NO SWR FOR CALIBRATION; good or bad?

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Vinnyjk123
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NO SWR FOR CALIBRATION; good or bad?

Post by Vinnyjk123 »

Just hooked up my Cobra 29 classic with a Firestik II 5' antennae on the side of a tool box on my dodge dakota. SO, when attempting to calibrate and check for SWR, on channel 40, my built in swr meter does not move from 1, needle maybe moves 1/2 a millimeter. Then on channel 1, I get around 1.1 - 1.2 SWR... I did not make any adjustments, this was right off the bat. I can calibrate to the appropriate place. I have been recieving transmissions, but there is a lot of noise; went from battery positive and a chassis ground in frame. This got rid of alternator / engine whine. I was talking to someone about 2 miles away, but they could not hear me and i could not hear them very good either. Is this a problem orrrrrr? Please help. Thank you.
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Re: NO SWR FOR CALIBRATION; good or bad?

Post by dmilner »

with the antenna off to the side swr will not be correct.. also the wave patern will be way off , it will be focused in one direction. need to center the antenna on the truck for a good radiating patern.
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Re: NO SWR FOR CALIBRATION; good or bad?

Post by Vinnyjk123 »

So if antenna is mounted in the middle of the toolbox in between it and the window, would be better?
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Re: NO SWR FOR CALIBRATION; good or bad?

Post by MDYoungblood »

Hello Vinnyjk123,
Welcome to the forum.
Having the antenna mounted to the toolbox side wouldn't be a problem but the distance away from the cab would be, the closer to the cab the harder it is to tune. One thing with the setup is relying on the radio's SWR meter. I would read the Cobra's instructions on how to set and read the SWR meter, then you need 3 reference points, channel 1, 19 or 20, and channel 40. adjust the antenna to the lowest SWR on channel 19/20 then balance it out between 1 and 40.
Next is the radio, not sure if it's new, used, or modded, you didn't say, but talking a couple miles depending on your location might be about right.
As a new member I always ask if you could post an intro in the "Welcome to the Forum" topic, http://www.cbradiotalk.com/viewforum.php?f=89 , so others here can say "Hi", thanks.

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Re: NO SWR FOR CALIBRATION; good or bad?

Post by Vinnyjk123 »

Thanks for the reply young blood. So now my question to you is, moving antenna to rear side of tooo box make a difference? In the place it is the SWR meter gives same readings no matter how I adjust antenna. It moves for calibration and when I key up the mic it is fine for that. I will post a pic where it is currently located

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Re: NO SWR FOR CALIBRATION; good or bad?

Post by MDYoungblood »

If you are making adjustments to the antenna and the meter isn't showing any difference than there is something else wrong. Check the coax with a multi-meter set on ohms and see if there is a short, remove the antenna first, touch the center pin and the outer edge of the connector, should read open. Good grounding is important too. Check the toolbox to see if it's got a good connection to the bed and the bed to the frame. You can find a lot about bonding in the forum, just use the search feature.

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Re: NO SWR FOR CALIBRATION; good or bad?

Post by Vinnyjk123 »

I performed all the testing of the coax cable, the antenna mount and the ground; all is good. Tool box is not grounded, but mount is grounded. I was just moving antenna with mount to different places on truck to see if SWR's would change but do not. on 1 does not move; 40 moves a little. Will be getting an external SWR meter tomorrow to ensure my readings are correct.
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Re: NO SWR FOR CALIBRATION; good or bad?

Post by MDYoungblood »

Is this antenna a magnet mount? I wouldn't want you to be drilling holes all over your toolbox. It would be best to ground the toolbox to the bed.

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Re: NO SWR FOR CALIBRATION; good or bad?

Post by sonoma »

have been following this post and am wondering what the dead key is for your radio?
if it has a dead key of 1 to 2 watts the swr meter will not work as it should.
here is how you check for SWR.
put the radio switch in the calibrate mode. key the radio and adjust the meter so the needle goes to the far right calibration mark. then turn the switch to the swr mode. key the radio and it will show the swr on the meter. since you keep saying it only goes to about 1 makes me think you are not checking this right. a radio that only keys 1 to 2 watts in most cases will not make the meter go over to the calibrate mark when trying to check SWR.
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Re: NO SWR FOR CALIBRATION; good or bad?

Post by Vinnyjk123 »

I have been doing it correctly as you explained, and this is what is happening. & my mount is grounded to the bed via a 4 in. 10 AWG wire with ring terminals. Mounting to center of tool box lid? Better or worse? Then ground tool box. Thank you.
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Re: NO SWR FOR CALIBRATION; good or bad?

Post by MDYoungblood »

When most say they mounted the antenna on their toolbox usually I think it is a mirror mount without the back plate, what mount are you using? Second where is this terminal lug on the mount connected?

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Re: NO SWR FOR CALIBRATION; good or bad?

Post by Vinnyjk123 »

I used a stake hole mount kit from fire stik drilled and screwed to the drivers side of the underside of the tool box with the ground wire from the mount to the bed rail.

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