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HF Mobile Antenna Mounted Front or Rear?
(QRZDXR2)
on
November 8, 2008
View comments about this article!
Mobile Mount, Front or Rear?
Ok we asked this question from some very well known mobile masters and didn't get much of an answer. Matter of fact we didn't even get a reply from the local web resident that is the expert for whatever reason, here is the question we asked.
Does it make a difference if the HF mobile antenna is mounted on the front of the vehicle or the rear?
We noticed that a lot of the AU and EU hams seem to prefer mounting the mobile antenna for HF on the left or right (depending on which side of the road you drive on) front. While the US hams seem to prefer the left rear for their HF mobile antennas.
We went to the K0BG web site and searched though its vast knowledge not finding an answer.
Some of the others we have talked to on the air seem to think the major reason that the EU/AU hams put the antenna on the front is due to shorter lead lengths. Others were more concerned about visual. Seems that they can see the antenna hitting low hanging limbs much easier than if it were on the rear of the vehicle.
Tuning was the other major issue. Again the EU/AU people seem to favor the not so expensive screwdriver type of antenna instead of the king's value. (Must mean more expensive and doesn't work as well.)
So what we are asking again is… What is the real reason for putting the antenna on the rear of the vehicle? Would it be better to have it on the front?
This article has expired. No more comments may be added.
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HF Mobile Antenna Mounted Front or Rear?
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by W8ZNX on November 8, 2008
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depends on which way the car is facing
how many angels can dance on the head of a pin ?
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RE: HF Mobile Antenna Mounted Front or Rear?
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by NV2A on November 8, 2008
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I'll bite.
I had my HF antenna on the back left side of the vehicle to keep it away from tree limbs that are more apt to be lower to the ground on the right side of the vehicle and engine noise.
My VHF antenna was in the middle of the roof to get a more symmetrical pattern.
As for why the back and not the front? Well, mostly aesthetics for me. I'm used to seeing them there as they "look" more streamlined. Whens the last time you saw a tuna boat with huge whips on the bow? LOL If one has any sense of art, balance or design they will tell you it just naturally looks better on the rear of the vehicle. In fact, I for one, would ROFLMAO if I ever saw one mounted on the front!
As for lead length, I don't think you could measure the difference in loss but I do think you could measure the difference in "noise" by mounting the antenna within inches of the motor and it's electronics. I used 1/4" healiaxe to mount my AH-4 tuner & whip on rear fender and I could barely hear the windshield wiper motor. It was a very quite installation.
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HF Mobile Antenna Mounted Front or Rear?
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by NY7Q on November 8, 2008
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My screwdriver antennas have always been mounted the same on all my vehicles. Below bumper, mounted with screws to the frame(mount bolted to frame)on rear of vehicles. Always worked the world with them.
Of course I only used one model, the BB-3, which is long gone now.
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RE: HF Mobile Antenna Mounted Front or Rear?
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by K0BG on November 8, 2008
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You didn't find an answer on my web site, because you didn't look in the right place.
When it comes to mobile antennas, especially HF ones, the biggest single factor in calculating efficiency is ground losses. Mounting an antenna on the rear of an SUV or van, especially when a trailer hitch mount is used, greatly increases the ground loss. How much? Depending on the installation, but as much as 2 to 3 times. Thus efficiency drops to single digits, on 20 meters, and sub-single digits on 80 meters.
The real key is, put as much mass under the antenna as you can, not along side! If you drive an SUV or van, the front is a viable alternative.
But, alas, when so many people rate their antennas by the number of DX contacts they've made, there isn't much one can do dispel their beliefs.
Alan, KØBG
www.k0bg.com
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RE: HF Mobile Antenna Mounted Front or Rear?
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by NA4IT on November 8, 2008
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Front mounting pros:
1. Easy to see
2. Easy to see when tuning
3. Easy to see when hitting low objects
4. Easy to see when it gets destroyed when having a wreck while looking at the antenna in 1-3 above.
de NA4IT
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RE: HF Mobile Antenna Mounted Front or Rear?
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by AA4PB on November 8, 2008
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I think Alan hit the nail on the head. You want as much metal under the antenna as possible and as little along side (think capacitive coupling here) as possible. Whether front or rear accomplishes that better depends on the vehicle design.
A secondary benefit to rear mounting (assuming a front mounted engine) is keeping the antenna away from the engine RFI.
In the U.S., left side mount keeps the antenna farther away from low hanging tree limbs and kids walking along the sidewalk when parked.
Keeping the feed line shorter doesn't matter much, especially on HF. The amount of loss in the length of coax needed to get from front to rear in a vehicle is pretty insignificant.
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HF Mobile Antenna Mounted Front or Rear?
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by K8YZK on November 8, 2008
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NA4IT, had a lot of pro's for front mounting, now the negative. It will be an obstruction to your vision which could be very bad, and could get you a ticket.
Kurt
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RE: HF Mobile Antenna Mounted Front or Rear?
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by VK6ZMS on November 8, 2008
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Anecdotically.... a rear mount is better to avoid the electrical noise from the engine bay.
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RE: HF Mobile Antenna Mounted Front or Rear?
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by G0OTT on November 8, 2008
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I didn't know we euro's mounted aerials on the front :)
I put my vhf/uhf in the middle of the roof, hf on a tow-bar mount at the rear.
