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Author Topic: Hustler Super Resonators  (Read 2531 times)
N5XTR
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Posts: 108




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« on: February 05, 2010, 07:55:56 PM »

I bought the supers for 20m 40m and 80m.
The bandwidth is better than the regular resonators.
They are BIG!
Here is a video...Enjoy!

http://www.youtube.com/watch?v=mew4FTc8N3M

Joel - N5XTR
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K0BG
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« Reply #1 on: February 06, 2010, 04:26:56 AM »

Joel, ask yourself a simple question. Why is the bandwidth increased when switching to the bigger coils?

The answer is; They are lossier than the smaller coils, mainly due to the large end caps used. In fact, if you remove the end caps, the Q almost doubles. Of course you can't drive around with them removed. And, the little coils as just fine, even with 600 watts PEP through them.
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N5XTR
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« Reply #2 on: February 06, 2010, 06:52:26 AM »

I respectfully disagree with you.  
The reason that they have more bandwidth is because of the diameter of the wire used in the coil.

No, the standard resonators will not handle 600 watts.  They are rated for 400 and my 40m standard resonator blistered because I put 600 watts to it.  The SWR was not high.  I do not run a tuner, only resonant antennas on my mobile.  If the SWR is over 1.5:1 (1:1.5 in ur language)I do not TX there.
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AA4PB
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« Reply #3 on: February 06, 2010, 06:54:51 AM »

Normally you would think that the Super sized is wound with larger guage wire, thus lower loss. What I've read however indicates that, as Alan said, the capacitance of the large end caps creates loss that overcomes the benefit of the larger wire. The larger Hustler coils actually have more loss than the smaller coils. The larger wire probably contributes to the wider bandwidth.
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KE3WD
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« Reply #4 on: February 06, 2010, 07:24:54 AM »

What is the 1:1 bandwidth of a 50 ohm resistor? 
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K0BG
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« Reply #5 on: February 06, 2010, 08:25:23 AM »

Bob told it like it is. There is another issue too, neither of us mentioned before.

An HF mobile antenna, of decent quality, properly mounted, and at resonance (Øj), will have an input impedance of about 25 ohms or so on the lower bands. Remembering that the resistive component varies more with frequency change than the reactive component does; when you tune the antenna off frequency, the SWR will appear to fall (get closer to 1:1). I think you should measure yours (resistive component at Øj, not the lowest SWR!).

Further, if you smoked a low power coil with 600 watts (even extended CW), chances are the coil had some water ingress; a common problem with Hustler coils. They do get warm after a few minutes of operation at this level, however. The larger coils don't exhibit heating as much, due mainly to their larger surface area.

Just so you'll know, the resistive Q losses between the large and small 80 meter coils measured at 3.7 MHz, is 48 ohms versus 20 ohms respectively. They keep the same approximate ratio on 40, 20, and 15.
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KE3WD
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« Reply #6 on: February 06, 2010, 08:56:56 AM »

Alan, did you see the condition of his original Hustler coils in the video? 


They are ready for the ebay "rarely used, only once to see if they worked" category...


It is not about the aerial anymore, it is about the power meter, unfortunately. 



"Have fun!"


The dfeinition of "fun" is ever changing...
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N5XTR
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« Reply #7 on: February 06, 2010, 09:31:03 AM »

This place is turning into a Bashfest.
WTF is with you guys?
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K0BG
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« Reply #8 on: February 06, 2010, 09:39:35 AM »

The issue here is, Joel, is not to bash anyone. If you take it as that, you're wrong. The real issue is, if you'll forget the directness, is to teach.

I'll tell you what. I live in Roswell, NM, about 190 miles from your FCC listed address. I'll be happy to make an appointment with you, and drive to Lubbock, to explain any facet you wish about mobile operation. The only thing I request in the interim is, spend some time on my web site. Read the Antennas, Commercial article, And the Antenna Efficiency article. They you'll have a better idea of the questions to ask. By the way, I'll even pay for lunch.

