broomstick vs whip

Submitted: Wednesday, Feb 25, 2004 at 15:02
ThreadID: 10783 Views:3231 Replies:10 FollowUps:15
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todays uhf question, which you are all no doubt getting sick of:

what are the advantages of a broomstick antenna, say 6 db, compared to a whip? is the signal any better? i know the bulk of signal comes from the base of the whip, does a broomstick transmit from higher up?

i presume whips are more likely to break from fatigue (not including contact with, err, foreign objects)

cheers, tim c
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Reply By: The Banjo - Wednesday, Feb 25, 2004 at 15:26

Wednesday, Feb 25, 2004 at 15:26
Far as I know broomstick v whip may not be the right question - antennas are designed to suit the wavelength and system in use etc......I think broomsticks are commonly CDMA phone.......whips are usually HF.......UHF models built by the pro's such as GME Electrophone all seem modular with the phasing coils mid wire and the grounding bits at the base. For mine, to choose a pro model to suit the conditions intended is the way. 6 db for mobile in flat country, 9db for static use and a shorty for undulating country (sand hills) - modulars allow you to make changes as you go..............whatever.....this approach has worked for me.I need red sand under me.
AnswerID: 48048

Follow Up By: Wayne (NSW) - Wednesday, Feb 25, 2004 at 18:34

Wednesday, Feb 25, 2004 at 18:34
Bromsticks can be both. you can get broomstick CDMA and broomstick UHF . I have been running a whip for years, replaced it once after someone wanted it more than me.I have now gone to a broomstick. When iI am around town or driving in the mountians where trees can be a problem, I fit the broomstick to the bullbar. When I go to the desert I mount the broomstick to the roof rack. Up there I can easy get 10 -15 kl range.

When the broomstick is mounted on the bull bar the hight of it is just higher than the vehicle so I can tell if I am going to hit anything at roof height

WayneAlways Out'N About
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Follow Up By: The Banjo - Wednesday, Feb 25, 2004 at 21:12

Wednesday, Feb 25, 2004 at 21:12
Understood Wayne.....will keep an eye out for them ....who did you get the BS UHF from ?I need red sand under me.
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Reply By: Martyn (WA) - Wednesday, Feb 25, 2004 at 15:30

Wednesday, Feb 25, 2004 at 15:30
tdcockers,
I've got both and I interchange them depending on what I'm doing, I do find the broomstick antenna margianlly better all round when on a long trip on long stretches of open country, apart from that I couldn't honestly say I notice a huge difference, I though it was to do with the amount of antenna you have above the roof line of the vehicle and the distance between other antennas that made more of a difference, I have one antenna on the back (HF) and one on the bullbar (UHF) and everything works fine (ish). Keep the shiny side up
AnswerID: 48050

Follow Up By: jeff-wa - Wednesday, Feb 25, 2004 at 17:01

Wednesday, Feb 25, 2004 at 17:01
With UHF it would be better to get the BASE above the roof line, of course not very practical around town (won't go in the dam garage!) :-) Also not as sturdy as on the bullbar and has nowhere near the same image! :-)
Gotta love the bullbar mount!
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Follow Up By: tdcockers - Wednesday, Feb 25, 2004 at 17:15

Wednesday, Feb 25, 2004 at 17:15
i actually don't have a bullbar :(

infact, i don't have a 4wd :'(

i am sort of planning - short to medium term, to get a DIN mount uhf (tx4400 if the budget will stretch, otherwise a UH088) to put underneath my stereo in the dash with a benelec 3/6.5db elevated feed antenna mounted on the bonnet passenger side, and a car kit for my nokia 3315 (a bloke is selling them brand new for $130 on ebay) with a 9db broomstick on the opposite corner of the bonnet as an external antenna.

admittedly, it has a lot to do with image, but i also figure if they are treated nicely then the whole lot, including my stereo can just be carried into the next few cars i have. i am aiming for good performance, being a road car, the whips main stress will be just wind at highway speeds.

any feedback? problems? (you can stop laughing now)
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Reply By: jeff-wa - Wednesday, Feb 25, 2004 at 17:25

