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BOOTY MONSTER
05-30-2012, 07:08 PM
do you think they do more than just make the antenna work with a shorter over-all length ?
if you do , share your thoughts on what else they do ..... AND WHY ?

Gordon Gekko
05-30-2012, 07:18 PM
They might alter the angle of radiation and/or signal pattern. Just a speculation

BOOTY MONSTER
05-30-2012, 07:21 PM
care to speculate how they might do that ?

Mr.5150cbrn
05-30-2012, 07:42 PM
by forcing the signal up the radiating element

BOOTY MONSTER
05-30-2012, 08:22 PM
it is going up the radiator with or without a coil ...... if the signal wasn't making to the tip of the 108 it would be seen as short (on the cb band) and not want to tune .

but , what would keep the signal from traveling to the top of the full length element ?

coolbreeze
05-30-2012, 08:47 PM
back in the day the coil antenna was originally made so the big power guys could ride around and talk. On burbs or vans 102 drive around is not an option.
in the creation of many different coil antennas some have negative affect. to many coils or to tightly wound can result in a dummy load. also affect how they react with eachother in a 2 antenna set up.
why is one antenna design better then another. because of the inductance of the coil. or the capacitance created by the length of the bottom shaft. any by flat out testing, of which results coinsided with the mathmitical results.

BOOTY MONSTER
05-30-2012, 09:12 PM
so we agree , just for shortening ... and some are better designed and constructed than others ...
whodathunk ????

coolbreeze
05-31-2012, 07:51 PM
booty one thing we may not agree on is I think a coil is better then a 102 in any drive around situation. mainly for the layback factor while moving of the 102.

noisemaker
05-31-2012, 08:59 PM
I can tell you a coil antenna is a hellluva lot more broadbanded than a 102. If anyone cares to argue that, the analyzer is waiting.. ;)

BOOTY MONSTER
05-31-2012, 09:05 PM
i'll agree with both of those comments too . :300 (234):

coolbreeze
05-31-2012, 09:52 PM
booty are you feeling ok? seriously

BOOTY MONSTER
05-31-2012, 10:42 PM
i was thinking about asking you the same thing .

Mistah Gravy
07-01-2012, 02:24 PM
I can tell you a coil antenna is a hellluva lot more broadbanded than a 102. If anyone cares to argue that, the analyzer is waiting.. ;)

so,without any real technical background i ask this-you say that a coil antenna is a better all around out/in-put tx/rx than a tall whil like i've got on my Wilson 5000? i thought that the taller the whip,the better it would tx/rx? i do like the coil antennas but always thought and believed that the higher you are the better you get in and out,no?

Mr.5150cbrn
07-01-2012, 06:42 PM
not really , the higher placement of the antenna to a given vehicle is usually best , with regards to amount of available ground plane .
not nesisary the given length of the stinger
as in regards to the mfj anyliser " real technical background" can be curcumvented as the mfj does all the work

JesseJamesDallas
07-05-2012, 08:24 PM
I can tell you a coil antenna is a hellluva lot more broadbanded than a 102. If anyone cares to argue that, the analyzer is waiting.. ;)
Think your antenna analyzer needs some tweaking....

From the results cbradiomagazine found, the 102" Whip is the most broad banded...I will say i have never done a test like they did using a 102" whip and several different coiled antenna's, but I see no reason to dispute their findings since what they posted on the Predator 10K. is just what I see on mine.

http://cbradiomagazine.com/Feb%202007/CB%20Radio%20Antennas%20-%20Which%20one%20is%20right%20for%20you.htm

noisemaker
07-06-2012, 01:27 PM
Thats funny stuff. My 10k pretty much the same results, but i cant believe a 102 is that flat across the band.

I think im going to challenge that test and perform my own- on 2 different vehicles using the same meter.
I dont use lmr240, but i do run LMR400 in the little mobile, and 1/2" heliax in the burb. I even have a silverado too- i can test it on that as well so my tests can be as close as theirs.
Ill test all of the antennas, the bandwidth, the impedance, reactance, etc.
We'll do a 10k comp, a Terry Built 55R4, and a 102. (dont have a monkey)
THEN we will do a 102 by itself, then with a spring, and then with an extender tuned for 27.205.


Think your antenna analyzer needs some tweaking....

From the results cbradiomagazine found, the 102" Whip is the most broad banded...I will say i have never done a test like they did using a 102" whip and several different coiled antenna's, but I see no reason to dispute their findings since what they posted on the Predator 10K. is just what I see on mine.

http://cbradiomagazine.com/Feb%202007/CB%20Radio%20Antennas%20-%20Which%20one%20is%20right%20for%20you.htm

noisemaker
07-06-2012, 01:42 PM
Gravy- the wil5k is a base load. The coil antennas are more or less a center load. Though the theory is "go big or go home" isnt always the best. depends on vehicle, conditions, blah blah.. Elevation is definitely a key player.

