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20.7. Line Sending Signal
The modulation signal input from the RF unit is demodulated by IC101 (BBIC), and the voice signal output from IC101-94 is
amplified at Q115 and Q107 to be output to the line circuit. When Q212 is turned ON by IC201-20, the transmitting voice signal is
muted.
amplified at Q115 and Q107 to be output to the line circuit. When Q212 is turned ON by IC201-20, the transmitting voice signal is
muted.
20.8. Line Receiving Signal
The voice signal from Q110 is amplified at Q103 and Q116, then led to pin 96 of IC101 (BBIC). Also the output from Q103 is
separated to be connected to the Caller ID circuit. IC101 modulates the input voice signal to output to RF unit. When Q204 is turned
ON by pin 19 of IC201, the receiving voice signal is muted.
separated to be connected to the Caller ID circuit. IC101 modulates the input voice signal to output to RF unit. When Q204 is turned
ON by pin 19 of IC201, the receiving voice signal is muted.
20.9. Power Down Detection Circuit
The power down detection circuit outputs the interrupt signal of active LOW to pin 34 of IC101 (BBIC) from Q114 when the power
supply voltage becomes lower and the output from pin 1 of IC106 is decreased from +5 V to +4 V.Receiving the interrupt signal,
IC101 (and IC201) quites the system when the power is down.
supply voltage becomes lower and the output from pin 1 of IC106 is decreased from +5 V to +4 V.Receiving the interrupt signal,
IC101 (and IC201) quites the system when the power is down.
20.10. ID Code Setting
When the Handset is placed on the base unit, new ID data is sent to the Handset through RF Unit.
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KX-TC1800B
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