQ5H

Nice numbers, Adam. I'm only interesetd in the Hustler. Are these all
with very small reactance?--That is, insignificant relative to the real
part?

I haven't measured yet, but this says that on 40 we have a 2 : 1 SWR and on
80 it is about 2.4 : 1...?

Please indicate how you got these numbers.

What vehicle ?
Where is the antenna mounted ?
What type of antenna mount ?
How is the feed line shield connected to the vehicle ? (I put a jumper from
the mount "ground" to the trunk lid to get rid of 20M flakies.)
How did you measure them -- assuming they are measured...?
--
Steve N, K,9;d, c. i My email has no u's.

"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.
The screwdriver shows encouraging results for signal improvement over the
others on 80 and 40.
Seems the diameter of that bottom conductor on the screwdriver makes a big
difference at the lower frequencies.
Since the TS-480HX has two antenna jacks, I think an additional small
screwdriver is in order; One for 80-20; One for 20-6.
73
H.
NQ5H

Hi Steve

"Steve Nosko" wrote in message
...
Nice numbers, Adam. I'm only interesetd in the Hustler. Are these all
with very small reactance?--That is, insignificant relative to the real
part?

I haven't measured yet, but this says that on 40 we have a 2 : 1 SWR and
on
80 it is about 2.4 : 1...?

Please indicate how you got these numbers.

What vehicle ?
Dodge Durango

Where is the antenna mounted ?
Ball mount on the right rear where you can get at the back from in the car.

What type of antenna mount ?
ball

How is the feed line shield connected to the vehicle ? (I put a jumper
from
the mount "ground" to the trunk lid to get rid of 20M flakies.)
Coax connector of the ball mount and 2" copper strap. Feed is less than 1
foot.

How did you measure them -- assuming they are measured...?

MFJ analyzer measured R at resonance (reactance is zero)
I then use a toroidal autoformer to get 50 ohms.
73
H.
NQ5H

--
Steve N, K,9;d, c. i My email has no u's.

"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.
The screwdriver shows encouraging results for signal improvement over
the
others on 80 and 40.
Seems the diameter of that bottom conductor on the screwdriver makes a
big
difference at the lower frequencies.
Since the TS-480HX has two antenna jacks, I think an additional small
screwdriver is in order; One for 80-20; One for 20-6.
73
H.
NQ5H

Doesn't; the Screwdriver's low feedpoint impendence mean it will be less
efficient not more?
--
Radio K4ia
Craig "Buck"
Fredericksburg, VA USA
FISTS 6702 cc 788 Diamond 64
"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.
The screwdriver shows encouraging results for signal improvement over the
others on 80 and 40.
Seems the diameter of that bottom conductor on the screwdriver makes a big
difference at the lower frequencies.
Since the TS-480HX has two antenna jacks, I think an additional small
screwdriver is in order; One for 80-20; One for 20-6.
73
H.
NQ5H

No
It means there is less loss resistance.
The radiation resistance on 80 and 40 of all these short antennas is tiny, a
very few ohms.
At resonance the measured resistance is the sum of radiation and loss
resistance.
Matching the impedance at resonance results in the greatest measured field
strength, at least in my front pasture;
So making the antenna resonant, then matching the impedance, is my preferred
approach.
Using reactances to do that is the same as the bazooka antenna: storing
energy in tank circuits; A lossy enterprise.
Funny thing about this stuff, I built my first crystal set in 1956, my first
transmitter in 1961 and I'm not bored yet.
73
H.
NQ5H

"Craig Buck" wrote in message
news:ZT1Pb.4811$ZJ1.4783@lakeread01...
Doesn't; the Screwdriver's low feedpoint impendence mean it will be less
efficient not more?
--
Radio K4ia
Craig "Buck"
Fredericksburg, VA USA
FISTS 6702 cc 788 Diamond 64
"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.
The screwdriver shows encouraging results for signal improvement over
the
others on 80 and 40.
Seems the diameter of that bottom conductor on the screwdriver makes a
big
difference at the lower frequencies.
Since the TS-480HX has two antenna jacks, I think an additional small
screwdriver is in order; One for 80-20; One for 20-6.
73
H.
NQ5H

I was talking about radiation efficiency taking into account the ground
losses. The ARRL Antenna Book equation is Efficiency = Radiation Resistance
divided by the sum of Radiation Resistance + Ground loss + Coil loss. Plug
in a 6 ohm ground loss and whatever you want to assume for the coil loss.
The higher the radiation resistance the higher the efficiency. No?
--
Radio K4ia
Craig "Buck"
Fredericksburg, VA USA
FISTS 6702 cc 788 Diamond 64
"H. Adam Stevens" wrote in message
...
No
It means there is less loss resistance.
The radiation resistance on 80 and 40 of all these short antennas is tiny,
a
very few ohms.
At resonance the measured resistance is the sum of radiation and loss
resistance.
Matching the impedance at resonance results in the greatest measured field
strength, at least in my front pasture;
So making the antenna resonant, then matching the impedance, is my
preferred
approach.
Using reactances to do that is the same as the bazooka antenna: storing
energy in tank circuits; A lossy enterprise.
Funny thing about this stuff, I built my first crystal set in 1956, my
first
transmitter in 1961 and I'm not bored yet.
73
H.
NQ5H

