Cobra18 WXSTII No modulation

[Critter98]

I just picked up this radio. Everything works but no modulation. Throws a strong carrier. Weather channels come in good, squelch works & scans fine. I've tried another mic, it is not the antenna, running off a pwr supply that works on several other radios. Everything external checks out. Internally nothing is burnt, soldering looks fine, nice cone shaped & shiny. Does anyone have any experience with this radio or suggestions what I can try? Tks in adv.

 

[ForestRunner98]

Have you tried turning VR2? That’s the modulation adjustment.


The blue colored do-hickey, thing-a-ma-bob.

 

[nomadradio]

Is the other mike working on another radio? Two bad mikes sounds unlikely, but mikes break more often than radios. If the spare mike you tried is untested, that still leaves open this possibility.

73

 

[Critter98]

Have you tried turning VR2? That’s the modulation adjustment.

View attachment 68614
The blue colored do-hickey, thing-a-ma-bob.

Have you tried turning VR2? That’s the modulation adjustment.

View attachment 68614
The blue colored do-hickey, thing-a-ma-bob.

Yes I tried this, but it did not do anything.

 

[Critter98]

Is the other mike working on another radio? Two bad mikes sounds unlikely, but mikes break more often than radios. If the spare mike you tried is untested, that still leaves open this possibility.

73

The second mic did exactly the same thing as the original mic. I tested both mics and they are wired correctly.

 

[Shadetree Mechanic]

I have an older version of this radio, and it has an electret condenser mic from the factory. Do you have the original mic for it?

 

[Shadetree Mechanic]

Try plugging a speaker into the PA and see if audio works? If so then maybe the mode selector switch needs to be cleaned?

Here is some info on this radio:

Cobra 18WX ST II

 

[Critter98]

I have an older version of this radio, and it has an electret condenser mic from the factory. Do you have the original mic for it?

Yes it is the original mic. I also have downloaded all the info for the radio. Thanks.