Apart from the electrical/ignition noise already mentioned the only difference is the orientation of the groundplane(car/vehicle), rear favours the direction in front, front favours direction to rear.
Regards Dareen
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RE: HF Mobile Antenna Mounted Front or Rear?
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by KB9CRY on November 8, 2008
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Maybe they prefer the rear so that it doesn't block the drivers forward vision?
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HF Mobile Antenna Mounted Front or Rear?
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by WA1RNE on November 8, 2008
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Just curious, how is it that a person identifying themselves only by a "handle" can submit a front page article on eHam?
Similar to others who make anonymous comments, their credibility and experience comes into question; i.e., Are your questions and observations based upon your experience as a licensed ham or just a CB'er or shortwave buff?
On a secondary basis, this "article" is not an article per say and should have been submitted as post in the Elmers forum, yes?
....WA1RNE
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HF Mobile Antenna Mounted Front or Rear?
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by N8NSN on November 8, 2008
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I have a Texas Bug Catcher mobile antenna on the handlebars of my mountain bike. It is a real problem in high wind conditions. My forceps have really increased in diameter! It really stinks when I hit a tree limb in the forest and the bike pulls a hard left rendering me on my can at the edge of the trail.
LOL. Yea... NEXT !
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RE: HF Mobile Antenna Mounted Front or Rear?
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by K0BG on November 8, 2008
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I think folks put too much emphasis on RFI from the ignition system with respect to front mounting. Here's why.
The real culprit is the exhaust system, as it acts like an antenna for ignition RFI. If you properly bond the exhaust system, and the hood of course, the difference in RFI from the ignition system is all but moot.
Alan, KØBG
www.k0bg.com
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RE: HF Mobile Antenna Mounted Front or Rear?
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by K1CJS on November 8, 2008
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Considering the author, I'll give this one all the consideration here that it deserves.
......
Next article, please.
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RE: HF Mobile Antenna Mounted Front or Rear?
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by K0BG on November 8, 2008
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A few more comments.
If you really take the time to model an HF antenna mounted on the rear of a vehicle (it takes about 200 segments just to get close to the shape of a sedan), you would see a directional advantage in the pattern depending on where on the vehicle the antenna was mounted. However, it is very slight, and is seldom more than a dB or two. In fact, the difference is less than the instantaneous changes in propagation, and even changes in ground loss values from re-orientating the vehicle, that any observation postulating an advantage in any one specific direction is questionable.
From a subjective point of view, if you operate mobile long enough, you'll notice there are times when the signal strength seems to be opposite that of any an assumed directional advantage.
Another myth is that heavy traffic effects the efficiency. While it might effect the S+N/N ratio (extra ignition RFI for example), there are cases when other vehicles in close proximity actually increases the received signal strength. Any one who knows how antenna reflectors work would know why this is so.
Probably the most misunderstood differential is the reduction in efficiency low mounting (trailer hitch) offers verses high mounting (high on the quarter panel). When you tell folks it can be as much as 15 dB, their typical response goes something like this. "I can work everything I can hear". Or my biggest peeve, "It can't be inefficient, I worked 5 DX stations the first hour".
Alan, KØBG
www.k0bg.com
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RE: HF Mobile Antenna Mounted Front or Rear?
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by KF4HR on November 8, 2008
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First, who is QRZDXR2? No name or callsign? Don't worry no one will laugh at you (well almost nobody).
There's numerous articles on how placement of an antenna on a vehicle affects its radiation pattern and efficiency. You just need to do an internet search, or (if people still do this), maybe pick up a book on the subject.
KF4HR
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RE: HF Mobile Antenna Mounted Front or Rear?
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by WA5UHK on November 8, 2008
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I think the old saying goes like this, "opinions are like noses, everybody has one". Here's mine.
After three mobile installs over the last 35 years, I find that the direction of the most outbound rf (notice I didn't use the word gain) is toward the direction of the most metal. For an antenna mounted on the rear that means the best signal is toward the front of the vehicle.
The second best instrument I've owned is my field strength meter. You can use one with the help of a friend to see what you find. If you do, get a tall ladder or a tall tree your friend can climb and take the measurements at ground level and as high as your friend can climb.
BTW, the first best instrument I've owned is my antenna analyzer.
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HF Mobile Antenna Mounted Front or Rear?
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by K0RGR on November 8, 2008
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I had my HF mobile antenna front-mounted on my motorhome. The aluminum sides of the vehicle were too flimsy to support a decent antenna, even with some backing, so the front left fender was the next best choice. It worked fine...
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HF Mobile Antenna Mounted Front or Rear?
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by HP1KL on November 8, 2008
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I've noticed this "style" among international aid organizations in Central America -- i.e. International Red Cross, and so forth. Most of the time the antennas are mounted dead center & look awful... I have always imagined that it has mostly to do with being able to avoid striking tree branches, etc. Also, the low hood/bonnet can best serve as a ground plane, especially if it is not a pick-up truck.
In Ecuador, especially in Guayaquil, I noticed that 5/8 VHF and UHF antennas mounted on the hood lip, close to the windshield, right in the middle. First thing that comes to mind is radiation to driver and front seat passenger. Of course, not all hoods have enough clearance to allow full opening (without striking the windshield).
The Spanish-owned electrical power company here in Panama has 800-mHz "curly pig-tail" antennas mounted smack in the middle of the hoods on their pick-up trucks where, I guess, radiation is best.
