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BOOTY MONSTER
12-09-2011, 12:20 PM
here's a link to the full thread about my attempt at building the antenna . the first several pages are basically me finding out my initial ideas for it were not up to snuff . eventually i got what i wanted ....

http://www.worldwidedx.com/home-brew/102961-booty-4-a.html

http://i867.photobucket.com/albums/ab234/BOOTY-MONSTER/IMG_0140.jpg

http://i867.photobucket.com/albums/ab234/BOOTY-MONSTER/IMG_0160-1.jpg

http://i867.photobucket.com/albums/ab234/BOOTY-MONSTER/IMG_0163.jpg

http://i867.photobucket.com/albums/ab234/BOOTY-MONSTER/IMG_0162.jpg

Lunchbox
12-09-2011, 01:24 PM
Booty,
Do you have any sort of instructions for us antenna noobs out here? And how much power does that handle?

BOOTY MONSTER
12-09-2011, 02:01 PM
i guess the best instruction i could give is to not be afraid to try . i just copy time proven designs , i'm not trying to reinvent the wheel . keep it simple for your first antenna , like a dipole or 1/4 wave ground plane . when it works you'll have a lot more confidence to try something bigger .

i have no idea how much power it will handle , i only run 200 pep . i built it really strong physically to be sure it can survive the hurricanes we get here on occasion . i guess the weak point power wise would be the mobile stud mount or the tape used for the insulator in the gamma . it would be very simple to direct feed it from the coax to eliminate the stud . and a teflon tube can be had for it for 10-15 bucks , if i recall correctly . or a better/stronger gamma could be added . i'm sure the rest of it could handle several thousand watts or more easily .

Mistah Gravy
04-11-2012, 07:54 PM
what determines how much wattage an antenna will handle(please explain it as if you are talking to a six year old with no technical background)thank you...Gravy626

BOOTY MONSTER
04-11-2012, 08:18 PM
i've noticed antennas with very high power ratings typically have heavier gauge and larger diameter elements along with teflon or delron insulators , slit tubing with hose clamps seems favored over swagged ends with screws FWICT to . it has to be assembled correctly too ;)

hopefully others will reply to your question with a better answer .

scooter71nc
03-27-2013, 12:21 PM
Well in the past I have found that most base antenna are able to hold more power than they are rated with some small mods. It all depends on if it is a fiberglass or a alum. antenna. the antennas such as antron 99 and the imax 2000 are pretty much what they are but other that are alum. can hold more. Some alum antenna's such as the maco V58 and simlar are controlled by a coax connector and a wire. you can change the wire size and go to better connector for more wattage handling or even just hot feed it and bypass the coax connector and wire for a very high wattage rating. other antenna are controlled by a gamma such as the antenna talked about in the post or even a beam antenna. On this case just buy a larger gamma or make your own with teflon or delron. The main thing to know is other than the gamma or such thing the coax and coax connectors are your weakest link. so I sugguest hot feeding if you are running anything above 7.5Kw bird Rms. hope this helped

High Voltage Mobile NJ
03-27-2013, 03:21 PM
Booty Monster I love that Antenna to death. But Rule Of Thumb says you are not suppose to make wraps like that with your coax being the feedline transmission. it will eliminate noise yessssss . but you will loose velocity as well as gain factor and forward gain . this has been proving when some of the big boys do that on there beams and they make silly wraps like that . you get a weak spot or a hot spot in time when you run power through it , and in time the coax will fail at the wraps cause the energy will be so compressed and focused like running current through a small piece of 16 gauge wire. your performance would be much superior with an AIR VARIABLE CAPACITOR with a voltage rating of 5000 volts or higher . 3-200 pica farads is nice . sometimes you have to go lower, it will depend on your wavelength. :300 (185):

BOOTY MONSTER
03-28-2013, 01:02 PM
thanks for the compliment :)

" ...... but you will loose velocity as well as gain factor and forward gain . this has been proving when some of the big boys do that on there beams and they make silly wraps like that . ...... "

if by bigboys you mean folks on the super bowl ................ spare me .......................................

i've never noticed or read any of the negative comments about coax chokes that you mentioned . can you elaborate on the how/why of that happening ?

High Voltage Mobile NJ
03-28-2013, 03:27 PM
thanks for the compliment :)

" ...... but you will loose velocity as well as gain factor and forward gain . this has been proving when some of the big boys do that on there beams and they make silly wraps like that . ...... "

if by bigboys you mean folks on the super bowl ................ spare me .......................................

i've never noticed or read any of the negative comments about coax chokes that you mentioned . can you elaborate on the how/why of that happening ? if you cant read and search what I have wrote before , you have a problem reading . go look it up or talk to a real hard core cber like myself.

BOOTY MONSTER
03-28-2013, 04:20 PM
LOL !!!!!!!!!!

thanks for making a claim and then not backing it up ....................

High Voltage Mobile NJ
03-29-2013, 03:40 AM
lol !!!!!!!!!!

