A TELEPHONE WITH SENDING TONES

摘要

The circuit includes a microprocessor (1) for transmitting low or high state data through lines (L1,L2), a first power supply (2) for providing power supplied from telephone lines to the system, a detector (3) for detecting the long distance call outgoint control data, a false operation protector (4) for protecting the false operation of the detector, a second power supply (5) for providing power according to the output signal of the false operation protector (4), an on-off time adjuster (5) for detecting the on-off state of the power provided by the second power supply, and n oscillator (7) for generating oscillator signal in the case of on-state of the second power.