"Craig Buck" wrote in message
news:ZT1Pb.4811$ZJ1.4783@lakeread01...
Doesn't; the Screwdriver's low feedpoint impendence mean it will be
less
efficient not more?
--
Radio K4ia
Craig "Buck"
Fredericksburg, VA USA
FISTS 6702 cc 788 Diamond 64
"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.
The screwdriver shows encouraging results for signal improvement over
the
others on 80 and 40.
Seems the diameter of that bottom conductor on the screwdriver makes a
big
difference at the lower frequencies.
Since the TS-480HX has two antenna jacks, I think an additional small
screwdriver is in order; One for 80-20; One for 20-6.
73
H.
NQ5H

"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

I played with the Hustler when it was introduced, and got the impression it
was a loser 40 years ago. I now wonder if that lower mast is purposely
lossy. Or maybe just accidentally lossy and they ran with it. Looks good
on SWR meters which hams are infamous for. I would modify your observation
about the diameter of the bottom section to: The RF impedance of the lower
section really counts. How about trying either a copper braid or tube
around the Hustler or a copper plated base section under the bug catcher and
see what that measures.

--
Crazy George
Remove N O and S P A M imbedded in return address
"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.
The screwdriver shows encouraging results for signal improvement over the
others on 80 and 40.
Seems the diameter of that bottom conductor on the screwdriver makes a big
difference at the lower frequencies.
Since the TS-480HX has two antenna jacks, I think an additional small
screwdriver is in order; One for 80-20; One for 20-6.
73
H.
NQ5H

Building an antenna using a big copper pipe for the base is appealing.
It's the motor tune feature on 80 that attracted me to the screwdriver.
All a low SWR insures is that you aren't heating up your transmitter.
I use a field strength meter.
73
H.

"Crazy George" wrote in message
...
I played with the Hustler when it was introduced, and got the impression
it
was a loser 40 years ago. I now wonder if that lower mast is purposely
lossy. Or maybe just accidentally lossy and they ran with it. Looks good
on SWR meters which hams are infamous for. I would modify your
observation
about the diameter of the bottom section to: The RF impedance of the
lower
section really counts. How about trying either a copper braid or tube
around the Hustler or a copper plated base section under the bug catcher
and
see what that measures.

--
Crazy George
Remove N O and S P A M imbedded in return address
"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.
The screwdriver shows encouraging results for signal improvement over
the
others on 80 and 40.
Seems the diameter of that bottom conductor on the screwdriver makes a
big
difference at the lower frequencies.
Since the TS-480HX has two antenna jacks, I think an additional small
screwdriver is in order; One for 80-20; One for 20-6.
73
H.
NQ5H

Craig Buck wrote:
I was talking about radiation efficiency taking into account the ground
losses. The ARRL Antenna Book equation is Efficiency = Radiation Resistance
divided by the sum of Radiation Resistance + Ground loss + Coil loss. Plug
in a 6 ohm ground loss and whatever you want to assume for the coil loss.
The higher the radiation resistance the higher the efficiency. No?

For an 8 ft center-loaded whip on 75m, the ARRL Antenna Book gives 0.8 ohms
as the radiation resistance and 22 ohms as the feedpoint impedance. That's
an efficiency of about 3.6%, about 4 watts radiated for 100 watts input.
--
73, Cecil http://www.qsl.net/w5dxp



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Cecil Moore wrote:

Craig Buck wrote:

I was talking about radiation efficiency taking into account the ground
losses. The ARRL Antenna Book equation is Efficiency = Radiation
Resistance
divided by the sum of Radiation Resistance + Ground loss + Coil loss.
Plug
in a 6 ohm ground loss and whatever you want to assume for the coil loss.
The higher the radiation resistance the higher the efficiency. No?


For an 8 ft center-loaded whip on 75m, the ARRL Antenna Book gives 0.8 ohms
as the radiation resistance and 22 ohms as the feedpoint impedance. That's
an efficiency of about 3.6%, about 4 watts radiated for 100 watts input.

Keeping Ground Loss and Coil Loss constant and increasing the radiation
resistance from 0.8 ohms to 1.6 ohms changes the efficiency to 7%. Hmmm
.... the higher the radiation resistance the higher the efficiency!!

"Dave Shrader" wrote in message
news:hBdPb.92880$nt4.225549@attbi_s51...
Cecil Moore wrote:

Craig Buck wrote:

I was talking about radiation efficiency taking into account the ground
losses. The ARRL Antenna Book equation is Efficiency = Radiation
Resistance
divided by the sum of Radiation Resistance + Ground loss + Coil loss.
Plug
in a 6 ohm ground loss and whatever you want to assume for the coil
loss.
The higher the radiation resistance the higher the efficiency. No?