73's - Tony/HP1KL
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HF Mobile Antenna Mounted Front or Rear?
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by KD8DEY on November 8, 2008
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Remember reading somewhere something about signal path....
If mounted on the left rear, best signal towards the front right, right rear best signal towards left front...rear center best signal towards front center...roof center more omnidirectional.....
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RE: HF Mobile Antenna Mounted Front or Rear?
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by W3LK on November 8, 2008
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<< Just curious, how is it that a person identifying themselves only by a "handle" can submit a front page article on eHam? >>
Because eHam doesn't care. It is the Jerry Springer of ham radio web sites.
73,
Lon - W3LK
Naugatuck, Connecticut
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RE: HF Mobile Antenna Mounted Front or Rear?
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by N3JBH on November 8, 2008
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"Because eHam doesn't care. It is the Jerry Springer of ham radio web sites."
Hey Hey now even Jerry Springer has some class :)
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RE: HF Mobile Antenna Mounted Front or Rear?
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by N8BOA on November 8, 2008
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Its simple
If you live in Australia then it has to go in th front but if you live above the equator then it goes in the back
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RE: HF Mobile Antenna Mounted Front or Rear?
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by N6AJR on November 8, 2008
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I like mine on the drivers side rear. couple of reasons, it can be seen in the rear view me=irror, it is away from the sidewalk and all the little grubby fingers who just have to twang it as they go by and the trees are taller in the middle of the street.
I dealy it shoud be mounted inthe center of the vehicles roof, but in some cases that brings up clearance problems. also on a car where you don't want to punch hole in th body, you can always slap a bar under the drivers side rear fram sticking out from under the body to attach the antenna too. sort of like a mini trailer hitch.
on my car it is an ATAS on the drivers left rear trunk lid sa the car goes in the garage and it clears the door. on the trucjk it is an original DK-3 and the truck parks outside so it stands much taller mounted on the drivers rear of the bed.
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RE: HF Mobile Antenna Mounted Front or Rear?
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by W7ETA on November 8, 2008
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Its much easy for me to have my antenna following me rather than have me follow my antenna.
73
Bob
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RE: HF Mobile Antenna Mounted Front or Rear?
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by W3LK on November 8, 2008
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<< Hey Hey now even Jerry Springer has some class :)>>
That's a matter of opinion, Jeff. ;)
73,
Lon - W3LK
Naugatuck, Connecticut
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RE: HF Mobile Antenna Mounted Front or Rear?
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by WB2WIK on November 8, 2008
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"I can work everybody I hear" no matter where my HF mobile antenna is mounted.
That's because I'm almost always noise limited when operating HF mobile!
I ran a 500W amp mobile for a couple of years until I kept getting e-mails from stations who called me who I never heard at all.
:-(
Never spent the hours it takes to abate all the noise; funny thing is, when I was /m with my Volvo for several years, my own vehicle wasn't making any of the noise bothering my receiver. I could turn the engine off, or start the car and rev the engine: No difference. Most of the noise was stuff "around" me, and although there are many clever ways to reduce that, I didn't implement them well.
I always figured the best mobile HF antenna would be my beam at home connected to a really long coax cable that could spool out and retract as I drove around.
:-)
WB2WIK/6
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HF Mobile Antenna Mounted Front or Rear?
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by KC0RBX on November 8, 2008
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The guy didn't use his callsign? Some of the posters on this article are giving him some guff for that?
I didn't realize a license was needed on the internet. Maybe a password here and there, but c'mon.
If the author is a C.B.er, at least he is trying to learn more, which is one thing hams criticise them for not doing to begin with.
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HF Mobile Antenna Mounted Front or Rear?
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by N0AH on November 8, 2008
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I'd choose my grounds before location on a mobile.....I have a pick up. Antenna is on inside of truck bed above wheel weld. I have over 20 ground straps between doors, the car hood, body framing, shocks, etc.....and my tarheel antenna is working ust fb. Directionality was very much towards the front until I gounded everything together. It does favor a bit towards the front but nothing like it used to-
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THAT IS A GOOD ARTICLE
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by PLANKEYE on November 8, 2008
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I liked it. I never thought much regarding placement.
OM I hope you get some info here, alot of these folks have alot to contribute.
I liked the coax spool on the back of the car hooked up to the beam. That was good WIK. Wish it was that easy though.
Keep the Beer out the Finals Fellas!!
Best 73 ES God Bless!!
PLANKEYE
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RE: HF Mobile Antenna Mounted Front or Rear?
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by WV4L on November 8, 2008
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Agreed on the grounding. It is a must. Like previously stated, try and get as much of the vehicle under the antenna as possible and make sure all those parts are grounded and bonded. Taking that into account I mounted my antenna on the center bed rail of my pick-up.
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RE: HF Mobile Antenna Mounted Front or Rear?
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by PLANKEYE on November 8, 2008
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K1CJS SPEAKS:
Considering the author, I'll give this one all the consideration here that it deserves.
......
Next article, please.
_________________________________
THIS IS PLANKEYE:
What's up dude, you got a clay sculpture of yourself on the mantel with a pipe and a D-104?
How do you know the author?
Keep the Beer out the Finals Fellas, I got to go!
PLANKEYE
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HF Mobile Antenna Mounted Front or Rear?
