Dual function timer (CB20363E)

This circuit was found in 80's telecom documentation. Its purpose is to control a microphone in the process of transmitting voice and Morse signals.

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10 LEDs sequential (CB17096E)
What differentiates this circuit from the many versions with the 4017, presented in our...
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We found this circuit in the 1994 National Semiconductor Linear Applications Handbook. The circuit...
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