Im going to perform a bunch of real tests with a bunch of different antennas, vehicles, and mounts -and see which one shines. Im also going to be adding a mini VNA to my arsenal of tools to see REAL TIME performance side by side (gain, take off angles, patterns, etc). Unlike others that make pretty spread sheets, ill take pics/video right from the source. AND I will make sure the skip isnt rolling when these tests are performed because testing/tuning while the D layer of the ionosphere is hot and opened is not optimal and will yield dud results.


so,without any real technical background i ask this-you say that a coil antenna is a better all around out/in-put tx/rx than a tall whil like i've got on my Wilson 5000? i thought that the taller the whip,the better it would tx/rx? i do like the coil antennas but always thought and believed that the higher you are the better you get in and out,no?

Bulldog-Unit777
07-28-2012, 07:02 AM
An antenna that is designed for so many fequencies and presents good SWR through that span is labeled: broadbanded, widebanded or ultrabanded. From what I understand in doing so the gain in these designs are a lot lower vs say a narrowbanded antenna just for 26.965-27.405 MHz. True or false? Plus some folks I believe are messing around with their mobile set up just for lower SWR, saying broadbanded but actually detuning, lowering gain but...SWR looks good, huh.

BOOTY MONSTER
07-28-2012, 08:20 AM
have you done any testing yet noise maker ?

Bulldog-Unit777
07-28-2012, 09:10 AM
Booty Monster, how does somebody come up with a gain factor on an antenna?

BOOTY MONSTER
07-28-2012, 09:33 AM
Booty Monster, how does somebody come up with a gain factor on an antenna?

depends on who that somebody is ..........
for similar designs , the larger the gain claim difference the more likely there are errors , location/terrain skewing as well as manipulation/lies are not uncommon either .....

heres what Sirio uses .

http://www.gain-master.it/technologies.php

"SIRIO has made comparisons with the best antenna on the market, with the aid of sophisticated equipment such as:
- Electromagnetic computer simulations carried out with *CST Studio Suite 2008 (http://www.gain-master.it/images/cstbig.jpg).

- Far-field signal analysis with portable Spectrum Analyzer FSL-6 *Rohde & Schwarz.

- S-parameters analysis in time and frequency domains with 8753ES (http://www.gain-master.it/images/networkan1big.jpg) Vector Network Analyzer and E5071B (http://www.gain-master.it/images/networkan2big.jpg) *Agilent Technologies.

- RF power tests with directional sensor NRT-Z14 (25MHz-1GHz) *Rohde & Schwarz.

- Coil thermal image with *TESTO 880-3 (http://www.gain-master.it/images/labview2big.jpg).

- Data collection from instrumentation and post-analysis with software developed by Sirio with LabView2009 (http://www.gain-master.it/images/labview1big.jpg)* National Instruments.

- Materials and components tested at extremes temperature with Vötsch climatic chamber VC4018 (http://www.gain-master.it/images/cameraclimaticabig.jpg) Vötsch Industrietechnik.

just a little bit more technical than walking around with a meter and relying on radio S-meters with who knows what effecting their antennas .

Mr.5150cbrn
07-28-2012, 10:11 AM
depends on who that somebody is ..........
for similar designs , the larger the gain claim difference the more likely there are errors , location/terrain skewing as well as manipulation/lies are not uncommon either .....

heres what Sirio uses .

http://www.gain-master.it/technologies.php

"SIRIO has made comparisons with the best antenna on the market, with the aid of sophisticated equipment such as:
- Electromagnetic computer simulations carried out with *CST Studio Suite 2008 (http://www.gain-master.it/images/cstbig.jpg).

- Far-field signal analysis with portable Spectrum Analyzer FSL-6 *Rohde & Schwarz.

- S-parameters analysis in time and frequency domains with 8753ES (http://www.gain-master.it/images/networkan1big.jpg) Vector Network Analyzer and E5071B (http://www.gain-master.it/images/networkan2big.jpg) *Agilent Technologies.

- RF power tests with directional sensor NRT-Z14 (25MHz-1GHz) *Rohde & Schwarz.

- Coil thermal image with *TESTO 880-3 (http://www.gain-master.it/images/labview2big.jpg).

- Data collection from instrumentation and post-analysis with software developed by Sirio with LabView2009 (http://www.gain-master.it/images/labview1big.jpg)* National Instruments.

- Materials and components tested at extremes temperature with Vötsch climatic chamber VC4018 (http://www.gain-master.it/images/cameraclimaticabig.jpg) Vötsch Industrietechnik.

just a little bit more technical than walking around with a meter and relying on radio S-meters with who knows what effecting their antennas .

also its the same snake oil used by sirio in their advertizing claims to fool the buffoons that copy and paste their theories .
as if they did utilize all of the above into every single antenna , there wouldnt be any other manufacturers in existence and everyone would own a sirio
and the home brewers would still be left out in the cold
as the "HOMEDEPOT" doesnt offer the test equipment that are described in the above post!


also i may add , the trusty old field streangth meter that has been around for nearly 70 years or so , that also the space programs , navy and other services have used with numerous great results !

