| Author |
Message |
    
Sparkomatic
| | Posted on Saturday, January 10, 2004 - 6:25 am: | 
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My son replaced his 1992 reg cab Ranger p/u with a 99 Supercab Ranger. He had a 7' Skipshooter on top of a diamond plate tool box with the 92.......SWR was flat on ch 20 with 18' of mini 8 coax. He remounted the Tool Box, antenna, coax, ect in the 99 and now the antenna is flat on 40 channels above 40 and 1.7 on ch 20. have we just entered the "Twilight Zone"? The adjustment on these antennas really doesn't improve anything.
Any ideas? The tool box is fastened to the bed with 2 stainless steel hex head self tappers. |
Ca346
| | Posted on Saturday, January 10, 2004 - 6:02 pm: |
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Maybe the bed is not 'as grounded' or connected to the frame as the old truck? Try running extra flat strap grounding to see if it brings the SWR down. It's worth the try.
I could get a better SWR sometimes by just moving the COAX around and watching the meter to find the sweet spot. |
Wildrat
| | Posted on Saturday, January 10, 2004 - 6:10 pm: |
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make sure things are grounded. Cab, tool box etc. |
Bigbob
| | Posted on Saturday, January 10, 2004 - 6:51 pm: |
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You icreased the mass of metal directly in front of and up the side(looking from the side of truck),I don't understand it well enough to explain it but you effectively shortened the radiator electrically,moving it's resonant frequency up about 455 khz,put the base of the antenna even with the top of the cab and you should be back in business,you may have to get a shorter antenna(physically)for clearance.Tech833 is the guy to ask he is top notch on antenna theory. |
Honkytonkman593
| | Posted on Thursday, January 29, 2004 - 10:55 pm: |
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i have a 2000 ford ranger and i tell you what the bed is mostly plastic!!! the only real metel is the bed bottom! i have a 102 inch stanless steel antenna off of the back corner of the box left side. it took 3 lag bolts to hit real metal and get it to ground, its a ford we have to deal with noise and bad grounds. good luck. ps try 9 feet of coax if you run it that close to the cab ...the coax might be rolled into a loop creating a coil which in turn messes up the match.....and a ground strap wont do very well on this vehical. honky tonk man 593 outta ny!! |
Tech833
| | Posted on Friday, January 30, 2004 - 2:11 pm: |
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The part of the bed that is vertical and behind the cab is metal. The interior bed lining is metal. Use double shielded coax and you should have little trouble. |
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