Wednesday, Feb 25, 2004 at 17:25
Lot's of people run UHF in road cars, nothing to be embarresed about. If you are just going to be around town there is an absolute ripper arial from GME. It's a 2.5db Dipole that you can mount to the gutters (for extra height) it's only about 30-40cm long total length. It's ground independant and $27 Retail inc GST from any 4wd shop or CB store. You'll find around the city the lower the dB the better off you are (if you are trying to access repeaters). Repeaters are normally placed as high as they can get them with very high dB arials. This means they can go the distance however unless your signal can go up in the air to the same kind of height that they are transmitting from you will not get good coverage.
Think of UHF as a bit of play-dough. You start off with a sphere or ball and the higher your dB the longer your signal gets but it get's narrow and more directional. ie If you go behind a building or in a dip you get nothing. The idea is to try and get your signal and the signal of the repeater or the person you are talking to, to overlap. Seeings as the guys setting the repeater up have already spend $$$ on high gain arials and prime positions to transmit from, all you have to do is get an arial that will reach up high enough to overlap theirs (a low db arial).
PHEW! I hope all that made sense?!?!
Basically you will very rarley be high enough while driving your car to make good use of a high gain arial while in the city. (especially Perth as it is very hilly).
AnswerID: 48059

Follow Up By: tdcockers - Wednesday, Feb 25, 2004 at 17:28

Wednesday, Feb 25, 2004 at 17:28
understood. very clear.

i had one of those antennas, but sold it after my last system (remember that?) got cooked. the only real probem with roof mount, it that the camry doesn't have gutters. well it does, but its just a mould on the body, not an added on bit.
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Follow Up By: tdcockers - Wednesday, Feb 25, 2004 at 17:29

Wednesday, Feb 25, 2004 at 17:29
what exactly does dipole mean, btw?
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Reply By: jeff-wa - Wednesday, Feb 25, 2004 at 17:33

Wednesday, Feb 25, 2004 at 17:33
A Dipole is just a different way of transmitting/receiving. Basically from my limited understanding you split the antenna in half I think UHF wavelength is approx 70cm so instead of having a half wave or quater wave antenna etc you can have a full wave but with only half the size. (there is a lot more to it than that, but someone will have to help me on that). I remeber my dad and I building a dipole out of a film cannister and 10m of Coax for my 27mhz CB when I was younger. To bit's of 5m coax joined and then fed back to the rig.
I have that little GME on a bonnet mount on my Surf and it works better than my 6db Whip and 4.5db Aliminium Dipole I had on my old 4by. Same radio too, just a ol' GME TX3000. Works fantastic though.
AnswerID: 48061

Follow Up By: tdcockers - Wednesday, Feb 25, 2004 at 17:42

Wednesday, Feb 25, 2004 at 17:42
i have just done a bit of research on repeaters where i live (sunshine coast, qld) we seem to be a bit light on for repeaters. one at maleny (about 30km straight line, i guess) one on the coast (maybe 15km) and one at imbil (60km? somewhere off to whoop whoop, anyway) what other than the range that the maleny tower is on, it is fairly flat. how far can the shorty reach? would a 3db elevated feed be similar?

if it is as good as you say, its an awesome investment. the shop i bought it from did say to me "you can buy this big one for $120, or you can get this little one that does the same job for $22"
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FollowupID: 309964

Reply By: jeff-wa - Wednesday, Feb 25, 2004 at 18:02

Wednesday, Feb 25, 2004 at 18:02
It depends on how good the repeater is. If you have clear line of sight I imagne you'd be ok. I can only just hit my "home" repeater from work in the car but it is 27kms as the crow flies and about 50m lower!! If you are the same height you will probally be ok.
AnswerID: 48066

Follow Up By: jeff-wa - Wednesday, Feb 25, 2004 at 18:03

Wednesday, Feb 25, 2004 at 18:03
Oh yeah, the 3db elvated would prob be better. Esepcially if you cannot mount to gutters and have to resort to the bonnet.
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FollowupID: 309969

Follow Up By: jeff-wa - Wednesday, Feb 25, 2004 at 18:03

Wednesday, Feb 25, 2004 at 18:03
Oh yeah, the 3db elvated would prob be better. Esepcially if you cannot mount to gutters and have to resort to the bonnet.
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FollowupID: 309970

Follow Up By: tdcockers - Wednesday, Feb 25, 2004 at 18:04

Wednesday, Feb 25, 2004 at 18:04
sounds good. the maleny one is about 90m higher, the coast one would be about flat from home, i think :)

thanks mate
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Reply By: Truckster (Vic) - Wednesday, Feb 25, 2004 at 20:03