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by KD6HUC on November 8, 2008
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I always thought that away from a noise producer like the engine compartment was a good idea. Spark plugs and all other noisy electronics.
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RE: HF Mobile Antenna Mounted Front or Rear?
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by PLANKEYE on November 8, 2008
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WA1RNE IS ON A ROLL:
Just curious, how is it that a person identifying themselves only by a "handle" can submit a front page article on eHam?
Similar to others who make anonymous comments, their credibility and experience comes into question; i.e., Are your questions and observations based upon your experience as a licensed ham or just a CB'er or shortwave buff?
On a secondary basis, this "article" is not an article per say and should have been submitted as post in the Elmers forum, yes?
....WA1RNE
______________________________________
THIS IS PLANKEYE:
Just curious, how is it that so many folks here that have legimate Calls can post so much HATE and DISCONTENT?
If you do that enough, your experience and credibility come into question!
Right or Wrong?
I gotta go Dudes!!
Keep the Beer out the Finals Fellas!!
PLANKEYE
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RE: HF Mobile Antenna Mounted Front or Rear?
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by W5FYI on November 8, 2008
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It seems to me my dad mounted the antenna on the rear left quarter panel more or less because he had the matching section, amplifier, and dynamotor in the trunk. And I think the old police radios were also mounted in the trunk, and it was just easier to run the feeder through the quarter panel. Maybe it was because the first people who mounted antennas did it on the back of the car, and everyone else followed suit because it seemed to work.
Like the guy who asked his wife why she cut a piece off the end of a roast before she cooked it. "Because my mother always did," was the reply. When he later asked the mother-in-law, she said. "Because my mother always did it." Finally, they asked the great-grandmother-in-law and she said, "Because our ovens were a lot smaller back in those days." See, there's a reason for everything.
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RE: HF Mobile Antenna Mounted Front or Rear?
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by N5BEW on November 8, 2008
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I used a Henry Allen coil a 3 ft base and a 5 ft whip on my old 1989 Dodge Caravan worked and tuned well. I had the coil a ways away from the roof line. I mounted it to the metal front bumper on right side. If your using a bugcatcher antenna why are you worrying how it looks.
I also had a Webster Bandspanner in the same spot also.
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RE: HF Mobile Antenna Mounted Front or Rear?
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by WA1RNE on November 8, 2008
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THIS IS PLANKEYE:
Just curious, how is it that so many folks here that have legimate Calls....
>>> Per your advice, I had to stop right there as it didn't make sense to repeat another word you posted.
One would think that if a person is GENUINELY interested in amateur radio and has something worthwhile to share, be it a question, an opinion or a suggestion - even if on occasion it means crossing what is known to some as that dreaded, black hole of the universe known as constructive criticism - they should have nothing to hide and simply post with a call sign. With that, I know the person is serious about what he/she is saying, and/or if they're expressing an opinion I have some sense of how informed they are about the subject.
Yes, that's right, if you chose to write an article or opinion piece on eHam and say that all vertical antennas are trash and your license just hit the mailbox 1 week ago, I have a better idea where you're coming from.
So how serious should we take the next post that's signed by "CQ-SpongeBob" or "QSLGumby" ??
More accurately, maybe "QCX-Gumby"?
On the other hand, this forum isn't supposed to be a YouTube blog for cartoon characters....
QRJ???
...WA1RNE
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RE: HF Mobile Antenna Mounted Front or Rear?
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by VK6ZMS on November 8, 2008
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"Its simple
If you live in Australia then it has to go in th front but if you live above the equator then it goes in the back "
Come to thing of it most of the mounts I have seen here are on the rear.
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RE: HF Mobile Antenna Mounted Front or Rear?
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by W9OY on November 9, 2008
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I don't know about front or back but I have found it better to mount the antenna on TOP of the vehicle even though the most metal is on the bottom. Whenever I mounted it on the bottom I didn't get out very well.
My guess is mounting it on the front would allow for for successive wave fronts to constructively add up when you hit a sweet spot of speed and you would get about 3dB of gain in the direction of travel. If you mounted it on the back it would cause destruction and that is why mobiles tend to fade all the time. You can reverse this phenomena by driving in reverse if you are mounted on the rear.
73 W9OY
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HF Mobile Antenna Mounted Front or Rear?
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by W0FEN on November 9, 2008
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It depends on several things.
Where can you get the most ground plane? Which is most clear of other objects? Do you want the optimum radiation and reception?
Do you mind seeing an antenna while driving?
Do you own an SUV, van, or truck? Do you park your vehicle in a garage?
One last consideration. Do you run high power >100W?? If so, mount it as far away from your body as possible particularly at VHF frequencies.
Answer all the questions and your location will be obvious.
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HF Mobile Antenna Mounted Front or Rear?
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by N6JSX on November 9, 2008
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Much in the USA depends on the State vehicle laws >Beware<, like:
1. Unobstructed view of the road - front mounting could be a violation just like radios mounted on top your dash in the windshield area.
2. Overhang of the right & left sides of the vehicle - on right typically not past the plane of your outermost right side mirror. On the left no more than 6" (and some States will go as far as 12") from the left side plane (not the mirror) of the vehicle.
Safest is rear mounting that big HF antenna but make sure the top most element does not exceed 12' from the ground or you will hit/tickle the underside of some bridges (I just went under a 11'6" RR bridge in PA tickling the underside - rare) and many drive-thru's.
