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Author Topic: Vertical & 1.5Kw VS Tribander & 200w  (Read 5501 times)
AF3Y
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« Reply #15 on: January 09, 2013, 09:50:57 AM »

I rarely turn on the amp for most of my DXing. The 100w and the MonstIR at 75' beats out a lot of guys running a tribander and 1.5kw.
Not to mention being 875' ASL and having a great takeoff angle over about 270 degrees.

The good old hills of Sussex County. Grew up there and graduated from Newton H.S. Worked in Franklin, NJ soldering military solid state tube replacement parts at a place called "Tymac Controls" during the summers when I first went to college - and before my family moved to the SF Bay Area - half way through college.

People don't realize how nice NJ can be . . .

Hmmm.... I almost married a lady from Franklin, NJ. (Then I wised up. hi )

Worked up there for a couple years. Best peaches I ever ate, and best Italian food ever at a sort of diner in Netcong(?). Cant remember name of the diner, but yeah, it was good.

73, Gene AF3Y
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AA6YQ
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« Reply #16 on: January 09, 2013, 11:10:19 AM »

OK, here is your math problem for today.  

Ham "A" is in Key West, Florida, running 1500 Watts to a 1/4 wave vertical with 36 radials of varying lengths.

Ham "B" is down the street from "A", a few hundred yards. He is running barefoot, 200 watts to a Force 12 Tri-bander up around 100 feet.

Assuming both these guys want to work BS7, WHICH One is going to put the most power in the ears of the ISOTROPE on Scarborough?

Obviously, assume all prop, condx, etc. to be equal for the comparison.

Ham A's vertical is one-quarter wavelength for what band? Does ham A have a way to tune this antenna for multiple bands? If so, for which ones, and with what efficiencies relative to its primary band?
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N5UD
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« Reply #17 on: January 09, 2013, 12:28:30 PM »

OK, here is your math problem for today.  

Ham "A" is in Key West, Florida, running 1500 Watts to a 1/4 wave vertical with 36 radials of varying lengths.

Ham "B" is down the street from "A", a few hundred yards. He is running barefoot, 200 watts to a Force 12 Tri-bander up around 100 feet.

Assuming both these guys want to work BS7, WHICH One is going to put the most power in the ears of the ISOTROPE on Scarborough?

Obviously, assume all prop, condx, etc. to be equal for the comparison.

Ham A's vertical is one-quarter wavelength for what band? Does ham A have a way to tune this antenna for multiple bands? If so, for which ones, and with what efficiencies relative to its primary band?


Well I was wondering when someone would ask that question ?
1/4 wave on which band ? Since it is Key West, is vertical mounted on the beach for saltwater effect ? Then we might ask, again depending on band, short path or long path ?

1.5 KW output sure is a lot of RF.

100 feet up with a yagi should get a low angle. Vertical on the beach should too. Is the Scarborough station using verticals ?

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AF3Y
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« Reply #18 on: January 09, 2013, 03:06:45 PM »


Ham A's vertical is one-quarter wavelength for what band? Does ham A have a way to tune this antenna for multiple bands? If so, for which ones, and with what efficiencies relative to its primary band?


OK, lets say quarter wave for 40 meters, may be tuned for 80m thru 10 meters with auto tuner.

Antenna not near ocean, perhaps a couple miles away. IF you can get that far from the ocean in Key West.... (??)

That help you any? What efficiencies relative to the 40m band? I dont have a clue Roll Eyes.
73, Gene AF3Y
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AA6YQ
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« Reply #19 on: January 09, 2013, 08:21:25 PM »


Ham A's vertical is one-quarter wavelength for what band? Does ham A have a way to tune this antenna for multiple bands? If so, for which ones, and with what efficiencies relative to its primary band?


OK, lets say quarter wave for 40 meters, may be tuned for 80m thru 10 meters with auto tuner.

Antenna not near ocean, perhaps a couple miles away. IF you can get that far from the ocean in Key West.... (??)

That help you any? What efficiencies relative to the 40m band? I dont have a clue Roll Eyes.


I suggest that you use an antenna modeling application to see what sort of pattern and gain results when using the 40m vertical on other bands. I suspect that you will be disappointed.

So the choice is a 40m vertical over a mid-range ground screen with 1500 watts vs. a competent tribander at 100' with 200 watts.

Your question was "which antenna will produce the loudest signal at BS7?" If your goal is to work BS7, that's the wrong question. As I posted in another thread, "you can't work what you can't hear". The right question is "which antenna will maximize my opportunities to hear the BS7 station?" When receiving, vertical antennas are susceptible to man-made noise. The tribander gives you gain, QRM and QRN rejection to the sides and back, the ability to exploit long-path openings, and all of this on three different bands -- at least one of which (20m) should produce good openings even when the solar flux is at the low end of its recent range.

I'd want the tribander.

     73,

           Dave, AA6YQ
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AF3Y
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« Reply #20 on: January 10, 2013, 04:49:39 AM »

Your question was "which antenna will produce the loudest signal at BS7?" If your goal is to work BS7, that's the wrong question. As I posted in another thread, "you can't work what you can't hear".
I'd want the tribander.

