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Post by cbrown on Mar 25, 2015 8:25:35 GMT -5
Yea, with a couple of kilowatts running through it you can cook a dozen dogs at a time, and be the life of the picnic.... Sounds like a good way for someone to make the money back that they wasted buying that antenna in the first place.
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Post by BBB on Mar 30, 2015 9:51:14 GMT -5
A local operator (Tickle) was experimenting with a mobile directional set up last night. I think he put up a vertical antenna on his trailer hitch that was a bit higher than his roof mount antenna on his PU truck. Sure enough it was somewhat directional as witnessed when he would turn his truck in different directions, the signal would drop or increase a few S units for me and others.
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Sandbagger
Administrator/The Boss
Posts: 6,247
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Post by Sandbagger on Mar 30, 2015 11:20:18 GMT -5
A local operator (Tickle) was experimenting with a mobile directional set up last night. I think he put up a vertical antenna on his trailer hitch that was a bit higher than his roof mount antenna on his PU truck. Sure enough it was somewhat directional as witnessed when he would turn his truck in different directions, the signal would drop or increase a few S units for me and others. I was listening when he went from the single antenna to the reflector added. His signal went from a needle's width over S7, to about an S7 1/2. Not a huge amount, but certainly noticeable. But like you alluded, if you concentrate more signal in one direction, you take it away from another. I've never understood the desire to make a mobile more directional under normal conditions, since mobiles are always changing direction, and a directional pattern will only exacerbate signal rise/fade.
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Post by BBB on Mar 30, 2015 12:09:21 GMT -5
I've never understood the desire to make a mobile more directional under normal conditions, since mobiles are always changing direction, and a directional pattern will only exacerbate signal rise/fade. Ditto...although I understand some folks don't have the site to run a base station with a directional beam antenna.
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Sandbagger
Administrator/The Boss
Posts: 6,247
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Post by Sandbagger on Mar 30, 2015 12:28:07 GMT -5
I've never understood the desire to make a mobile more directional under normal conditions, since mobiles are always changing direction, and a directional pattern will only exacerbate signal rise/fade. Ditto...although I understand some folks don't have the site to run a base station with a directional beam antenna. Yea, I get that whole "keydown" aspect, where you want to focus as much of your signal as you can, in the direction of the signal judges and watergates, or the guy who wants to park up on a hill and work the long distance shots. But you don't want a directional setup when you are moving.
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Post by tecnicoloco2000 on Mar 31, 2015 1:07:36 GMT -5
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Post by BBB on Apr 2, 2015 10:34:00 GMT -5
Tickle was trying his mobile set up again last night and as he was turning his truck around I heard several definitive spikes in his transmitted signal. I'm assuming these where what are called "lobes" as I see when an antenna is plotted on a graph.
I want to plot my mobile antenna set up. I have two sliding ladder racks on the back of my pick up truck bed that are isolated from the truck by plastic rail sliders and want to see if grounding them has any effect on the directionality of the set up.
What's the best way to plot the horizontal lobes of an antenna? I have recently acquired the MFJ 259B unit and also have an old RS Field strength/SWR/Power meter that utilizes a small vertical wire antenna that mounts on top of the unit. Is it as easy as just walking around the truck while keyed with some plotting paper and mark what strength the signal is every few feet at lets say at a 20' then 40' then 60' radius?
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Sandbagger
Administrator/The Boss
Posts: 6,247
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Post by Sandbagger on Apr 2, 2015 10:55:07 GMT -5
Tickle was trying his mobile set up again last night and as he was turning his truck around I heard several definitive spikes in his transmitted signal. I'm assuming these where what are called "lobes" as I see when an antenna is plotted on a graph. I want to plot my mobile antenna set up. I have two sliding ladder racks on the back of my pick up truck bed that are isolated from the truck by plastic rail sliders and want to see if grounding them has any effect on the directionality of the set up. What's the best way to plot the horizontal lobes of an antenna? I have recently acquired the MFJ 259B unit and also have an old RS Field strength/SWR/Power meter that utilizes a small vertical wire antenna that mounts on top of the unit. Is it as easy as just walking around the truck while keyed with some plotting paper and mark what strength the signal is every few feet at lets say at a 20' then 40' then 60' radius? It is far easier to walk in a perfect circle around the vehicle, than it is trying to rotate a vehicle in a similar circle. But you can't get too close or you will be affected by near field energy. Try to be at least 50 yards away. The farther the better, within practical limitations.
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