I forget which State I was in but there is a mid-western State that has some type of "road hazard law". I got pulled over for having a 5-band Hustler HF combo antenna using a VP1 plate (looked like a Spider) HF antenna. The Trooper stated it looked like it could snap off becoming a road hazard - until he saw that I also had a guy rope connected between my roof rack and VP1 plate (where all the wind loading would occur), guess he didn't like the whips bouncing around above the thin 5' Hustler spacer; the antenna worked great but band limited!
I now sport a screwdriver mounted on my spare tire bracket of my SUV. The solid chromed steel bracket I fabricated myself. I still use a guy rope just to minimize the overall wind loading strain to the antenna/bracket/vehicle. Can be seen in my group:
http://groups.yahoo.com/group/RDF-USA/files/Antennas/Misc/
Here is a follow up subject to this topic;
"Do Mobile HAM antennas scare deer away?"
Many will say no way but I've had some serious luck with antlered horses they call deer that grow in OH/IN/PA. They seem to avoid me and swiftly go the other way when my car approaches at speed (as I hit the brakes and push my heart back into my chest). I wonder if the "various" HAM antenna lengths (I sport on my vehicle) create multiple low frequency noises that bother deer to the point they want to avoid the noise source. I've seen the high frequency bumper wind screecher's and told they do not work - but maybe its our multiple low frequency noises getting to those big ears that makes the difference? Another great reason to be a mobile active HAM!
Kuby, N6JSX
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RE: HF Mobile Antenna Mounted Front or Rear?
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by KD8DEY on November 9, 2008
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I prefer to mount from the rear. It makes things simpler for me.
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HF Mobile Antenna Mounted Front or Rear?
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by WB8UHZ on November 9, 2008
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Six of one and half a dozen of the other. If you put the antenna on the front right, the best signal will be to the left rear. If you put the antenna on the left rear the strongest signal will be to the front right.
tim
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RE: HF Mobile Antenna Mounted Front or Rear?
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by AA4PB on November 9, 2008
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My guess is mounting it on the front would allow for for successive wave fronts to constructively add up when you hit a sweet spot of speed and you would get about 3dB of gain in the direction of travel
------------------------------------------------------
Of course you've got to drive a bit faster than 186,000 miles per second - but at that speed you'll never get pulled over for a speeding ticket :-)
I'm not sure the typical vehicle is large enough to give any directional characteristics to an HF antenna. At least I have never noticed any significant signal strength change when turning.
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THAT WAS HORRID
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by PLANKEYE on November 9, 2008
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DUDE?
Spongebob makes more sense than 90% of most folks that post here.
And 90% of folks that post here do it with a Call.
Now THAT is Ironic!
Like a free ride when your already there.
Dude that was Horrid!!
Your thinker aint firin!
You still owe me breakfast Ray, your buyin though you-son-of-a-gun!
I got to go fellas!!
Keep the chaw out the D-104 screen!!
PLANKEYE
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HF Mobile Antenna Mounted Front or Rear?
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by N0LOH on November 9, 2008
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I have mine mounted on the trunk lid on the passenger (right-hand) side. That way it avoids the awning at the drive-thru window, mostly for KFC, Wendy's and Taco Bell. McDonald's on the other hand, usually has a portico that covers the whole vehicle.
Also, since I'm using a rig with the control head separate from the RF unit in the trunk my coax lead is only four foot.
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HF Mobile Antenna Mounted Front or Rear?
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by G0GQK on November 9, 2008
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Makes no difference front or back but usually those north of the Equator have the antenna on the back, and those south of the Equator have it on the front. Not having lived below the Equator I think its because the sun doesn't cast a shadow on the windscreen below 0
( For anyone lacking humour, I'm quite normal !)
G0GQK
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RE: HF Mobile Antenna Mounted Front or Rear?
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by N8TCZ on November 9, 2008
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Being the antenna nonexpert that I am I agree with KD8DEY. Going back to the old (I hate to mention here) days of CB it was always understood that the radiation of the antenna is in the direction of the mass of the vehicle. Thus an antenna mounted on the rear gives you the best pattern to the front which in those days you tried to mount the antenna on the right rear which would give you the best pattern to the traffic coming at you in the opposing lane. It really didn't make that much difference though.
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HF Mobile Antenna Mounted Front or Rear?
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by KB4QAA on November 9, 2008
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Just depends on whether you need a curb marker or a dune flag. ;-)
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HF Mobile Antenna Mounted Front or Rear?
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by W3HR on November 9, 2008
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I know of some CB Extras who would believe you have to put the antenna on the rear, to keep that RF from blowin' back on ya!
>>Because eHam doesn't care. It is the Jerry Springer of ham radio web sites. <<
ROFL!! It's not that bad, is it? ;)
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RE: HF Mobile Antenna Mounted Front or Rear?
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by W4LGH on November 9, 2008
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Why should it make ANY difference, as long as you have as good of ground to your car as possible. Dead in the center of the roof SHOULD be the best location, but very impractical, especially when you drive a SUV like me!
This is like asking,"If I mounted my antenna upside down, would it still WORK?"
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RE: HF Mobile Antenna Mounted Front or Rear?
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by N5BEW on November 9, 2008
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The Aussies mount them that way just to tick off anal
retentive US hams.
KC5OU
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RE: HF Mobile Antenna Mounted Front or Rear?
