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Bullseye
Intermediate Member
Username: Bullseye

Post Number: 302
Registered: 1-2002
Posted on Monday, April 09, 2007 - 9:59 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I am going to be running a Anttron A-1700 for practical purposes. When I want to do some serious DX'ing or a CEF net will I gain anything switching to a 102" SS whip for that or would it be more effort than gain?
Bullseye/CEF#110/Mem. Since 1/18/2002
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Penrider
Member
Username: Penrider

Post Number: 70
Registered: 1-2007


Posted on Tuesday, April 10, 2007 - 12:08 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

antenna Length (102" whip) matters as much if not more than gain (center or base loaded antenna), Especially for dx....if you mount that 102" as high as possible, as close to the center of your vehicle as possible, good clean grounding of antenna mount, good clean coax and connections it will blow the socks off that Anttron...plus the above conditions will give you as close to perfect SWR as it gets, that's the beauty of a 102"
Sean
CEF867
CVC81

"Keep smiling, it makes people wonder what you're up to!!"
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Wolverine
Advanced Member
Username: Wolverine

Post Number: 665
Registered: 2-2003
Posted on Tuesday, April 10, 2007 - 2:49 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

The taller the antenna the better, 102" whip would be great if you don't have any height restrictions and if you're going to be transmitting while standing still..... the problem is if you're going to xmit while the mobile is moving, your swr will fluctuate greatly due to the 102" whip bending backwards. For practical purposes, stay with the anttron.
Wolverine.
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Bullseye
Intermediate Member
Username: Bullseye

Post Number: 303
Registered: 1-2002
Posted on Tuesday, April 10, 2007 - 6:34 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Thanks Guys and the plan I'm working on here is that the 102" will be used sitting still probabaly down by the lake to try to hit available skip or the CEF nets till I get my base up and running.
Bullseye/CEF#110/Mem. Since 1/18/2002
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Jameslarson
Intermediate Member
Username: Jameslarson

Post Number: 306
Registered: 4-2006


Posted on Tuesday, April 10, 2007 - 10:17 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

The 102" would be great. However, where to find one nowadays. Radio Shack is sold out and well, I'm sure if yulooked hard enough they could be found. I for one like the Predator 10K. Smaller in length, and actually better performance. Go figure. Good Luck.
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Tech237
Moderator
Username: Tech237

Post Number: 742
Registered: 4-2004
Posted on Tuesday, April 10, 2007 - 12:12 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

James,
Both Tech833 and I have said this many times before - a loaded or shortened antenna can never be as good as a fullsize antenna all things being equal. If/when you have a shortened antenna out performing a fullsized one, it is time to start looking for reasons why.

Were both tried using the same base and mounting location, were the conditions the same for both tests? Was the fullsized antenna clear of nearby obstructions?

If you start closely looking, you will find a reason why and it will most probably have nothing to do with the antennas themselves.

Simon
Tech237
KD7IEB

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Bullseye
Intermediate Member
Username: Bullseye

Post Number: 304
Registered: 1-2002
Posted on Tuesday, April 10, 2007 - 4:02 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I have'nt tried either yet as they are still in transit. I'm just wondering if I would or should notice a difference in my TX & RX signal. They will both be mounted to the same mount,coax amp,meter,and radio system. I was simply wondering if the 102" would help for specialized situations,such as the CEF nets or trying to catch some skip, as it is too long for me to leave on for everyday use so I would be switching them out if the SWR's and such were acceptable.
Bullseye/CEF#110/Mem. Since 1/18/2002
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Kid_vicious
Senior Member
Username: Kid_vicious

Post Number: 2479
Registered: 9-2004


Posted on Tuesday, April 10, 2007 - 4:41 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

yep, sorry james, the ads are lying.

a 102" whip mounted to the center of the top of a van, done the right way, is the absolute best mobile antenna setup you can hope for.

they call it antenna theory, but its not because they are guessing.