For an 8 ft center-loaded whip on 75m, the ARRL Antenna Book gives 0.8
ohms
as the radiation resistance and 22 ohms as the feedpoint impedance.
That's
an efficiency of about 3.6%, about 4 watts radiated for 100 watts input.

Keeping Ground Loss and Coil Loss constant and increasing the radiation
resistance from 0.8 ohms to 1.6 ohms changes the efficiency to 7%. Hmmm
... the higher the radiation resistance the higher the efficiency!!

In all the cases I reported the antennas were on the same ball on the same
truck: ground losses were a constant.
They were all of comparable length, the Hustler a bit shorter than the
screwdriver, the bugcatcher a bit longer, but comparable radiation
resistances; about an ohm.
The lower the loss resistance the higher the efficiency, which gets back to
the ~10 ohms of the screwdriver;
Comparing that to the ~20 ohms of the Hustler and bugcatcher leads me to
suspect the difference is in the loss resistance which is consistent with
observed performance on the air.
With my 200 watt mobile rig I should radiate about 16 watts on 80!
;^)
73
H.
NQ5H

H. Adam Stevens, NQ5H wrote:
Comparing that to the ~20 ohms of the Hustler and bugcatcher leads me to
suspect the difference is in the loss resistance which is consistent with
observed performance on the air.

There's something wrong with the bugcatcher feedpoint impedance
unless there was a matching coil, cap, or transformer at the base.
Did you have any coils shorted out on the loading coil for tuning
purposes? Shorted coils lower the Q.
--
73, Cecil http://www.qsl.net/w5dxp



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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



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"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
...
H. Adam Stevens, NQ5H wrote:
Comparing that to the ~20 ohms of the Hustler and bugcatcher leads me to
suspect the difference is in the loss resistance which is consistent
with
observed performance on the air.

There's something wrong with the bugcatcher feedpoint impedance
unless there was a matching coil, cap, or transformer at the base.
Did you have any coils shorted out on the loading coil for tuning
purposes? Shorted coils lower the Q.
--
73, Cecil http://www.qsl.net/w5dxp



Nope
Just the Hustler base, the entire bugcatcher coil and a 103 " whip.
I expected it to be lower in impedance at resonance.
Now I've ordered a BBS screwdriver to see if the copper base is better than
aluminum.
Copper has about a tenth the resistance of aluminum, we shall see.
H.
NQ5H

H. Adam Stevens, NQ5H wrote:
Just the Hustler base, the entire bugcatcher coil and a 103 " whip.
I expected it to be lower in impedance at resonance.

What bugcatcher coil was it? Obviously not the big one. Is the
Hustler base the one that hinges? If so, it might not be
conducting properly.
--
73, Cecil http://www.qsl.net/w5dxp



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Yes it is the "big one" but I suspect that, since I cobbled it together,
that R is a big issue.
I don't care since it isn't a realistic solution. I used it "parked mobile"
in 1970.
Comparing the Nott with the Tarheel should be fun.
H.
NQ5H


"Cecil Moore" wrote in message
...
H. Adam Stevens, NQ5H wrote:
Just the Hustler base, the entire bugcatcher coil and a 103 " whip.
I expected it to be lower in impedance at resonance.

What bugcatcher coil was it? Obviously not the big one. Is the
Hustler base the one that hinges? If so, it might not be
conducting properly.
--
73, Cecil http://www.qsl.net/w5dxp



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H.,
When you find out that the aluminum/copper base
makes no difference at all, can I have the one you
don't want?
'Doc

"Cecil Moore" wrote in message
...
H. Adam Stevens, NQ5H wrote:
Just the Hustler base, the entire bugcatcher coil and a 103 " whip.
I expected it to be lower in impedance at resonance.

What bugcatcher coil was it? Obviously not the big one. Is the
Hustler base the one that hinges? If so, it might not be
conducting properly.
--
73, Cecil http://www.qsl.net/w5dxp


Yes it's the big one; I suspect dirt in the threads.
It's an impractal monster anyway.
73
H.

"'Doc" wrote in message ...
H.,
When you find out that the aluminum/copper base
makes no difference at all, can I have the one you
don't want?
'Doc

So you have done the measurements?
And no, I'm gonna run two screwdrivers; Then I can talk to myself.
;^))))))))))
H.

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

"Crazy George" wrote in message ...
I played with the Hustler when it was introduced, and got the impression it
was a loser 40 years ago. I now wonder if that lower mast is purposely
lossy. Or maybe just accidentally lossy and they ran with it. Looks good
on SWR meters which hams are infamous for.

The hustlers I tried had pretty lossy coils. I've never seen any
problems with the solid masts, but I've never tried the folding type.
In theory, they should be ok also, unless they have a problem with
dirt or corrosion. But the coils....
I hate those things....I once did a comparison using a large 80m
resonator against the coil on my homebrew plastic bugcatcher. It wuz
ugly...My homebrew coil was much less lossy. I'll never use a hustler
coil for anything serious. And being I'm always serious, that means
never... :/ MK