Wednesday, Feb 25, 2004 at 20:03
One thing with a solid ariel, they break the bases if you drive under trees, carports, or carparks.. Ive done 2.. mate did his white fiberglass one last night in our carport, it was only a week old :(
AnswerID: 48079

Follow Up By: Member - Moggs - Wednesday, Feb 25, 2004 at 21:25

Wednesday, Feb 25, 2004 at 21:25
Truckster, did they have a spring base??? I have a GME 4702 solid fiberglass aerial on a spring base that I have wacked around for years - bends almost horizontal.Moggs ( Normanhurst NSW)
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Follow Up By: Truckster (Vic) - Wednesday, Feb 25, 2004 at 21:41

Wednesday, Feb 25, 2004 at 21:41
solid, NFI on the base... will check when I get my new 25w GME fitted :D
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FollowupID: 310026

Follow Up By: Member - Toonfish - Thursday, Feb 26, 2004 at 00:24

Thursday, Feb 26, 2004 at 00:24
hmmm 25 watts?
i like
got in trouble a few years back for doing that to my 27mhz for better sideband and interfered with a radio inspector over the road .
lol now .
no licence to lose eitherdont ask me how i found him.
oops sprung!!
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FollowupID: 310050

Reply By: Mad Dog Morgan (Geelong) - Wednesday, Feb 25, 2004 at 22:27

Wednesday, Feb 25, 2004 at 22:27
Don't be too concerned, just get a big flexible mother so you have plently of signal capture. You'll only notice the 3db difference when operating at the extreme limit of distance. It doesn't matter if you open the repeater at strength 5 or 6 you'll be heard just the same. BEAM ME UP SCOTTY


Hooroo
Ray
AnswerID: 48113

Reply By: Roachie - Wednesday, Feb 25, 2004 at 23:31

Wednesday, Feb 25, 2004 at 23:31
I've got both a 5 foot long broomstick and a shorter ground-plane-independant whip antennas side by side on my bullbar. They are connected to a DickSmith 3-way switch. I honestly cannot notice any difference between the 2 of them under most circumstances. I "think" the broom stick gets better range in flat open country. In reality however, it's difficult to say for sure....let's face it, you're normally only going to be talking to somebody else in your own convoy/group, which usually won't be spread out more than 5 klicks or so. Any further than that, I wouldn't rely on the UHF, but would use the HF.
Cheers,
Roachie
AnswerID: 48124

Reply By: Hatcher - Thursday, Feb 26, 2004 at 09:10

Thursday, Feb 26, 2004 at 09:10
For everything you ever wanted to know about antennas try

http://www.arrl.org/tis/info/whyantradiates.html

or

http://www.arrl.org/tis/info/antheory.html#why

AnswerID: 48161

Reply By: CT - Thursday, Feb 26, 2004 at 14:30

Thursday, Feb 26, 2004 at 14:30
Roachie hit on a very important point with the mention of ground plane and ground plane independent. With a ground plane independent aerial, you can mount it anywhere on the car without compromising signal transmission and reception. If you have a ground plane dependent aerial (as most of the older models were), they work best when mounted in the most central position with regard to the amount of metal surrounding them. This made the best place to put them the centre of the roof for most wagons! Not always very practical.

I run a 6db GME groundplane independent aerial (white broomstick) that is capable of picking up the maleney repeater from Chermside in Brisbane's northern suburbs, so that will give you an idea of performance at the Sunshine coast. They have a spring base so flex out of the way nicely. You can also interchange the aerial on the base to swap between heights and gains.

Cheers
Craig
AnswerID: 48212

Follow Up By: tdcockers - Thursday, Feb 26, 2004 at 16:16

Thursday, Feb 26, 2004 at 16:16
do you mean you can hear it or open it? mind you, the maleny repeater is about 480ft above sea level, from memory...
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Follow Up By: CT - Thursday, Feb 26, 2004 at 16:46

Thursday, Feb 26, 2004 at 16:46
definately recieve, can't remember about transmitt (long time since I've lived in Brisbane and on the rare occasion I visit the UHF is off so I dont have to put up with the crap).

able to transmitt and recive on the ocean view repeater from Bribie.
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FollowupID: 310116

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