manufacturers build what people will buy, and sadly, many people believe these antennas to be the greatest thing since sliced bread.
coils create loss, period

you already have the best mobile setup around as far as antennas go. ive seen the pics!LOL
if you make sure that every panel on that van is connected electrically to every other panel on that van, and to the frame, you have the best you can get.
remember, that we are at the bottom of the sunspot cycle, and nothing you do at this point is going to bring any DX into your radio.

wait a year and watch your 102" whip kick serious butt!

hey bullseye,

yes, you will do a bit better trying for DX sitting still at the lake with the 102" whip, but the difference is probably not the difference betwen hearing DX stations and not hearing them. (see above)
when the skip is in, you will hear it on your anttron, and be able to talk to them.

now, if you want to take a big step up in DXing ability, get an antron 99, a 5 foot mast, and a stake to pound in the ground to hold the mast up.

pound the stake in on the shore where the water is less than a foot deep, and put the mast on the stake, mount the antron to the mast, making sure there is a good electrical connection from the antenna mounting brackets to the mast.

now you are using the entire lake as your groundplane!!!

if you cant make this work, some sort of mount that you can drive your tire over, and put a mast up on will work great.
got a friend who's a welder?
there ya go!

seriously, with the ease of putting together an antron99, and its portability, its hard to beat for camping trips.
best of luck,
matt
anyone wanting a "clean signal", just look to the left and build one of these!!!
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Jameslarson
Intermediate Member
Username: Jameslarson

Post Number: 310
Registered: 4-2006


Posted on Tuesday, April 10, 2007 - 4:53 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Hi Tech237. Yes, I know that in theory a loaded antenna should not out perform a 102". However, for whatever reasons, I receive better and transmit better with the Predator 10K versus a 102" whip. Just like many other Predator users here.

Yes, both conditions were exactly the same. Both were clear of any obstructions. Same mounting location. Same coax, mount, etc.. Same SWR (Literally flat). Same mount. Same everything. Even compared the two back to back it in different locations, different times of day, different radios, etc.... When both were tested back to back against each other in exactly the same scenarios, the Predator 10K outperformed.

Again, I (as well as others here) know that the loaded antenna 'should' NOT have been better, but that was not the case as others that use the 10K here can attest to as well. I dont know. I guess it's just one of those things you know.
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Kid_vicious
Senior Member
Username: Kid_vicious

Post Number: 2480
Registered: 9-2004


Posted on Wednesday, April 11, 2007 - 1:00 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

go figure,

i cant refute your real world findings about the two antennas.

i agree, maybe its just one of those things.LOL

what i can say is that the difference between the two should not have been much at all.
i mean hard to notice while testing.

if you were transmitting to the same station with each antenna from the same location with the same wattage out, the station receiving should not have been able to tell the difference on their meter AT ALL!

think about it, a radio's S-meter is generally calibrated at 6db, meaning that each 6db increase will yeild a 1 S-unit increase.

since both of those antennas have 0 gain, the difference should not have been noticable.

i GUARANTEE you that neither of those antennas have a 6db or even a 3db advantage over the other.

who knows,
matt
anyone wanting a "clean signal", just look to the left and build one of these!!!
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Mrgoody
Junior Member
Username: Mrgoody

Post Number: 39
Registered: 1-2005
Posted on Thursday, April 19, 2007 - 8:27 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Hello every one:I would like to know if anyone have ever heard of a (black widow)antenna. I wanna hook one up to my mobile.Now I will be mounting it to a diamond super gain k400 trunk lip (stud) mount...how would I ground it and also,their is a hole maybe about 2" from the bottom of the shaft...? what is that hole there for.
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Road_warrior
Senior Member
Username: Road_warrior

Post Number: 2093
Registered: 7-2004


Posted on Friday, April 20, 2007 - 8:32 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Jameslarson, what's your secret on getting a 102"
tuned with a flat Swr reading.
I've never got one down past 1:3:1

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