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by N4CQR on November 10, 2008
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RE: ........just to tick off anal retentive US hams.
That's funny! I bet a couple of resident experts just got ticked off too.... :)
Good one - 73 C r a i g
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RE: HF Mobile Antenna Mounted Front or Rear?
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by K1CJS on November 10, 2008
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WA1RNE said:
".....One would think that if a person is GENUINELY interested in amateur radio and has something worthwhile to share, be it a question, an opinion or a suggestion - even if on occasion it means crossing what is known to some as that dreaded, black hole of the universe known as constructive criticism - they should have nothing to hide and simply post with a call sign....."
You would believe that would be the proper way to do things, but some people here--aided by the policy of e-Ham--are anything but, and hide their cowardice behind handles instead of identifying themselves.
One thing about wrestling with a pig in their sty--you get dirty and disgusted while the pig enjoys it.
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RE: HF Mobile Antenna Mounted Front or Rear?
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by WA1RNE on November 10, 2008
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One thing about wrestling with a pig in their sty--you get dirty and disgusted while the pig enjoys it.
>>> Usually the mud just slides right off, but every once and a while, it doesn't hurt to "Swing with the Swine"....
...WA1RNE
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RE: HF Mobile Antenna Mounted Front or Rear?
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by 29ID016 on November 10, 2008
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...OK guys "honi soit qui mal y pense" now i got that out of the way!! i have my antenna mounted at the rear of my 4wd as it to big otherwise but if i were to be static mobile or portable i would have it mounted in the middle of the roof. whats with all the bashing of cb i was once one and so were many of the rest of you! Im a ham and still use 11m i did not foget were i came from. A lot of the people who use that band are as good as we are and have respect for hams as they would not use our bands. The rant at the start of this post means .."shame be to him who thinks evil of it!" LET PEOPLE GIVE AN ANSWER TO THE GUYS QUESTION AND NOT LET IT GET DOWN TO HANDLES OR THE CB. EI6GTB TONY
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RE: HF Mobile Antenna Mounted Front or Rear?
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by W8RPE on November 10, 2008
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Regarding the mystery of the author of this post..it's obvious that there are more than one. They refer themselves as "we", several times. Possibly an indivudual(s) with a personality disorder or just a garden variety demonic posession.
Either way it's a good question, wrong forum but good question,
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RE: HF Mobile Antenna Mounted Front or Rear?
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by 29ID016 on November 10, 2008
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While i do agree to the previous post as "TO A GOOD QUESTION,WRONG FORUM BUT GOOD QUESTION"
We often refers to the "reader or author, but in his case it is sometimes used as in the patronizing we in stead of you or me. this usage is emotionally non-neutral and usally bears condescending,ironic,praising or some other flavour depending on an intonation; like "arent we very smart"?
CAN WE NOT JUST ANSWER THE QUESTION THAT PEOPLE ASK.
As for garden or what ever demonic possession, come on i live in ireland we are all saints.
now im going as low as you to even reply to your last post.
lets just answer the questions people ask! I STILL THINK IN THE MIDDLE OF THE CAR IS BEST. HI HI
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RE: HF Mobile Antenna Mounted Front or Rear?
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by W5WSS on November 10, 2008
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Why wouldnt any amateur serious enough to install an hf mobile antenna take the middle of the rooftop as the primary locale for the usually disadvantaged small,low height, vertical radiater? It is not too difficult to do an excellent installation. I installed mine located thru the middle of the roof top and finished the coaxial cable install behind the car body interior finish, the only place that the coax is revealed is where the 3 ft. extra slack is located to connect to the radio equipment near the operator. The time taken to implement these techniques is worthwhile. I admit I was a little reluctant but once I started I was able to work it out and the attention to detail reaps rewards in performance too. I needed to remove a circle of interior head liner where the ball mount backing plate would be located and access to tighten the thru bolts after completing the work I made a cover that borrowed the extra bolt length and fastened the cover plate that matches the head liner and voila! Oh and the mobile antenna that currently occupies the best location is an 9' Stainless Steel whip.I used a sealant to add additional water proofing at the mount location and never have any water leaks over the past three years. I am ready for 10m to open...the quarterwave works very well from a local hilltop here. So go for it when feasable. *Ps the Hustler heavy duty ball mount is reasonably efficient for hf and when combined with a tuner one can easily change antennas and use the same ball mount for most whip type antennas but remember to be reasonable do not exceed the load requirements of the ball mount. I have an Icom 718 and the LDG 200 pro auto tuner and the Tokyo High Power Hl 450b Amplifier for lightning fast band change if I want to...but I will not rely on one antenna fits all performance just me I guess. Middle of the roof for me.Good mobiling! Regards w5wss 73
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RE: HF Mobile Antenna Mounted Front or Rear?
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by W5WSS on November 10, 2008
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wb2wik/6 Yeah noise is an issue when cards arrive to verify ones shortcomings. I tell you noise is not an issue up on the hill top here....I was relaying dx for net control stations located across the country the other day for the 14.244.5 dx net hehe. I was using my full size quarter wave ground plane with four full size elevated sloping radials that is mounted on my vehicle for stationary hilltopping work. yeah yeah oh it was just band conditions....uhuh. 73
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HF Mobile Antenna Mounted Front or Rear?