Bulldog-Unit777
07-28-2012, 10:30 AM
also i may add , the trusty old field streangth meter that has been around for nearly 70 years or so...

Mr.5150 you hit the nail on the head! In the end no matter what is being said or done the field strength meter, when used correctly gives a pretty good picture.

BOOTY MONSTER
07-28-2012, 10:34 AM
the FSM doesn't commpensate for effects from the field (or the person holding it) ..... it's just another indicator .... but not definitive .

Bulldog-Unit777
07-28-2012, 10:38 AM
I would think if it could be on a tripod or by some other means that would not influence readings.

BOOTY MONSTER
07-28-2012, 10:58 AM
how far do you think you have to be away from it to not cause any effects from your body ? and the tripod doesn't account for surrounding effects . and i know you're bright enough to not use a metal tripod BD .

it's simply a indicator , like a check engine light . it tells you something is going on ...... but it doesn't tell you how or why . better than nothing though "when used correctly " as you said BD

coolbreeze
07-28-2012, 12:25 PM
An antenna that is designed for so many fequencies and presents good SWR through that span is labeled: broadbanded, widebanded or ultrabanded. From what I understand in doing so the gain in these designs are a lot lower vs say a narrowbanded antenna just for 26.965-27.405 MHz. True or false? Plus some folks I believe are messing around with their mobile set up just for lower SWR, saying broadbanded but actually detuning, lowering gain but...SWR looks good, huh.

correct!!!

with 2 antennas, 2 hot or bounceback the fools who tune for minimal swr are loosing gain

coolbreeze
07-28-2012, 12:32 PM
the best way to use a field strength meter is to have it sitting on a non conductive material say 100ft in front of a mobile. for a base you would have to go much further away.

you can also use micro amp meter and hook it to your s meter leads in a radio. you can see changes in signal in small amounts that a meter in the face wont show you. digital is obviously the better choice.



also when companys post gains of their antennas, its at the standard they developed or use. There is no industry standard so all is tested equally. So any manufactures specifications are about as useless as booty says using a s meter on someones radio 30 miles away is.

Bulldog-Unit777
07-28-2012, 03:52 PM
OK Coolbreeze I have been guilty of using my Cobra 2000 at the receive station, using a video camera, and go out in the mobile to a fixed spot. Do an antenna swap and make my own choices what antenna to run. I know that is not the best method and admit to that but so far based on experience of usage it has been a good indicator for me. In the end it is all about being heard. It is unfortunate that, not all radios have poor receive thus taking more power to make a trip. Sometimes your lower powered radios have better receive than higher powered radios. Most folks of knowledge will lean towards low powered radio with amp makes a good set up. Some folks say getting out is actually harder these days than in the past. Every now and I like to brush up on this topic of mobile antenna, thanks.

BOOTY MONSTER
07-29-2012, 12:53 PM
nothing wrong with using what you got to get the best results you can . but insisting that everyone everywhere will have the same results is miss-leading .

JesseJamesDallas
07-29-2012, 04:54 PM
I use a tone generator App I downloaded on my Smartphone, and a 4' florescent light bulb...

Duck tape the Mic's PTT button down, then set the tone generator...Then I stick the light bulb up to the antenna to make it light-up, and start walking around the truck and where ever the bulb go's out, I place a Playing Card on the ground...

Then re-adjust the antenna, and do it all over again!.......Trick is holding the light bulb at the same height while walking...

noisemaker
07-29-2012, 08:47 PM
I do the same damn thing jjd! I got the light bulb 80 FEET infront of the truck before it goes out, 2feet in the back of the truck. Thats with the flat coils. Im making a set of fighting stix for one of my homeboys in the minigrass and ill be testing that the same way. Hope i get same results

SkipShooter
08-30-2012, 11:27 PM
Thats funny stuff. My 10k pretty much the same results, but i cant believe a 102 is that flat across the band.

I think im going to challenge that test and perform my own- on 2 different vehicles using the same meter.
I dont use lmr240, but i do run LMR400 in the little mobile, and 1/2" heliax in the burb. I even have a silverado too- i can test it on that as well so my tests can be as close as theirs.
Ill test all of the antennas, the bandwidth, the impedance, reactance, etc.
We'll do a 10k comp, a Terry Built 55R4, and a 102. (dont have a monkey)
THEN we will do a 102 by itself, then with a spring, and then with an extender tuned for 27.205.

OMG dont EVER use spring on any antenna... thats a good way to blow your stuff up

doughboy
09-01-2012, 03:38 PM
the real stainless spring that the police used to use are great but very hard to find now a days