Antenna warning

Discussion in 'CB Radio Forum' started by Logan Spoo, Aug 6, 2018.

  1. Logan Spoo

    Logan Spoo Bobtail Member

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    I replaced my Wilson 2000 antenna 5” shaft with a new Wilson 2000 with 10” shaft and new coax cable I recalibrated and read swr with no cutting swr was 1.5 across the board. If I transmit on ch. 1-20 no antenna warning but ch 20-40 the red ant warning lights up. Is this just a case where I need to cut some? I’m on ch 40 90% of the time
     
  2. #wishfulthinking

    #wishfulthinking Light Load Member

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    What is your SWR reading on ch 40? What kind of radio is it? If it's a Cobra then it sounds like it's too high. If that's the case, you will need a trim. Before you do that though (If it has an SWR switch on the radio) make sure the SWR switch is in the right position and double check the SWR on ch 1, ch 20 & ch 40. I'm not insulting your intelligence here, it's just easy thing to overlook and it's been done many times before.
     
  3. Diesel Dave

    Diesel Dave Last Few of the OUTLAWS

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    When I replaced my short shaft to an 18” shaft, I didn’t replace the coil. I had to cut the stinger quite a bit to get the SWR back down. Mine is a 2000 also and has it more than 20 yrs, even longer.
     
  4. Logan Spoo

    Logan Spoo Bobtail Member

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    Yes it's a 29 Ltd a
    Classic. I will recheck swr and probably will trim some thanks for the advice guys!
     
  5. Diesel Dave

    Diesel Dave Last Few of the OUTLAWS

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    You have to use one of those antenna analyzers. The one on the radio isn’t good enough. I reliable radio shop should charge from 15-20 to get it on the money.
     
  6. Night Stalker10

    Night Stalker10 Road Train Member

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    I wouldn’t trim your antenna, until you get a good external meter on it, to see what the swr really is. I have been driving our companies t800 last week, and it has a brand new cobra 29 LX in it. Its fairly quiet at times. The internal meter in the radio shows SWR at 1.2. I brought my antenna analyzer from home and it showed a 5.1 for swr. Just shows you can’t trust the internal swr meter on those cobra radios. Also, those swr warning lights can be kind of flaky too.
     
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  7. Ridgeline

    Ridgeline Road Train Member

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    BEFORE you do a thing, get an external SWR meter and figure out what the SWR really is. If you can't go to a shop that can do it and tell you what is wrong.
     
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  8. Expeditor

    Expeditor Medium Load Member

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    Last edited: Aug 7, 2018
  9. Ridgeline

    Ridgeline Road Train Member

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    Yeah there is one but I doubt the OP has a 25 ohm resistor and a 1kc audio source to set it with.
     
  10. Expeditor

    Expeditor Medium Load Member

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    No audio source or resistor needed. Right from Cobra. Won't hurt the radio.