TheFatMacgyver Posted January 29, 2015 Share Posted January 29, 2015 (edited) Hey guys so I had a quick question about the spare tire holder. Does anyone know if the "bushings" where it swings out are rubber or metal? I want to mount my CV antenna there and have already trued but was wondering if it was a good enough ground for it. I've seen members on here mount there their but never really seen feedback on if it works well there. By the way its a 102" whip antenna hooked up to a uniden 520xl CV. Only reason I ask is because my spr's are 2 and e rrytime I go to do a radio check it jumps to a 4 which is bad. Edited January 29, 2015 by TheFatMacgyver Link to comment Share on other sites More sharing options...
ahardb0dy Posted January 29, 2015 Share Posted January 29, 2015 The bushings are actually a pin, and it is metal, see here: http://faculty.ccp.edu/faculty/dreed/Campingart/nistail/ The 102" whips are designed to be mounted on the bumper, it really is too long to mount higher. Make sure the cable you are using is in good shape. The 102" whip is the only antenna that doesn't need to be adjusted, it's the proper length to give a good SWR reading. Link to comment Share on other sites More sharing options...
TheFatMacgyver Posted January 29, 2015 Author Share Posted January 29, 2015 Thanks ahardbody for the good information. Looks like I need to figure out why else it has high readings then since its no the antenna. Maybe add a spring to it? Link to comment Share on other sites More sharing options...
ThaBigPerm Posted January 29, 2015 Share Posted January 29, 2015 I mounted mine using a 90 degree bracket. Near the top hinge on the tire rack is a sheet metal "web" that I drilled for mounting, and got 1.5 SWR on 1 and 40 without running a dedicated ground from the bracket to the chassis. Not the best SWR in the world, but not bad. Cobra 18 WX ST II on a generic coax, generic 90 degree bracket, generic spring, and a 4' Firestick II. Worked great until excessive whipping on the trails busted the conductor inside the spring Link to comment Share on other sites More sharing options...
Precise1 Posted January 30, 2015 Share Posted January 30, 2015 I'm a beginner with this, so please be gentle, but doesn't the cable length, condition and routing have a bit to do with signal rating? Maybe mess with that first to see if there are any gains? B Link to comment Share on other sites More sharing options...
ahardb0dy Posted January 31, 2015 Share Posted January 31, 2015 (edited) They usually recommend using 18' of coax but this is debated often, using the right coax is more important than the length, the right coax for a single antenna would be RG58 or RG8x ( which is better), for two antennas RG59/U would be used. Two antennas should not be installed on our trucks, they are designed for semi sized trucks and should be a minimum of 12' apart. The reason semi's run twin antennas is the reception pattern from twin antennas is better forward and backwards than side to side, most truckers are more concerned with what is going on ahead and behind them. than from the sides. If you have excess coax you should bundle it together in a coil no less than 12", tie wrap each end and tuck it out of the way. If the SWR's are high on all channels it may be from a lack of a good ground plane, this may occur if the antenna is mounted on a spare tire carrier among other area's that do not have a good ground connection to the body, a wire can be run from the mount to the frame to help in grounding the antenna. The 102" whips are designed to be installed with a spring. I prefer a base load coil antenna and use Wilson brand antennas (Wilson 1000), everyone has their favorite. I like the base load antennas as you only have a thin whip compared to a fiberglass or a metal whip, the thin whip will bend when it hits tree branches, etc. and is also removable when you don't need/want the whip installed ( Wilson gives you a cap with the antenna to cover the threaded mount) Magnet mount Wilson antennas work fine, I prefer the perm. mount but a hole would need to be drilled, ideal location is in the center of the roof, this gives a unidirectional pattern. An antenna is directional to the opposite directions that it is mounted, for example an antenna on the pass/ rear is more directional to the front left.. You can have the best CB and a crap antenna and you will not get out or receive well, but a good antenna will make a crap CB work just fine. Where did you check your SWR's? You should be in an open parking lot or similar area with no over head wires, doors of the truck closed. When you key the mic and the swr reading is high, are you parked or moving? What meter are you using to check the SWR? I would also check the ends of the coax cable, what brand of cable are you using? If from Radio Shack I would recommend checking in a truck shop or a CB store if there is one around and try to find the grey RG8X cable, much better than the Radio Shack coax which they usually just crimp the ends on too. Edited January 31, 2015 by ahardb0dy 1 Link to comment Share on other sites More sharing options...
