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Message |
    
Wolverine
Intermediate Member
Username: Wolverine
Post Number: 178
Registered: 2-2003
| | Posted on Friday, April 16, 2004 - 2:41 am: | 
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I just wanted a few opinions. I've reading about the "Capture Area" of antennas that can make or enhance efficiency in as far as recieving and transmitting. My question is, when it comes to shooting skip barefoot, will the big coil antennas, because of the larger capture area, out do traditional antennas like the Wilson 1000, K-40, and firesticks? Your answers are appreciated.
Wolverine. |
Mikefromms
Intermediate Member
Username: Mikefromms
Post Number: 147
Registered: 6-2003
| | Posted on Friday, April 16, 2004 - 12:35 pm: |
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Big coils are so you can run big power. Capture area or effect has to do with FM, if my memory serves me correctly.
For better skip or even local talking the lower takeoff angle is what you are looking for. The 5/8's wave antenna is the best choice because it offers the lowest angle of takeoff and the best position for it is in the center of the cab or roof of the car. I know it is difficult to do all the best things. However, when the conditions are right, you can shoot skip on a coathanger. LOL. Maybe one of the techs can give you some more concrete information. Any of the antennas mentioned are great, but the Wilson 1000, 5000 have been shown to outperform the K-40, and Firestick 5/8's (the 7 footer) gets rave reviews.
mikefromms
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Bruce
Senior Member
Username: Bruce
Post Number: 1155
Registered: 9-2003
| | Posted on Friday, April 16, 2004 - 8:18 pm: |
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Capture Area ( simply it is a bit more complex) is the amount of antenna exposed to radio waves ...... a 1/4 wave on 2 meters in only 19 inches but a 1/4 wave on 75 meters is 67 FEET! SO even if EACH is a great antenna the 75 meter one has 50 TIMES the wire lengh to " CAPTURE " a radio signal This is one reason why it is best on 6 meters and up to use a gain antenna on 2 and up 6 db gain verticals using 2 or more 5/8 waves stacked are common. PERSONALY i like a 5/8 wave on 6 and 2 for most fm work right now im using a colinear (3) 5/8 waves stacked on 2 meters and (6) 5/8 waves stacked on 440 it is 17 foot tall ! As for a 7 foot 5/8 wave on 11 meters i dont see how you can compress a 5/8 wave ( 25 foot) down to 7 and it work any better than a 7 foot loaded wip. |
Wolverine
Intermediate Member
Username: Wolverine
Post Number: 179
Registered: 2-2003
| | Posted on Saturday, April 17, 2004 - 6:50 am: |
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Thanks Mikefromms and Bruce, for the very informative answers. I've been eyeballing the purchase of a 10k antenna to compare with my other antennas, the 55 coil included. You know you have the "Bug" to purchase the latest antennas, even though your friends will say "Be happy with what ants that you already have", which by the way, includes the Wilson 5000 and Anttron 1700". What's wrong with me? I'm going to start taking their, and everyone's advice, and just be happy.
Wolverine. |
Kc0gxz
Advanced Member
Username: Kc0gxz
Post Number: 748
Registered: 3-2003
| | Posted on Saturday, April 17, 2004 - 3:00 pm: |
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Bruce
You said and I quote, "As for a 7 foot 5/8 wave on 11 meters i dont see how you can compress a 5/8 wave (25 foot) down to 7 and it work any better than a 7 foot loaded whip".
Bruce, unless I'm missing something in your statement, a 7ft 5/8 wave "IS" and "HAS" to be loaded if it's going to work in the CB band.
Am I misunderstanding you?
--------------------------------
By the way, if memory serves me correctly, the 7ft Firestik is advertized as a 3/4 wave - whatever the heck that is. Your thoughts on this would be appreciated also.