I'll be at the Midland, hamfest to, if you're going.

http://www.k0bg.com
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N5XTR
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« Reply #9 on: February 06, 2010, 11:35:39 AM »

I have read your site, and many of your posts.
I do plan to be in Midland for their hamfest.
I do realize that all antennas are a compromise.
Mobile antennas are an even more compromise, which is why I have an the amp.  However, I do have the capacity to think outside the ARRL antenna book and experiment with things that shouldn't work.
Now, you claim that the super resonators have more loss that the regular ones.  I tested that theory with 4 stations on 20m this morning.  Using the same power, I made first contact with the super and changed to the regular resonators.  Every contact noticed a signal loss on the regular resonators.  It wasn't much but it was there.  Mostly it was 1 s-unit loss on their end.  One station said I went from 40 over 9 to 30 over 9.  All of these QSO's were done from the same location, vehicle attitude, and stationary of course.  If you can explain why the higher loss results in a higher received signal, than buddy I'll buy you lunch at Midland.
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K0BG
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« Reply #10 on: February 06, 2010, 01:46:54 PM »

You can't judge an antenna by a log book. Here's a suggestion. Try the experiment again, but don't tell the other party which is which.

This reminds me of Tom Rusch's (W8JI) experiment between a dipole and a G5RV if he told folks that he was using a G5RV, the reports were almost always in favor of the dipole. When he told them the the opposite (the dipole was actually the G5RV, and visa versa) he got the sam results. When he just told the A or B, the vast majority couldn't tell the difference.

Of course, the real way is to do a field strength measurement. Although I personally have a few gripes about antenna shootouts, it's interesting to note the difference between the two coils. That info in on the 3905 site, and you can draw your own conclusions.
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N5XTR
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« Reply #11 on: February 06, 2010, 01:58:05 PM »

Actually I did NOT tell other other stations which resonator I was using.  Funny you should assume that.
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WX7G
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Posts: 5919




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« Reply #12 on: February 06, 2010, 03:22:22 PM »

I have both the RM80 and the RM80S resonators and yes the RM80S has more loss. I have measured them both on a VNA. They are quite lossy because they operate just about at self-resonance. The Super resonator is larger so that it can dissipate the extra power.

But given typical ground losses the resonator accounts for 1/2 to 2/3 of the total antenna loss in a mobile 75 meter antenna. 500 watts with the RM80S will produce more signal than 100 watts to the RM80. And the extra bandwidth of the RM80S is convenient. They made the RM80S (and other 'super' resonators) lossy for a reason.
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WX7G
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« Reply #13 on: February 06, 2010, 03:25:59 PM »

Remember Dave's rule of small antennas:

SMALL
EFFICIENT
WIDE BAND

PICK ANY TWO
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WX7G
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Posts: 5919




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« Reply #14 on: February 06, 2010, 03:40:16 PM »

N5XTR, one S-unit difference is huge. That is 6 dB and respresents a drop in radiation efficiency by a factor of 4 between the RM20S and the RM20. The 10 dB drop claimed by one station represents a 10X drop in efficiency. If true, the RM20 would exhibit 4 or 10 times the VSWR bandwidth of the RM20S. Does it?

As K0BG says antenna comparisons really require a field strength measurement to quantify things. In liu of that RECEIVE measurements of random stations can be used. There is no reason to run transmit measurements with other stations. The difficulty here is the time it takes to switch resonators. One way around this is to have a ham nearby - let's say a few hundred feet away - transmitting on another 20 meter mobile. Have him drop the power to obtain a convenient S-meter reading and have him run a carrier (CW). Note his signal strength. Now switch resonators and repeat. Do this several times and plot the data on graph paper. Which resonator gives the highest received signal strength? Note this is a relative measurement and does not rely on the accuracy of the S-meter in your radio. The answer we are looking for is a YES or NO as to which resonator gives the highest received signal.

As to the RM80S, it has a loss of 20 ohms near resonance. Add this to a 10 to 20 ohm ground loss and we have a nice 30 to 40 ohm load for the radio. Not such a bad VSWR. Given the radiation resistance of 1.5 ohms the radiation efficiency is but 4%. It works.
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