EXTERNAL TONE SQUELCH

Transmitters and Receivers Glossary

Transmitters and Receivers — External Tone Squelch

 

 

 

 

 

 

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Information on External Tone Squelch

If the control in noise squelch is not properly set, weak signals are not heard. In external-tone squelch, an inaudible 150-Hz tone is added to the audio signal before it is modulated onto the carrier in the transmitter. Before the AF stage in the receiver the presence of the tone is detected and used to activate a relay that turns the speaker on when the tone is present (that is, audio is present in the signal) or off when the tone is absent (that is, only noise is present).


Other topics in our resources on Transmitters and Receivers related to External Tone Squelch include: 
 
  • squelch
    		•
  • noise squelch
    		•
  • internal tone squelch

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