Thanks for making a claim and then not backing it up ....................i did back it up . Your just in a class all by yourself and your a very ignorant person. Your a legend in your own mine. Anybody just getting into cb radio can understand what i wrote , but you , lol lol lol pack ya bags mudduck . You cant take it when someone is right and has more knowledge and brains that you. Now thank high voltage mobile nj for that maul i just gave you . :300 (177)::300 (185)::300 (97):

CBRN38
03-31-2013, 08:46 PM
HV just remember if booty didnt read it, it cant be true. if booty didnt read it, he wont know anything else.
WHY you ask, because he doesnt do any testing nd field trial and error for himself. He cant, to fat and they dont make a step ladder that can hold him, concrete blocks can only be stacked so hi without being unstable

High Voltage Mobile NJ
03-31-2013, 09:30 PM
hahahahahahaha:angel:

BOOTY MONSTER
04-01-2013, 03:05 PM
i did back it up . Your just in a class all by yourself and your a very ignorant person. Your a legend in your own mine. Anybody just getting into cb radio can understand what i wrote , but you , lol lol lol pack ya bags mudduck . You cant take it when someone is right and has more knowledge and brains that you. Now thank high voltage mobile nj for that maul i just gave you . :300 (177)::300 (185)::300 (97):

no need to flame just because you're put on the spot by not having any evidence to back up a bull chit claim .

BOOTY MONSTER
04-01-2013, 03:07 PM
HV just remember if booty didnt read it, it cant be true. if booty didnt read it, he wont know anything else.
WHY you ask, because he doesnt do any testing nd field trial and error for himself. He cant, to fat and they dont make a step ladder that can hold him, concrete blocks can only be stacked so hi without being unstable

if it were possible to stack concrete block as high as the piles of crap you spew .... i could touch the moon .

High Voltage Mobile NJ
04-01-2013, 04:19 PM
no need to flame just because you're put on the spot by not having any evidence to back up a bull chit claim . learn how to read booty> its life.

Moonchild 747
05-08-2013, 07:42 PM
New here and just wanting to shed a little light to the whole "balun" thing for others who might not quite understand why a balun is used...I am no expert nor did I stay at a Holiday Inn last night but I have been studying matching networks for a good bit now and would like to help anyone following what happens when using a balanced antenna and feeding it with an unbalanced transmission line...Hence BAL/UN...I'll try to keep this simple and short...haha...
The transmission line choke balun is not any sort of transformer. A transformer transforms, which is where energy is lost as converted heat. The common mode air choke works fine as a balun but isn't a transformer, so no loss due to converted heat. Now how the coax works...The inner conductor of the coax only has a magnetic effect on the inner surface of the shield and vice versa. The current on the inner conductor MUST be exactly equal and opposite the current on the inner surface of the shield. Any differences in current from the inner conductor to the braid MUST manifest itself in currents on the outer surface of the braid (Common Mode Currents). By winding the coax into a coil these differeneces are eliminated (or at least greatly reduced) by a choking action thus balancing the signal on one end of the device regardless of what is happening on the other. Only the outer surface of the braid has any effect, which is where the common mode currents ride on back to the shack. The inner surface of the braid and the inner conductor simply behave as a longer piece of coax, nothing more, only effect would be line loss in dB due to the type and length of the coax at that specific frequency. They have absolutely no magnetic effect on the outside world and only the same effect on each other as they normally would in a straight piece of coax. The effect is to choke currents on the outer surface and to match any mismatch in impedance between the antenna and the radio...This is why you'll see people put these coils at the feed points of their antennas...But this method has really only been commonly used since the early 80's so why didn't radio enthusiasts need these coils before? Cause radio shacks back then weren't littered with electronics and hifi equipment susceptible to EMI...See not too long...Thanks for the topic...

High Voltage Mobile NJ
05-09-2013, 12:09 AM
New here and just wanting to shed a little light to the whole "balun" thing for others who might not quite understand why a balun is used...I am no expert nor did I stay at a Holiday Inn last night but I have been studying matching networks for a good bit now and would like to help anyone following what happens when using a balanced antenna and feeding it with an unbalanced transmission line...Hence BAL/UN...I'll try to keep this simple and short...haha...
The transmission line choke balun is not any sort of transformer. A transformer transforms, which is where energy is lost as converted heat. The common mode air choke works fine as a balun but isn't a transformer, so no loss due to converted heat. Now how the coax works...The inner conductor of the coax only has a magnetic effect on the inner surface of the shield and vice versa. The current on the inner conductor MUST be exactly equal and opposite the current on the inner surface of the shield. Any differences in current from the inner conductor to the braid MUST manifest itself in currents on the outer surface of the braid (Common Mode Currents). By winding the coax into a coil these differeneces are eliminated (or at least greatly reduced) by a choking action thus balancing the signal on one end of the device regardless of what is happening on the other. Only the outer surface of the braid has any effect, which is where the common mode currents ride on back to the shack. The inner surface of the braid and the inner conductor simply behave as a longer piece of coax, nothing more, only effect would be line loss in dB due to the type and length of the coax at that specific frequency. They have absolutely no magnetic effect on the outside world and only the same effect on each other as they normally would in a straight piece of coax. The effect is to choke currents on the outer surface and to match any mismatch in impedance between the antenna and the radio...This is why you'll see people put these coils at the feed points of their antennas...But this method has really only been commonly used since the early 80's so why didn't radio enthusiasts need these coils before? Cause radio shacks back then weren't littered with electronics and hifi equipment susceptible to EMI...See not too long...Thanks for the topic...your forgetting about eddy currents and if you run to much power in time the coax will fail being wrapped like that . your totally missing what I said and that is a fact . :boink:

