antenna/swr frustration

what is an acceptable swr level? and what is your swr on 1 and on 40? Is your antenna grounded?

 

is it a magnet mount or is it a permanent mount, and does the bottom of the antenna have a little wire coming off?

 

Well, im not sure exactly how your antenna works, so it might work that way it might not, but you would have to attach the wire to somewhere you know is grounded... chassie, some bolt, anything grounded.

i may be setting up dual antennas, and i need to pick up another antenna, and the cable, so i may be going to a shop tomorrow, ill check out that antenna and ask how to ground it if need be.

 

you need a no ground antenna.Because of the fiberglass on the cab of your truck.If you keep the wilson attached you will have to ground it to your chassie somewhere.

 

Just in case the mount itself is installed incorrectly, it's worth a quick check with an ohmmeter. Remove the antenna but leave the mount and coax in place. Disconnect the coax connector from the rear of the radio. Put the meter on "ohms" and put one lead on the center pin of the plug and the other on the shell. The meter should not move, or show "Overflow" or Infinite or whatever it does when the two leads are not touching anything if it's a digital meter. If the meter moves to zero, you've got a short in either the coax or at the mount.
If, as we hope, the needle did not move, nor the display change when you touched the two parts of the plug, step two often calls for either being a contortionist or needing a second person. Touch one meter lead to the center pin on the plug (at the radio end) and the other lead to the center pin on the mount. NOW you should get a swing towards zero, or a very, very low resistance (like no more than 1 ohm). That tells you that the coax isn't broken, and is attached to the right part of the mount. Thirdly, have your helped touch his probe to the outer shell of the coax plug, and you touch the truck part that the mount is bracketed onto. Again, you should get close to zero ohms. If the needle doesn't move when you do this, your mount point isn't grounded.
Those three little tests should be able to tell you that the feedline and mount are OK, and your most likely need is, as mentioned above, either a better RF ground, or a "no-ground-plane" antenna, similar to those used on small boats.
Hope this helps,
-- Handlebar --
diddly dahdidah

 

Never have seen one that worked with a darn!! To the OP, run some braided ground straps in short runs, 2ft or less, from the antenna bracket to the frame. Make sure your antenna is mounted properly as handlebar stated. I used to drive a century, you can get a good SWR reading, good being 1.5:1 or less, with just a little effort. Remember, your antenna needs to be out in the open as far as possible, i.e. move it out on the mirror support arm as far as possible from the body and stacks. Don't lean it forward more than about 15 degrees for maximum performance (it is a vertical antenna).

 

Only the silver load has the wire mentioned, not applicable in your case. No reason to make things overly complicated. Run a braid strap or 8 Ga wire, or even a length of mini 8 (about 18 inches) using the shield braid as your conductor from one of the 4 bracket bolts to one of the two Tor-X bolts that bolts the mirror to the door. Solder a 1/4" and 3/8" ring terminal at each end of your ground strap after measuring it for length. Most often this will be adequate ground. Connect no wires to the antenna. Nothing but the coax at the hardware bottom with the antenna on top, in other words normally. Also your stinger is too long, remove 1 inch from the bottom to start and go from there. If you are starting with a fresh 66 inch stock Wilson stinger it may be from 2 to 4 inches too long assuming your shaft is not longer than 18 inches. Since it is easier to remove than put back carefully measure between each cut taking no more than 1/4 inch at a time since you are using a radio and meter to make your measurements. I tend to be more caviler in cutting from years of experience combined with an analyzer which allows me to begin knowing where the resonant dip is and how much length corresponds to frequency. Better if you play it safer, you may only want to remove 1/2 inch to start since you do not really know where you are to begin with. Judging from your setup and stated readings I have no doubt you are still an inch and a half too long minimum combined with your grounding problem. Do as Mike mentioned let the coil see sky as much as possible while being as far as possible away from any part of the truck.

In short your stinger is too long and your ground is inadequate. I should add if you get a reasonable dip but still a little high like say 1.8:1 or so after tuning then you may wish to add a couple short flat braid straps inside the door hinge area from the door to the body across the hinge, to get the overall door to body ground better. Seldom is this needed unless the truck is a few years old. Remove a bolt on each side and shiny the metal before bolting the short (3 or 4 inch) length of strap across the hinge from door to body. I prefer doing this at top and bottom when I see it is needed. Usually by the time this step is needed one should also crawl around under the truck inspecting any ground straps from body to chassis across the bellows shock absorber(s). Typically when these corrode out you begin hearing noise (in your receiver) which alters when using the clutch or brake.