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#1
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I am going to a hamfest this weekend (Frostfest in Richmond, Va.) and would
like to get all the parts to assemble my mobile antenna. Okay, after reading many many threads on newsgroups and eham, I have still a couple of questions. I have a 2000 Dodge Caravan (I posted before and had many good responses!) and now my wife has said I can drill. Well, I will only be using the ic 2100 on road trips and the like. I have an ht for all other things. On road trips we use a "snail" on the luggage rack. Kind of hard to get the antenna there now. My only option is an adjustable angle mount on the hood, rear gate, or mounting the antenna to the frame under the front or rear bumper? My wife doesn't mind a 5/8 wave on the bumpers as long as it can be removed. Are there any mounts for the bumper? It is a plastic bumper and the metal frame is recessed about 6-10 inches up under the bumper. I guess a mag mount will work but just not as well as a mount that is drilled. Will the clamp mount work on the hood? Thanks 73 Greg |
#2
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Try the Comet 400 series mount. It's a bit pricy but is strong and very
adjustable. I use a pair of them on my van's hatch and can play mix and match. With the 3/8 x 24 mount, you can use hamsticks as well as vhf antennas. Time to sneak a '706 into the van? When you don't want antennas just cover the mounts with tubing caps (make it a tight fit) and you are all set until the next trip. Phil, KB2HQ "Greg Doughty" wrote in message ... I am going to a hamfest this weekend (Frostfest in Richmond, Va.) and would like to get all the parts to assemble my mobile antenna. Okay, after reading many many threads on newsgroups and eham, I have still a couple of questions. I have a 2000 Dodge Caravan (I posted before and had many good responses!) and now my wife has said I can drill. Well, I will only be using the ic 2100 on road trips and the like. I have an ht for all other things. On road trips we use a "snail" on the luggage rack. Kind of hard to get the antenna there now. My only option is an adjustable angle mount on the hood, rear gate, or mounting the antenna to the frame under the front or rear bumper? My wife doesn't mind a 5/8 wave on the bumpers as long as it can be removed. Are there any mounts for the bumper? It is a plastic bumper and the metal frame is recessed about 6-10 inches up under the bumper. I guess a mag mount will work but just not as well as a mount that is drilled. Will the clamp mount work on the hood? Thanks 73 Greg |
#3
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On Sat, 21 Feb 2004 08:08:23 -0800, Bill Turner
wrote: On 21 Feb 2004 00:07:50 GMT, ojunk (Greg Doughty) wrote: My only option is an adjustable angle mount on the hood, rear gate, or mounting the antenna to the frame under the front or rear bumper? _________________________________________________ ________ Why not a mag mount on the roof? It will work better than any of the above. You won't have to drill any holes if you route the coax through the door jamb. I've done that on many vehicles with no problems at all. You'd think the coax would get squashed when the door closes, but it doesn't; at least not enough to matter. Actually, many of the complaints made to this board often reveal that both the "thru-the-glass" and magmount are inferior to sheet metal mounted antennas. Both style certainly work, and well enough for most, but for those at the edges, they find much better performance from good solid metallic connections. On 2 meters, when you put an antenna down low, like on the bumper, two things happen, both bad: It becomes very directional due to the blocking effect of the car body, and it's ground wave coverage drops dramatically. Higher is better. Higher is always better, but I would dispute that the car body somehow "shields" an antenna (unless the antenna is butt up against the cab, say). More often than not, the favored direction (the major lobe) is found aligned in the direction of the most metal. That is, with a bumper mount or fender mount, the best propagation is corner to corner across the car NOT away from the car. In other words, the sheet metal of the body supports and favors lobe development (instead of the metal acting as reflector). I've noted this documented by QST since the '60s. 73's Richard Clark, KB7QHC |
#4
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#5
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You want that 2m antenna as high as possible. I think somebody makes a
luggage rack mount; or, you can make one yourself out of a 3 inch piece of angle iron, and a U bolt. Wish I had a luggage rack. I had a 5/8 2m antenna on a mag mount once, blew off on the Delaware Memorial Bridge. Tam/WB2TT "Greg Doughty" wrote in message ... I am going to a hamfest this weekend (Frostfest in Richmond, Va.) and would like to get all the parts to assemble my mobile antenna. Okay, after reading many many threads on newsgroups and eham, I have still a couple of questions. I have a 2000 Dodge Caravan (I posted before and had many good responses!) and now my wife has said I can drill. Well, I will only be using the ic 2100 on road trips and the like. I have an ht for all other things. On road trips we use a "snail" on the luggage rack. Kind of hard to get the antenna there now. My only option is an adjustable angle mount on the hood, rear gate, or mounting the antenna to the frame under the front or rear bumper? My wife doesn't mind a 5/8 wave on the bumpers as long as it can be removed. Are there any mounts for the bumper? It is a plastic bumper and the metal frame is recessed about 6-10 inches up under the bumper. I guess a mag mount will work but just not as well as a mount that is drilled. Will the clamp mount work on the hood? Thanks 73 Greg |
#6
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Higher is always better, but I would dispute that the car body somehow
"shields" an antenna (unless the antenna is butt up against the cab, say). More often than not, the favored direction (the major lobe) is found aligned in the direction of the most metal. That is, with a bumper mount or fender mount, the best propagation is corner to corner across the car NOT away from the car. In other words, the sheet metal of the body supports and favors lobe development (instead of the metal acting as reflector). I've noted this documented by QST since the '60s. 73's Richard Clark, KB7QHC I won't get into the method but it has a lot to do with the frequency and if the antenna is a full 1/4 wave, 5/8 , or longer co-linear antenna as to what the patern is. The patern can be over the longest metal path for a 10 meter whip or it can be "blocked' and go in the opposit direction for an antenna mounted on one side of the trunk of a car for a co-linear 440 mhz antenna. This is from the antenna makers diagrams and polar plots. I have observed by leaving a car in one spot and changing from a 1/4 wave, 5/8 wave and a 6 foot long colinear 2 meter antennas on the same mount that each can have a diffrant patern , especially where working repeaters and the repeater antennas are at differant heights. For the areas I am in , I would rather have a 1/4 wave in the center of the roof , but have settled for a 38 inch long colinear type dual band antenna on one side of the trunk of my car and not worried about it. |
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