SOURCE: Cobra 148 GTL steady tone though speaker
try rerouting your coax cable and make sure it's long enough
SOURCE: Cobra 1000 GTL by Dynascan
This is a complicated modification. I have never done it to a 1000 GTL, but its done basically the same in all radio's.
I don't recommend doing it, especially since I am not 100% sure on how exactly to do it. I have never been in a 1000 gtl. If I had one in front of me I could tell you for sure how to do it.
If the reason for Variable power is a linear, just a swing kit in for the dead key you need, most likely 2 watts, and leave it.
Here is how to do a variable power mod. this is assuming the swing mod is done the same to this as a cobra 25/29 or uniden 68/76 etc.
If you would like to try it, here it is.
You get a TIP31 transistor, Radioshack has them.
Where you put the swing mod in the radio, which is a cap and a resistor, you put the TIP31 and cap. A 47uf cap works fine.
With the resistor facing you, and the tab in the back away, solder the cap to the transistor. the leg with the black stripe goes on the right most leg. then the other goes to the center leg of the transistor.
Solder a wire on the left most leg, long enough to reach the front of the radio. Now solder the 2 legs that don't have the wire on it, in the place where you would put the swing kit, with the black stripe on the cap facing the back of the radio usually.
Remove the wires from the RF gain and solder them together.
Now solder the wire from the transistor to the center tab.
Remove VR6 and solder a wire from the top tag of the RF gain to the top connection of VR6 that you removed.
Then connect a wire from the bottom tag to a ground point. The side of a tuning can works fine.
Take a piece of shrink tube and put it over the TIP31 so it does not ground against the heat sink, that would be bad.
This is done basically the same in all cb radio's.
SOURCE: I have a Cobra 148GTL with a 5 pin side mount mic.
sounds like a bad mic....At the 5 pin end u will see a small screw take out that screw and slide the pin cover back and you will see the 5 wires going to the pins my bet 1 or more of those ends are broken all you ned is re sod. them and all will be good .....I buy alot of broken mics and all i need do is fix the wires easy fix .....
SOURCE: cobra 29, no rx, no tx, pa dose not work, good
Not sure which model you have as there are at least 13 cobra 29's. I am using the LTD as an example. You say good mic? Is it made for this model? If it is good then I would have to say the final audio stage is not working. The TA72222AP is the IC that is the final audio amplifier. Check pin 1 of the TA72222AP ic for 12 volts. If 12 volts is present then replace the audio IC TA72222AP. If 12 volts is not present then you have power supply problems that are internal. The conclusion I have made is based on no rx audio, ( could have been the jack at the pa and ext spkr) but you say they don't work either, also no meter movement during modulation check (that does not need a spkr to make the meter move) so yes I'm 99.99% sure its the final audio stage is a bad. If your model is not the LTD then the IC could be different but still the same audio final is bad. Replace the part which should be fairly inexpensive. If it uses a metal heat sink be sure to apply heat sink grease when installing new part.
SOURCE: Cobra 148 GTL ST. No AM transmit audio. Carrier is
Could be TR41 or TR42. I would try TR41 first.
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