Precise1 Posted January 31, 2015 Share Posted January 31, 2015 Thanks for the information, I only knew about 1/2 of that. So I might have been on to something... B Link to comment Share on other sites More sharing options...
vagabond Posted January 31, 2015 Share Posted January 31, 2015 (edited) They usually recommend using 18' of coax but this is debated often, using the right coax is more important than the length, the right coax for a single antenna would be RG58 or RG8x ( which is better), for two antennas RG59/U would be used. Two antennas should not be installed on our trucks, they are designed for semi sized trucks and should be a minimum of 12' apart. The reason semi's run twin antennas is the reception pattern from twin antennas is better forward and backwards than side to side, most truckers are more concerned with what is going on ahead and behind them. than from the sides. If you have excess coax you should bundle it together in a coil no less than 12", tie wrap each end and tuck it out of the way. If the SWR's are high on all channels it may be from a lack of a good ground plane, this may occur if the antenna is mounted on a spare tire carrier among other area's that do not have a good ground connection to the body, a wire can be run from the mount to the frame to help in grounding the antenna. The 102" whips are designed to be installed with a spring. I prefer a base load coil antenna and use Wilson brand antennas (Wilson 1000), everyone has their favorite. I like the base load antennas as you only have a thin whip compared to a fiberglass or a metal whip, the thin whip will bend when it hits tree branches, etc. and is also removable when you don't need/want the whip installed ( Wilson gives you a cap with the antenna to cover the threaded mount) Magnet mount Wilson antennas work fine, I prefer the perm. mount but a hole would need to be drilled, ideal location is in the center of the roof, this gives a unidirectional pattern. An antenna is directional to the opposite directions that it is mounted, for example an antenna on the pass/ rear is more directional to the front left.. You can have the best CB and a crap antenna and you will not get out or receive well, but a good antenna will make a crap CB work just fine. Where did you check your SWR's? You should be in an open parking lot or similar area with no over head wires, doors of the truck closed. When you key the mic and the swr reading is high, are you parked or moving? What meter are you using to check the SWR? I would also check the ends of the coax cable, what brand of cable are you using? If from Radio Shack I would recommend checking in a truck shop or a CB store if there is one around and try to find the grey RG8X cable, much better than the Radio Shack coax which they usually just crimp the ends on too. I'll have to agree with almost all of that except for the dual antennas or as we called them co-phased I was running 108 fiberglass whips on my wife's ford maverick and the match was 1.2 to 1 with the Palomar off, with it on the match went up a little but the 60 watts sure made it talk. Roof mounts we would drill the hole above the dome light and run the coax between the roof and headliner. On my pathy I'm using a mirror mount on the spare tire carrier and a 4 ft firestick they're easy to tune if you know what to do Edited January 31, 2015 by vagabond Link to comment Share on other sites More sharing options...
ahardb0dy Posted January 31, 2015 Share Posted January 31, 2015 I never said you wouldn't get a good SWR reading running co phased antenna's on a small vehicle, I just was saying it effects the reception/transmitting pattern. 108" whips on a Maverick? front and rear I hope? On my old hardbody I drilled the hole right in the center of the roof (king cab), was easy to get to the cable inside after removing the sunroof latch and rubber trim. I guess on some vehicles with tire carriers there can be a problem depending on how the carrier mounts are isolated from the body, and some vehicles use bushings ( not metal). I used to run firestick fiberglass whips, I prefer the one's that you remove the rubber cap and can adjust them with an allen wrench. Link to comment Share on other sites More sharing options...
ahardb0dy Posted January 31, 2015 Share Posted January 31, 2015 This is the Wilson I prefer, roof mount, permanent mount ( have to drill a hole): http://www.wilsonantenna.com/products/cb-antennas-kitswhips-tips/sp/wilson-w1000-series-roof-top-mount-mobile-cb-antenna-kit/ Link to comment Share on other sites More sharing options...
vagabond Posted February 1, 2015 Share Posted February 1, 2015 nope they were both on the back bumper, it was kind of a popular set up back in the early 70s, at least in socal Link to comment Share on other sites More sharing options...
vagabond Posted February 1, 2015 Share Posted February 1, 2015 I I used to run firestick fiberglass whips, I prefer the one's that you remove the rubber cap and can adjust them with an allen wrench. yeah that's a lot easier then trimming the coil on the antenna Link to comment Share on other sites More sharing options...
ahardb0dy Posted February 1, 2015 Share Posted February 1, 2015 actually Wilson fiberglass whips use the set screw to hold the short metal adjustment part on the end, Firestick (the easily adjustable models) use a sort of nut and the adjustable part screws up or down. two antenna's on the rear would make for some good range facing forward I'm sure ! Link to comment Share on other sites More sharing options...
TheFatMacgyver Posted February 1, 2015 Author Share Posted February 1, 2015 Thanks ahardbody for that really good information. I think everyone in here has learned something new, at least I have. Link to comment Share on other sites More sharing options...
ahardb0dy Posted February 2, 2015 Share Posted February 2, 2015 Welcome Link to comment Share on other sites More sharing options...
ThaBigPerm Posted February 3, 2015 Share Posted February 3, 2015 I will add that it's generally not a good idea to coil excess coax cable, as that creates, well, a coil, which is also called an RF choke and can cause problems. Best to run excess cable in a back-and-forth loose skein or hank than a coil. Link to comment Share on other sites More sharing options...
ahardb0dy Posted February 4, 2015 Share Posted February 4, 2015 I didn't mean to make it sound like a coil, I usually will bunch the coax together in a loop about 12-14" long and tie wrap the ends, If I have that much extra. Link to comment Share on other sites More sharing options...
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