     73,
 Dave, AA6YQ

Dave, I understand what you have said above, and I basically have to agree with you, BUT..... for what its worth, right or wrong, my question was
"which antenna will produce the loudest signal at BS7?" (should have said, which station will produce the loudest signal at BS7?)

73, Gene AF3Y
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WB3BEL
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« Reply #21 on: January 10, 2013, 08:11:57 AM »

This is not a math problem...

I am not even sure the problem statement is defined clearly enough to give a single answer if there was one.

As I understand it:
Ham A ~30 ft vertical with 36 radials and 1500W.  Location = Key West but more than mile from ocean if possible...
Ham B Force12 Tribander at 100ft and 200W.  Location = within few hundred yards of A.

Outcomes:
Frequency of operation 14,21,28MHz.  Almost all of the time B will be louder at BS7.  Way louder and hear better as well.  How much louder may depend on the specific F12 antenna model and the actual band used.

Frequency of operation 18 or 24 MHz. A might be louder but probably would not hear as well.   Station A being louder requires the autotuner to be close to the vertical or some low loss transmission line system.  Might be a bit tricky at 1500W...

Frequency of operation below 14MHz.  I doubt this is the scenario, but if it is then most likely A is louder on 80,40 or 30 meters.  If B can load the tower as vertical on the lower bands and has a good ground system it might be close on 80m.  If the band was 160m, (unlikely) and B had tower fed as a vertical then B would be many dB louder.

But at the last BS7 activation most of the east coast QSOs were above 14 MHz.  Sunspots were lower then but 14MHz was a good choice.  Maybe if it was now, 15m might be stronger.  I'd still want the yagi at 100 ft...

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N2RJ
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« Reply #22 on: January 10, 2013, 08:48:01 AM »

BS7H was using a BiggIR vertical from Fluidmotion SteppIR.
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W2IRT
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« Reply #23 on: January 10, 2013, 09:34:08 AM »

BS7H was using a BiggIR vertical from Fluidmotion SteppIR.
One station was using a small yagi (A C3SS, I believe).
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KY6R
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« Reply #24 on: January 10, 2013, 10:12:39 AM »

Frequency of operation below 14MHz.  I doubt this is the scenario, but if it is then most likely A is louder on 80,40 or 30 meters.  If B can load the tower as vertical on the lower bands and has a good ground system it might be close on 80m.  If the band was 160m, (unlikely) and B had tower fed as a vertical then B would be many dB louder.

The ham that can afford a 100 foot tower with Force-12 yagi would probably have 4 squares on 80 and 40M and even a decent vertical on 160M. Maybe even yagi's on 40 and 30M - up at least 1/2 wl.

Hams that go to that bother with 100 foot towers are WAY more OCD than I am about ham radio and DX-ing.
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WS3N
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« Reply #25 on: January 10, 2013, 10:23:32 AM »

Yes, but Ruth hit 60 in only 154 games.  Grin



I don't have to check the cluster to know that there's not much on.
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N4OGW
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« Reply #26 on: January 10, 2013, 10:58:57 AM »


Hams that go to that bother with 100 foot towers are WAY more OCD than I am about ham radio and DX-ing.

I thought that too before I put up my 100 foot tower (and 66 foot tower) Smiley Actually, if you have the space, putting up
a 100 foot guyed tower is not hard. And you will find out that maintaining the tower and yagi takes MUCH less time
than say maintaining a collection of wire antennas in trees (what I did before and still partially do).

I did work BS7H on 40, 20, and 15 from here (MS). The 15m CW qso was really lucky and I still don't understand what the
propagation mechanism was. Remember in 2007 solar conditions were way down. Listening to the stations they worked on 15,
they were all in this general part of the country (MS, AR, LA, east TX). Normally if 15m is open to Asia, the W6's will crush us.
But I didn't hear them work any west coast stations- at first I thought it had to be a pirate. The beam heading seemed to be the
normal short-path direction.

Tor
N4OGW/5
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AA6YQ
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« Reply #27 on: January 10, 2013, 05:08:49 PM »

Your question was "which antenna will produce the loudest signal at BS7?" If your goal is to work BS7, that's the wrong question. As I posted in another thread, "you can't work what you can't hear".
I'd want the tribander.

     73,
 Dave, AA6YQ

Dave, I understand what you have said above, and I basically have to agree with you, BUT..... for what its worth, right or wrong, my question was
"which antenna will produce the loudest signal at BS7?" (should have said, which station will produce the loudest signal at BS7?)


Which antenna will produce the loudest signal at BS7 will depend on propagation. When 10m is open, 50w can produce an S9 signal half way around the world. When the solar flux is in the toilet, not even 20m will be open, but a 40m grey line path can produce loud signals, with the 1500w compensating for absorption.
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AA6YQ
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« Reply #28 on: January 10, 2013, 05:10:43 PM »

Hams that go to that bother with 100 foot towers are WAY more OCD than I am about ham radio and DX-ing.

"Nothing so much needs reforming as other people's habits"

   Mark Twain.
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KY6R
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« Reply #29 on: January 10, 2013, 06:44:53 PM »

Hams that go to that bother with 100 foot towers are WAY more OCD than I am about ham radio and DX-ing.

"Nothing so much needs reforming as other people's habits"

   Mark Twain.

another way of saying "jealousy", and you better believe I'm jealous of a 100 AND a 60 foot tower.

Good one!
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