Fluttering w/squelch Cobra 29 ltd 2007 year
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perrym1962
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- Location: East View, Ky.
Fluttering w/squelch Cobra 29 ltd 2007 year
I have a fairly new Cobra 29ltd chrome. When you turn up the squelch just enough for the noise to go away there is a fluttering sound in the receive. You can turn it on up more and it goes away, but a weaker signal will get cut out. I have had other newer 29's that did this as well.
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tireman247
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Fluttering w/squelch Cobra 29 ltd 2007 year
i did have the same problem as you and this was the fix, i found this info on this forum.
NightRanger3151,
I have experienced that same thing with my Cobra 29 LTD’s, it probably has done it on the few dozen or more I have worked on, they must be designed like that. The noise is strange, it is kind of a muffled up static that is heard through the radios speaker when the SQUELCH is just above its threshold, you can make the noise go away by cranking up the squelch control, however, weaker stations may not break it at such a high point, which is a drawback.
Here is what I have found to reduce or completely eliminate the noise from just experimenting: Solder a 0.1uf (it has 104 on the cap) or a 0.01uf (103) (the 104 works better) ceramic capacitor across the middle pin (collector) of TR12 & the other leg (base) of TR12 towards the front of the radio, I have tried it on newer & older 29’s and it eliminated the noise, & the squelch circuit & the rest of the radio still seemed to function normal. So you just solder a 0.1uf (104) ceramic capacitor to TR12’s collector (middle pin) & TR12’s base (pin towards the front of the radio). TR12 is part of the squelch circuit.
I hope this info helps, again this was just from me experimenting so it may not be the best method, but it works fine for me & does not seem to hurt performance of the radio in any way & the squelch circuit seemed to work more like it is suppose to. Take Care & again hope this helps. Pioneer621
NightRanger3151,
I have experienced that same thing with my Cobra 29 LTD’s, it probably has done it on the few dozen or more I have worked on, they must be designed like that. The noise is strange, it is kind of a muffled up static that is heard through the radios speaker when the SQUELCH is just above its threshold, you can make the noise go away by cranking up the squelch control, however, weaker stations may not break it at such a high point, which is a drawback.
Here is what I have found to reduce or completely eliminate the noise from just experimenting: Solder a 0.1uf (it has 104 on the cap) or a 0.01uf (103) (the 104 works better) ceramic capacitor across the middle pin (collector) of TR12 & the other leg (base) of TR12 towards the front of the radio, I have tried it on newer & older 29’s and it eliminated the noise, & the squelch circuit & the rest of the radio still seemed to function normal. So you just solder a 0.1uf (104) ceramic capacitor to TR12’s collector (middle pin) & TR12’s base (pin towards the front of the radio). TR12 is part of the squelch circuit.
I hope this info helps, again this was just from me experimenting so it may not be the best method, but it works fine for me & does not seem to hurt performance of the radio in any way & the squelch circuit seemed to work more like it is suppose to. Take Care & again hope this helps. Pioneer621
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perrym1962
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- Joined: Monday 4th Sep 2006, 17:00
- Location: East View, Ky.
Fluttering w/squelch Cobra 29 ltd 2007 year
I appreciate your reply. I will try that this weekend, and let you know the outcome. Thanks, Perry in Ky..
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perrym1962
- Frequent Keyer
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- Joined: Monday 4th Sep 2006, 17:00
- Location: East View, Ky.
Fluttering w/squelch Cobra 29 ltd 2007 year
I didn't have a 104 so I came up with a 103. Took care of the problem. Again thanks for your time and solution. Works great. Perry....