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Bigbob
| | Posted on Wednesday, January 01, 2003 - 10:24 am: | 
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This is one for all you antenna gurus,how tall or long would a wire antenna be for 11-meters,for harmonic opperation.Would a 160-meter 1/2 wave-dipole antenna work,would there be any gain over a 11-meter 1/2 wave-dipole,this would be skip only(horiz-polar),I know I would need twin-lead,a balun,and a good tuner,but despite the work and attention to detail,is there any advantage to this? |
Marconi
| | Posted on Wednesday, January 01, 2003 - 11:26 am: |
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Bob, I cannot answer your question, but you will probably need to get that one high and the radiation pattern for 11 meters would probably not be broadside to the wire. You would probably have many sharp lobes and nulls laying somewhat tangent to the wire in the direction of the ends. I figure it would act something like a long wire and may not be very effective. If you could control the feed of an end fed long wire, that might be more effective, even in 11 meters. Again, I am not sure.
I figure that if some of these exotic type antennas could be effectively scaled down to 11 meters we would be hearing about them in the 10-12 meter areas. There are likely unique properties working with very low frequencies. |
707
| | Posted on Wednesday, January 01, 2003 - 2:53 pm: |
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Take a look at these:
beverage1
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707
| | Posted on Wednesday, January 01, 2003 - 2:56 pm: |
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as for dipoles, assuming you are in an area that is DX accessible to me from SW Texas, gimme a time and date(either this afternoon or this weekend) and I'll give you acall so you can hear what a dipole will do with 12 watts. |
rharper
| | Posted on Wednesday, January 01, 2003 - 5:59 pm: |
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I've tried a multi-band ham dipole - 10,20,40,80 on 11-meters with a tuner. DX was great, but had results (DX) equal with my MACO V. |
Bigbob
| | Posted on Wednesday, January 01, 2003 - 6:26 pm: |
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This saturday after noon 1-4-03 |
707
| | Posted on Wednesday, January 01, 2003 - 9:19 pm: |
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OK, sounds good. I still don't know where you are located, so not sure if we will even have conditions. IN general, I get the east coast, and upper midwest til about 11a, then again at 1p til 5p CST. West coast and NW starts popping in about 3:30pm CST til about 5:30pm.
I'll be ready on ch38USB when you are, so let me know sort of where you are so I can plan. |
de
| | Posted on Thursday, January 02, 2003 - 8:03 am: |
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Check my math. What you are looking for is a longwire antenna. This is one that is a odd multiple quarterwave length.
A half wave length of 27.365 mhz is right at 17 feet (468/27.365). An 80 meter half wave of 3.935 mhz is 119 feet (468/3.935). This is length of 119 feet is 7 half wave lengths (17 x 7). An odd number quarter wave lengths on each side of a center fed dipole. HOWEVER the feed point impedance will not be 50 ohms. You probably will have to use a tuner or some kind of Inductor Cap circut at the antenna feed point if you wanted to use the antenna just on the CB bands.
I hope I did not confuse you.
So in theory a wire half wave dipole fed in the middle would work on both the upper parts of the CB band PLUS 80 meters. On 80 meters the gain would be minimal at best as half wave dipoles do not have gain. BUT on 27 mhz there would be/should be a half decent utility gain given that the muliple quarter wave length is 7. You would have to use a modeling program to test transmission patterns and determine gain figures.
I do know that I can use my 80 meter inverted V on 10 and CB effectively with just a little tuner action on 10 meters. |
Bigbob
| | Posted on Thursday, January 02, 2003 - 8:21 am: |
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Traversecity, Michigan near the base of the little finger of the mitt,lower penninsula. |
Buck
| | Posted on Thursday, January 02, 2003 - 1:12 pm: |
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say bigbob....this is a little off subject but whatever happened to mitch rompalla and the new world record buck he supposedly shot a few years ago?????? something was awfully fishy about that deal |
Bigbob
| | Posted on Saturday, January 04, 2003 - 8:51 am: |
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Buck,never heard of him,sorry.Please tell us the story if you got time,many of us are interested in things beside radio,but for the moderators sake keep it short,thanks.Bigbob |
707
| | Posted on Saturday, January 04, 2003 - 1:37 pm: |
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bigbob- good sounding station. Funny how DX works. The station I was talking to when you got in there was in Kentucky running a Galaxy 88 in his mobile and we were talking for about 15 minutes with no prob. The band is way crowded today! |
707
| | Posted on Saturday, January 04, 2003 - 1:45 pm: |
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bigbob- I must have not gotten your email correctly. you can check my personal page here or just go to http://www.dxring.net and use the email link there or on the 707 page to contact me.
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N8fgb
| | Posted on Saturday, January 04, 2003 - 9:37 pm: |
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I fyou use an 80 meter 1/2 wave dipole on 11 meter it will radiate off the ends.You will have best results with balanced feedline and a tuner.I have used this myself in the past.
Rich |
Buck
| | Posted on Sunday, January 05, 2003 - 5:20 am: |
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well for those interested in hunting, take a look here.....its an old story from 98. Sounds and looks very fishy!!!!!!!!
http://www.freep.com/sports/outdoors/qdeer201.htm |
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