Cobra 29ltd CLassic, TX power and audio is ok, volume from spkr is good, squelch works but no cb recieve.

You blew a diode near back of radio.(1) Take back cover off.spkr side) (2), see if you spot a black diode with a white stripe in right hand side between audio transformer and chassis near power wires coming in. (3)replace that diode; solder it..it may work again.

Begin with

• Volume knob 12 o'clock position
• Squelch knob full counter clockwise
• RF gain knob full clockwise
• Pa/CB switch to CB
• Mic plugged in
• Check coax and antenna connections.

• Make sure your antenna gommet/insulator is installed correctly or it will directed gound. Treat antenna shaft as it is the positive portion of circuit.

If you have another CB check the antenna system with that rig. To verify it is a radio issue. Then dig deeper Microphone, PLL chip, Audio chip etc.

Did you have someone get on channel 2 to see??? Maybe channel 2 was quiet and channel one had better receive or noise.. You never know until you check it with another radio. That is NOT a common issue at all on those radios. Better off doing that test.
"WILDCAT" IN LAURELVILLE OHIO
35 YEARS OF CB FUN!!!

Do you have talkback installed? It my be too loud and causing feed back. Back the mic gain down if so.

Could also be improper mic wiring. If you use a mic that is wired for a different radio, it could just cause a hum, buzz or squeal.

Another thing that can cause a hum, buzz or squeal is a faulty volume and or squelch knob depending on the radio.

• Turn down or disable talk back.
• If you cannot turn off or disable talk back, lower mic gain.
• Try a different mic that you know is wired for cobra.
• Play with volume and squelch knobs while TX and see if it stops at all. If it does replace knob.
  

There are some different things you could be facing like:
the speaker sound being cut-out by the mic switch, but my first guess is the switch in the external spkr. jack being faulty. Here is a schematic for you.

http://xbones_antennas.tripod.com/id21.html

Hi and welcome to FixYa,

Initially, the speaker of course has been checked?

Offhand, would partial schematic of the mic and speaker section help?



Good luck and thank you for asking FixYa.

Hello there
here is a link for the scematic ok?
best regards michael

1. Cobra 29LTD ST, 29WX ST 29LTD ST Owners Manual. 29WX ST Owners Manual. DIAGRAMS. 29LTD ST Schematic Diagram ... WX Schematic Diagram. 29LTD, 29LTD ST, 29WX ST Factory Service Manual ...www.cbtricks.com/radios/cobra/29ltd_29ltd_st_29wx_st/index.htm - Cached

You have antenna or Coax Problems...

Hi and welcome to FixYa,

Initially, pls a couple of ideas you may want to consider/explore or try/check:

• PA/CB switch must be to CB;
• RF Gain max clockwise;
• Squelch counter clockwise;
• Volume to your desired level;
• Mute (off);
• external speaker/speaker connection;
• audio amp, verify if there is TX modulation;
• antenna, antenna cable. SWR should be low.

Good luck and Thank you for using FixYa. Happy New Year.

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Check your speaker for a short.