Jeff. |
Mikefromms
Intermediate Member
Username: Mikefromms
Post Number: 149
Registered: 6-2003
| | Posted on Saturday, April 17, 2004 - 4:41 pm: |
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Wolverine, with some people it is cars, guns and houses; with us, it's radios, antennas and amps. What a great hobby! I'm wanting an Imax 2000 with g/p kit now. Trying different stuff is part of the fun of the hobby. And copper is here to provide us with whatever we need.
mikefromms |
Ozzie
Intermediate Member
Username: Ozzie
Post Number: 177
Registered: 11-2003
| | Posted on Sunday, April 18, 2004 - 9:05 am: |
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Over the years I have learnt that there really is no such animal as the best antenna - one antenna that works in one location may be a dismal failure 200 yards up the road.
An example of this - several years back I lived in the bottom of a valley (bowl shaped) and I experimented with many 2m antennas. One of which was virtually a vertically mounted longwire. This antenna was next to useless to work my local repeater (about 10 miles away) but worked the ones in Sydney (120miles away) daily. It also worked great when talking to MIR. I gave the antenna to a just licenced friend, who lived around 5 miles away but outside of the valley. Grahame could work Sydney, Taree (100miles) and all the local repeaters with a full quieting signal. Now adays I use a Ringo Ranger on 2m at 25 ft - soon to be 50ft when I get the tower up.
Here I use a B & W folded dipole for HF that works well. The guy I got it off lives half a mile away and could not get much success from it.
Why the difference?? Location, mounting, whats around you - all these factors play a part in how well or badly any antenna will work. Try several types and you'll find some work well for you when others have had no luck with them.
Having said all this I always try to use antennas with the minimum (read none if possible) amount of loading coils and/or traps. Why? Fulllenght antennas will almost always work better than a shortended one will. |
Kc0gxz
Advanced Member
Username: Kc0gxz
Post Number: 753
Registered: 3-2003
| | Posted on Sunday, April 18, 2004 - 3:03 pm: |
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Best antenna for working DX? There is no such beast!!
1/4 waves - 1/2 waves - 5/8 waves or any wavelength for that matter, have a different radiation angle and during skip (DX) conditions, their different take-off pattern all hit the ionisphere at a different angle. In otherwords, when working DX, you could use a tuned coathanger tied in a tree and still easily communicate with another station hundreds or thousands of miles away.
No matter what their claims may be, antenna manufactures DO NOT build antennas for the sole purpose of working DX because conditions CONSTANTLY" change.
Lets put this in another perspective. By now most everyone knows that a 5/8 wave (base or mobile)antenna is king of the hill (providing it has some desent length to it) when it comes to (what we'll call) locale-long distance rag chewing. Its wave pattern just loves to hug the earth at a longer distance.
BUT, on some days when "conditions" are up, you may find that your top-of-the-line-big-dollar-kick-a$$ 5/8 wave antenna just ain't doin the job it usually does. And on that same day you discover that the tuned coathanger you have in the tree is working wonders for you that particular day. Why is this you wonder. It all depends on what the "conditions" favor.
I'll be the first to admit that it is a little disheartening to see a homemade wire antenna hanging in a tree outperform a big dollar vertical. But that's what makes working DX so exciting. You never know what's going to work the best on any given day when the skip is up. There are just too many varibles.
During skip conditions, there is no "best" antenna. I have an I-Max 2K with around 20 feet of mast under it on a 60 foot tower. And there are times when someone else across town can hit and hear the same DX station better than I can using 1/3 of my heigth with and using a different wavelength. And some days it's just the opposite. LOL. Isn't working DX fun?
Read Ozzies, post again. He wasn't talking about working skip, but the same theory appliys. What works at one station at any given time doesn't mean it will work well for another station under the same conditions.
(Good post Ozzie).
Jeff, kc0gxz. |
Wolverine
Intermediate Member
Username: Wolverine
Post Number: 180
Registered: 2-2003
| | Posted on Sunday, April 18, 2004 - 6:09 pm: |
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Excellent posts. Mikefromms point really hit home.