BOOTY MONSTER
05-09-2013, 12:53 PM
moonchild , thanks for providing further evidence that "you can't fix stupid"

High Voltage Mobile NJ
05-09-2013, 12:58 PM
moonchild , thanks for providing further evidence that "you can't fix stupid"pack ya bags mudduck . until you no how to get your name called repeatly and have confidence of ya station and have absortion to your brain when real technical people are trying to teach you a lesson . shhhhhhhhhhhhhhhh pack ya bags . :bathbaby::kiss:

BOOTY MONSTER
05-09-2013, 01:07 PM
pack ya bags mudduck . until you no how to get your name called repeatly and have confidence of ya station and have absortion to your brain when real technical people are trying to teach you a lesson . shhhhhhhhhhhhhhhh pack ya bags . :bathbaby::kiss:

once again .... nothing but flames to back up bullshit .
but you're just a cbrn wannabee nuthugger ....... so your babble is expected .

Moonchild 747
05-09-2013, 07:49 PM
your forgetting about eddy currents and if you run to much power in time the coax will fail being wrapped like that . your totally missing what I said and that is a fact . :boink:

Actually I got your point and I wasn't meaning to prove anyone wrong with my post, I was just adding information concerning baluns to those reading and possibly trying to show a little about why people wrap coils of coax under their antennas...I obviously left out a lot more information but stated earlier I wouldn't go into great detail on the subject...Not everyone uses a balun or air choke and yes if you coil your coax in such a fasion that the beginning and ending leads of the coil are close you will end up frying some coax using moderate to high power, but if you evenly space your turns out so that the beginning and ending coax leads don't get put together like they would if you was rolling up an extension cord then you should be fine up to several hundred watts...So I didn't mean to ignite a feud between you and Mr Monster...I don't know either one of you so I'll keep my opinions to myself until the time come for me to let them out...Thank you

High Voltage Mobile NJ
05-09-2013, 09:26 PM
Actually I got your point and I wasn't meaning to prove anyone wrong with my post, I was just adding information concerning baluns to those reading and possibly trying to show a little about why people wrap coils of coax under their antennas...I obviously left out a lot more information but stated earlier I wouldn't go into great detail on the subject...Not everyone uses a balun or air choke and yes if you coil your coax in such a fasion that the beginning and ending leads of the coil are close you will end up frying some coax using moderate to high power, but if you evenly space your turns out so that the beginning and ending coax leads don't get put together like they would if you was rolling up an extension cord then you should be fine up to several hundred watts...So I didn't mean to ignite a feud between you and Mr Monster...I don't know either one of you so I'll keep my opinions to myself until the time come for me to let them out...Thank you naghhhhh naghhhhhh naghhhhhhh your fine. but I like to explain in direct detail right away in about one to 2 sentences . I don't need a paragraph to get my point across. lol lol lol :kiss:

Moonchild 747
05-09-2013, 10:44 PM
naghhhhh naghhhhhh naghhhhhhh your fine. but I like to explain in direct detail right away in about one to 2 sentences . I don't need a paragraph to get my point across. lol lol lol :kiss:

Gotcha...see your point...

High Voltage Mobile NJ
05-10-2013, 08:51 AM
BUMP BUMP.:graffiti:

JAFO
08-17-2015, 02:41 PM
BUMP BUMP.:graffiti:
Yeah, a little old but still an interesting thread, just thought I'd add that you are ALL fairly correct.

I prefer not to call a 'Common-Mode-Current Choke' (cmcc) a "balun", but balun DOES mean "balanced to unbalanced", usually attributed to a coax fed dipole, where both sides of the wire or tubing making a dipole are of equal length - therefore 'Balanced'.

When you go from coax (unbalanced) into the match of an antenna, a cmcc is also a good idea, as long as it's at or very near a current node.

The reason a cmcc tends to heat up is because there's a mismatch at the antenna, often at the 2nd or 3rd harmonic which poorly aligned radios, (increasing of course when amplified, especially those with spread harmonic filter coils!) tend to create at much higher levels than they should,
- plus the coax often happens to be cut to a resonant length for one or more harmonics so it ends up being a 'friendly load' for the harmonics on the coax casing, and all that 2nd or 3rd harmonic wattage is being only partially stopped by the correctly wrapped for the fundamental freq choke, then heading up to an antenna, usually with a DC ground shunt tuned for only the fundamental frequency which acts like a DC short to harmonics, causing heating & molten DEATH to feedline.

Keep the radio clean & aligned and your amplifier won't be bogged down trying to also amplify 54MHz, 81MHz, 108MHz etc., causing high SWR and heat.

At least that's what some CBr told me http://www.cbjunkies.com/images/icons/icon6.png