Panasonic KX-FLB758RU Service Manual page 190

KX-FLB758RU
7.9.8. REGIST SENSOR....."FAILED PICK UP"
The Sensor detects whether or not the recording paper is present so that printing can start.
When the recording paper is detected, the shelter plate let the sensor light passing through, the photo-transistor turns ON, and the
input signal of IC610-154 pin becomes a low level.
When there is no recording paper, the shelter plate closes the sensor light, the photo-transistor turns OFF, and the input signal of
IC610-154 pin becomes a high level.
No Recording Paper
Recording Paper Regist
Photo-transistor Signal (IC610-154 pin)
OFF
ON
190
High level
Low level