KcOgxz and Ozzie, you're both spot on. I feel like a gambler, trying to "Kick" the habit. But, I'm still having fun with all this, and I now, I've got my eyes on whatever kind of TVI no name, thing of mjig filter, that tech 808 is using in his ponderosa radio photos. I'm off da key!
Wolverine. |
Wolverine
Intermediate Member
Username: Wolverine
Post Number: 181
Registered: 2-2003
| | Posted on Saturday, April 24, 2004 - 4:32 am: |
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Berate me if you want to, but I have ordered the 10k mobile antenna, which is on it's way as I post, (to the disdain of my CB friends). I guess I'm a performance antenna collector of sorts, and I love to experiment. Any thoughts on Signal Engineering's flatside/Horizontal mobile antennas? Specifically the Goldenrod 45 Spyder(4.5 dbi gain), and the Goldenrod 50 (3.5 dbi gain). Should I add one of these antennas to my collection, whether or not the advertised gains, are to good to be true? I was taught that any mobile vertical antenna, big coil or not, have zero gain, no matter how it was constructed. When I die, I'm taking all of my antennas and CB gear with me. "I've got money to burn, for now". So your opinions are appreciated.
Wolverine. |
Tech833
Moderator
Username: Tech833
Post Number: 651
Registered: 8-2002
| | Posted on Saturday, April 24, 2004 - 12:57 pm: |
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Wolverine,
I have yet to see an mobile CB antenna with any gain over 1/2 wave dipole. It does not exist.
Coils do not add to the capture area of an antenna. Only actual radiating space counts.
The SE Spyder will outperform the 10K. A 1/4 wave whip will outperform them both. Yes, capture area.
For the same capture area of a loaded whip, getting the coil furthest away from the base will gain the most performance.
Capture area is not the only factor. For CB, a 70 foot wire has more capture area than a 1/2 wave dipole, yet the dipole will outperform the 70 foot wire. Gain becomes more important than capture ratio once the antenna gets over 1/2 wave long. |
Purplehaze
New member
Username: Purplehaze
Post Number: 1
Registered: 4-2004
| | Posted on Monday, April 26, 2004 - 1:09 am: |
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Well a 102.in steel whip as an all around ATENA. IS TUFF TO BEAT.. OTHER ANTEANS OFFER MORE MAGNIFICATION IE LOUDER.. BUT THE WHIP WILL BE MORE STEADY. IT WONT FADE IN AND OUT.. LIKE OTHERS MENTIONED...I DONT HAVE ELECTRONICS TRAINING.. BUT I HAVE 14..YRS OF EXPERIENCE!!!!! WITH MOBILES.. I AM JUST NOW GETTING INTO TO BASE UNITS.I THOUGHT THAT PEOPLE THAT TALKED ON BASES WHERE WEENIES...I HAVE TRIED 102IN WHIPS IN WILSONS ALSO IT STILL IS NOT AS STEADY AS THE WHIP ITSELF.. EVERYONE KNOWS IS A MOBILE WHEN YOU ARE ON THE MOVE YOU COME IN AND OUT MORE SEYA |
Bullet
Intermediate Member
Username: Bullet
Post Number: 323
Registered: 7-2003
| | Posted on Monday, April 26, 2004 - 6:40 pm: |
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no such animal!
they all at times come up on top...
depends on conditions..
thats why alot of guys use several antennas to switch from durring dx. |
Cm3885
Intermediate Member
Username: Cm3885
Post Number: 377
Registered: 12-2003
| | Posted on Tuesday, April 27, 2004 - 3:03 am: |
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People that talk on bases are weenies??????? Ummmmm o.....k.....
So what about us guys that own base setups but mostly talk in the mobile????? LOL
PS typing in all caps is considered SHOUTING on the internet and is looked by some as rude.. Just a note! :-) |
