Question about Cobra 148 GTL 120-Channels Base CB Radio

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Cobra 148gtldx low vol squelch on fm

Every thing else is fine just radio vol, even turned up squelch noise is low, it shouldnt be like this on fm, on running it for a day or two people sound ok so its really low vol on squelch, radio came from a mate who likes to mess in side, could be hes turned something, any ideas thanks marcbunn@googlemail.com ( late 80s early 90s cobra 148gtldx uniden board radio mk2 has eprom fm 145106 pll)

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  • 1205 Jun 23, 2008

    thanks very much problem solved had to replace 5 capcitors untill i got the right one, cost pennies as i have loads & a hour of my time thanks again marc.

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Hi Mate, the problem you are having in not uncommon in the
COBERA 148 GTL. I suspect that the problem lies in low value uF electro caps drying out (electrolite) causing power down and frequency drift. The capacitors are in two forms..tiny blue tantalum, and standard radial base caps that are grey aluminium
cans with a black stripe,it would be a job for a skilled person in electronics to replace all of them. The square metal cans with a screw ferrite slug are what you use to tune the radio, and as there are lot of them ,and you don't have a circuit diagram ,it would be pot luck finding the right one/s. What you realy need to know is all electronic devices age and hence, no longer do their job.
it would cost more than the set is worth to rebuild it,but if you have the skills ,it can be done. am cb with usb / lsb are a thing of the past now and you would be better off buying a used set that is still in top working order. The uhf sets are useless as was the am sets depending on what you want the sets to do, in convoy.... great....in remote country....useless. Having said that the am/usb/lsb sets are the best of the three because on ssb they tx on about 12 watts rms so you have a better chance of making contact, but don't count on it as hf cb is no longer in
common use.
GOOD LUCK flyingfox@people.net.au

Posted on Jun 23, 2008

  • flyingfox Jun 23, 2008

    Cheers Marc,well done!!...Perhaps you could post here the cap # of those you have replaced. This information may well help others as this is a common problem in the Cobra 148 gtl.

    flyingfox@people.net.au

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