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Cobra 148 gtl ST

Discussion in 'General CB Services Discussion' started by Robalo, May 23, 2020 at 4:54 AM.

  1. Robalo

    Robalo Well-Known Member

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    On this audio circuit, what’s the best upgrade or mods you guys recommend? The audio on this radio is too low. Any help appreciated!


     

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  2. Robalo

    Robalo Well-Known Member

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    TP AND VR JUST ZOOM IN
     

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  3. ExitThirteen

    ExitThirteen Grumpy and Cranky

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    Change out R131 to a 15k ohm. On the original 148's, R131 was originally a 10k ohm, increasing the value would bring up your modulation on AM.


    Am I correct in assuming you have low AM modulation?



    ~Cheers~
     
  4. kopcicle

    kopcicle Sr. Member

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    seems right ...
     

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  5. Robalo

    Robalo Well-Known Member

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    thank you E-13 and Kopcicle This is cobra 148 gtl ST and it used on the audio power amp KIA 7217AP it burn out 2 IC so far the squelch been used for variable power out I am trying to put back every thing back to factory setting, waiting for the new IC to continue, the schematic I downloaded is similar and I mark with color some VR and TP for easy finding all you have to do is zoom all the way in and you will see the marks. I hope it comes as a help to anyone.
    73's ROBALO
     
  6. 9C1Driver

    9C1Driver Sr. Member

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    Ouch sounds like a basket case of a radio. And on top of that it's a soundtracker which were marginal at best. At least your not paying someone to do the work, hope you get it fixed up.
     
    Robalo likes this.
  7. Low_Boy

    Low_Boy Sr. Member

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    That is the fun part. Bringing them back from the dead.
     
    Dmans, Robalo and TM86 like this.

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