K-40 Help

[wrong way]

Hello I have a bit of a challenge for work tomorrow a buddy of mine at work just put a Cobra 200 in his dump truck with a k-40 antenna (like 3ft with adjustable stinger on the end) swr was ok with his 949 but with the cobra his Radio Shack meter is showing like 1.2:1 on ch1, 1.7:1 on ch20 and like 3.5:1 on ch40 which leads me to believe it needs to be shorter. I havent had the chance to look at this yet but would like to be armed with your knowledge when I do. He said when he leans the antenna foward theese are the best readings he can get. (I figured that it was getting some reflect off the metal dump bed). straight up is just awfull I guess. I think that the radio shack meter swr part cant handle the DK that radio has I asked him What the meter said the DK was and he said 100watts WOW (that might be a problem in it's self I dont know) but also on the radio the antenna light comes on when he talks loudly so there must be a problem right? Any input would be greatly appreciated Thanks Wrong Way

[wrong way]

BTW it is mirror mounted on the left side of a Kenworth dump truck

[bam bam]

Ok from what I have read and been taught so far is that if the swr is higher on channel 40 than channel 1 then the antenna need to be shorten. If it higher on 1 than it's on 40 it needs to be longer. I think I think (subject to being wrong) but on the cobra if the antenna light comes on and it's properly ground or getting a good ground then the swr's being out of whack will cause the antenna light to come on!

['Doc]

I think from the SWR quoted that you're probably right, the antenna might be slightly too long. That 'tilting' of the antenna can have some affect on that, but doesn't change the fact that the antenna needs to be adjusted.
If that SWR 'light' comes on it means something just ain't right somewhere. Typically that's with the antenna, but not necessarily always so, especially if the radio has been modified in some way. I wouldn't blame things on the Radio Shack meter right off the bat. Certainly possible, but not too likely if the meter is being used correctly. (Radio Shack stuff always get a bad rap, even when there's nothing wrong with it, right?)
Have fun and good luck.
- 'Doc