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by KI6JUU on November 10, 2008
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When I used to install mobiles in Public Safety vehicles, (about a 100 years ago) we placed them on the left rear fender to 1. reduce the coax loss because the radio was in the trunk and 2. the officer was able to disconnect the antenna from the antenna gutter clip when he went out from the parking garage ( the antenna was so long that it reached from the fender to the driver's window) and 3. the left rear fender kept the antenna away from the tree limbs and moronic kids
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RE: HF Mobile Antenna Mounted Front or Rear?
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by KL7IPV on November 10, 2008
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I have used VHF & HF mobile antennas since 1966. They have been mounted in the center of a roof of a station wagon. One on the rear left side of a minivan. One on the front bumper of a 1T Chev PU truck. One on the trunk of a sedan. One now on a toolbox in the bed of my PU truck. Others in various places on the rear bumper. In all instances they worked well and I haven't seen enough difference to say where to mount them except that you mount them where it is convenient for the vehicle you use. I mostly try to mount them on the driver's side of the vehicle just so people walking down a sidewalk aren't inclined to pull on the antenna to rip it off or just screw around with it.
Frank
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HF Mobile Antenna Mounted Front or Rear?
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by KB4WEC on November 11, 2008
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I'm not a big HF mobile operator, but when I do I have GREAT success.
Here's my set up. (not for everyone!)
I use a single band MFJ 9440 @ 12 pep. and a 40 meter hamstick with w MFJ matching tuner for the 9440.
I have a mag (3 mat type) mount and install stick on the top of my SUV. sure it hit some small low hanging at times if I drive through or along a small two lane road, most of my trip is on larger freeway's and good road.
I can talk to ANYONE I can hear with 12 watts and a ham stick !!
Think what Allen said about the mass of metal below the stick is the reason for my success.
Can not tell you how many have questioned my power level and antenna setup.
Bottom line, the roof is the best place. Like I said, it's not the place for everybody.
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HF Mobile Antenna Mounted Front or Rear?
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by KI4SDY on November 12, 2008
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The left rear bolted under the bumper with a flat metal piece has worked best for me with hf antennas. It is the farthest point away from engine generated electrical noise (forgot about that, didn't you?). Clean reception is the most important factor in mobile operation. If you can't hear them, you can't talk to them!
In this location, the greatest antenna gain is thrown toward the front, which makes it easy to aim the vehicle for good contacts. Just point your vehicle in the direction you want to talk.
From a safety factor, the antenna is mounted lower to clear obstructions under the bumper. On the left rear, it does not obstruct the U.S. drivers front or rear view and may prevent you from getting a ticket from the revenue hungry cash registers with a badge.
Lastly, it looks normal on the rear, rather than making your vehicle look like an ugly mechanical rhinocerous. Your wife and or girlfriend won't be pleased if you mount it on the front bumper, take my word for it!
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HF Mobile Antenna Mounted Front or Rear?
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by WA3SKN on November 12, 2008
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This is an ARTICLE???
The original reason for rear mounting was to get the antenna away from ALL the various noises inside the engine compartment.
Front mounting was for shorter, lower loss cabling.
Both require extensive work for good HF operations!
73s.
-Mike.
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RE: HF Mobile Antenna Mounted Front or Rear?
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by K7LRB on November 12, 2008
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Mini-van; middle of the top of the roof; GREAT!
ibbidy ibbidy ibbidy .... that's all folks!
73,
de Larry
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RE: HF Mobile Antenna Mounted Front or Rear?
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by W0FM on November 13, 2008
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Think "Replacement Cost".
It will cost you less to replace your rear mounted antenna if the other guy hits your vehicle head on. Just the opposite if you get rear-ended.
:o)
73, Terry, WØFM
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RE: HF Mobile Antenna Mounted Front or Rear?
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by KQ6XA on November 13, 2008
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On pickup trucks, SUVs, and station wagons, the front mount simply works better for HF.
That's why you see HF antennas on the front of 4WD vehicles for many relief and aid organizations in various parts of the world.
On a sedan or coupe, it doesn't matter.
In USA, there is the legal concern that the Local Police, Highway Patrol, or State Police would issue a citation for "Obstruction of the Driver's View" if they were to see a big screwdriver antenna mounted on the front bumper. It also is a safety concern.
Hence, all my USA vehicles have mobile HF antennas mounted to the side, top, or rear, to avoid obstructing the driver's view.
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RE: HF Mobile Antenna Mounted Front or Rear?
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by WW0H on November 13, 2008
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"How many angels can dance on the head of a pin?"
Angels are spirits. They do not take up space and have no physical body. Thus, all of them can dance on the head of a pin.
Rev. John A. Ryding
WW0H
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RE: HF Mobile Antenna Mounted Front or Rear?
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by WW0H on November 13, 2008
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"How many angels can dance on the head of a pin?"
Angels are spirits. They do not take up space and have no physical body. Thus, all of them can dance on the head of a pin.
How's that for changing the subject? :)
Rev. John A. Ryding
WW0H
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RE: HF Mobile Antenna Mounted Front or Rear?
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by IRABREN on November 13, 2008
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"I prefer to mount from the rear. It makes things simpler for me"
I agree with that guy ! I'm old and the viagra helps too !
My antenna works great no matter where it is mounted, but only when the band conditions are good." I can work everything I hear" AND I "make lots of dx contacts"
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HF Mobile Antenna Mounted Front or Rear?
