High SWR... Low SWR

[1 ADAM 12]

I have a brand new Cobra 29 that I recently installed in a family member's vehicle. Brand new radio, brand new 2ft Firestik antenna, brand new RG8X coax. I checked and adjusted the SWR to a 1.5:1 on channel 1 and 1.6:1 on channel 40. Afterwards I put the coax back in-line between the radio and antenna. On channels 1-29 the radio operates correctly. On channels 30-40 the "antenna light" comes on indicating a high SWR. What gives? Is the SWR meter lying to me or is the antenna light coming on needlessly? Thanks for the help.

[Cobra CHROME]

If u adjusted ur SWR with a good external meter then ur probably OK...u said u had a 1.6 swr and if ur swr light is set to come on at 1.5 then that's what's happening. Radios are suppose to be set to come on at certain swr levels. On a peaked cobra 29 its not uncommon for it to blink while talking.

Check jumpers if u have any. Check the swr on ur radio as well as external meter. Once both are good then I wouldn't worry about the light. Most of the swr lights are adjustable.so if u peaked the radio it may be causing it to come on.

If in doubt, take it to a shop.

[1 ADAM 12]

Thank you for the reply. The radio has not been peaked or tuned yet. I was not aware that there were set levels for the SWR light to engage. The light does blink on channel 30 while talking. It makes a lot more sense now. This radio is being operated barefoot. I will have the light adjusted just for the sake of safety and my excessive compulsive...Thanks again

[sonoma]

Thank you for the reply. The radio has not been peaked or tuned yet. I was not aware that there were set levels for the SWR light to engage. The light does blink on channel 30 while talking. It makes a lot more sense now. This radio is being operated barefoot. I will have the light adjusted just for the sake of safety and my excessive compulsive...Thanks again

here is the bulletin from cobra on radios that the light comes on below 3 swr rating. tells you how to adjust it.

[Please login or register to view this link]

[1 ADAM 12]

Thanks for the link Sonoma. I printed it out and will get that adjusted.

[Nodoz]

Here is a link to a chart I found interesting pertaining to swr and the loss of power as the swr increases. The chart is based on 4 watts of output.

[Please login or register to view this link]

[sonoma]

Thanks for the link Sonoma. I printed it out and will get that adjusted.

that is a service bulletin put out by cobra. they found out they had a problem from the factory being out of adjustment a few years ago