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by IV3SBE on November 16, 2008
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Hi this is 5z4es in disguise.....
In Africa we mount all HF antennas on the front of the vehicle for the following reasons:
1: Being the bonnet lower than the rest of the body, gives better space clearance to the antenna and better swr management equal to better performance ( pse see wwwo.sgcworld.com for some really good tips on this)
2: Helps negotiating rough roads while off road.
3: Bouncing left and right keeps road side cattle and locals away from your way.
4: We know is there as nobody had stolen it....yet.
5: Helps you not to touch live electrical overhead wires with the whip...
KWAERI!!!
5z4es ( ex iv3sbe) Enrico Nairobi Kenya
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RE: HF Mobile Antenna Mounted Front or Rear?
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by KB3MMX on November 17, 2008
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EXACTLY !!
What Alan said(below):
You didn't find an answer on my web site, because you didn't look in the right place.
When it comes to mobile antennas, especially HF ones, the biggest single factor in calculating efficiency is ground losses. Mounting an antenna on the rear of an SUV or van, especially when a trailer hitch mount is used, greatly increases the ground loss. How much? Depending on the installation, but as much as 2 to 3 times. Thus efficiency drops to single digits, on 20 meters, and sub-single digits on 80 meters.
The real key is, put as much mass under the antenna as you can, not along side! If you drive an SUV or van, the front is a viable alternative.
But, alas, when so many people rate their antennas by the number of DX contacts they've made, there isn't much one can do dispel their beliefs.
Alan, KØBG
www.k0bg.com
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RE: HF Mobile Antenna Mounted Front or Rear?
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by KD3JF on November 18, 2008
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The real reason for putting your antenna on the left is to stay away from interference from telephone poles with wire, cables, etc.
For the last few years I have placed the antenna in the center of the rear of the vehicle using the trailer hitch for a mount. Have worked loads of DX from Maryland using this position on 20 meters.
Paul Gates KD3JF
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RE: HF Mobile Antenna Mounted Front or Rear?
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by ZS6AZV on November 18, 2008
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Hi OM
Many of us started off with CB etc., don't be so hard on the "call sign-less" guy. We would'nt like to be called "snobs " ?
73
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HF Mobile Antenna Mounted Front or Rear?
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by WA4JM on November 20, 2008
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My antenna is mounted on the left rear side of my Dodge minivan. I found that when it was on the right side I was always hitting trees. The antenna is a Texas Bug Catcher. Not much noise pick-up and works great. Loss on RG8X is a non-issue.
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HF Mobile Antenna Mounted Front or Rear?
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by NK5G on November 20, 2008
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My HF mobile antenna is mounted on the truck...I work everyone I hear and I have also worked 5 DX stations in an hour...even more during a contest.
I have not found any significant directivity issues having the antenna mounted on the rear as opposed to the front or on top and it really does not matter. We all know that HF mobile antennas will not work like the one in the back yard. Put it on and have fun.
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HF Mobile Antenna Mounted Front or Rear?
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by KD3V on November 21, 2008
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Dead center is always best. Do all you cen to get it centered.
My 7in1 Hamstick tree works on the apartment roof as well as on the car. I only drive with 2 or 3 whips but when parked on the hilltops it is great to have 7 bands usable without a tuner being needed!!
my article on eHam.net gives details. Be sure to get the whole link.
http://www.eham.net/articles/5087?ehamsid=545f2b4754a8dc13f55cbde38c10513e
If you want more photos of the car installation, just ask me.
Dave kd3v@hotmail.com
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RE: HF Mobile Antenna Mounted Front or Rear?
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by WB6DGN on November 25, 2008
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"Many of us started off with CB etc., don't be so hard on the "call sign-less" guy. We would'nt like to be called "snobs " ?"
One of the guys I worked with, an experienced LMR field tech. was also an avid CB'er. When he was asked why he didn't get his ham license, obviously very easy for him to do, his reply was, "I don't want to have to put on a suit and tie every time I get on the radio."
Anybody need an explanation?
Tom
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by N4KRA on November 25, 2008
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My screwdrive is on the right rear bumper of my F-250 for specific reasons. One, is that I can see the weather tube in relation to the reflective tape I use for freq. markings. Two, I am able to go thru fast food drive in lanes with no problems, I clear the over hangs of the eaves. Three, I ran the cables before I mounted the antenna with out first thinking of my routing. Yep, I messed up... and Fourth, I had the antenna on the left rear bumper and was never really happy with it there on my F-150 I had previously.I found myself removing the whip more than it was worth to me...just to clear some obstacle.
But, in the end, it is up the the individual to decide on their preferences as to how to locate the antenna and then install it. I cannot make your decision for you, but just throw out some ideas why I did it as I did for your concideration..
Happy Mobileering with your new setup.
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RE: HF Mobile Antenna Mounted Front or Rear?
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by N0EQ on November 27, 2008
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k0bg wrote:
"...But, alas, when so many people rate their antennas by the number of DX contacts they've made, there isn't much one can do dispel their beliefs..."
And, alas, when so many people rate k0bg as some kind of ultimate authority on antennas, rather than simply ask "did I make the contact", there isn't much one can do [to] dispel their beliefs.
It obviously appears that some discussion moderators are snoring so heavily on k0bg's opinions, that they not only don't welcome conflicting opinions, they simply delete them.
Craig 'Lumpy' Lemke
www.n0eq.com
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