Panasonic KX-TG6051BXM Service Manual page 18

KX-TG6051BXM/KX-TGA601BXM
4.5.6. Auto Disconnect Circuit
Function:
This circuit is used to detect the fact that another telephone connected to the same line is OFF-HOOK while the unit is in a
receiving status or OGM transmitting status.
Circuit Operation:
The voltage of pin 90 of IC501 is monitored. If a parallel-connected telephone is put into OFF HOOK status, the presence/
absence of a parallel connection is determined when the voltage changes by 0.2 V or more. When the set detects the parallel-
connected telephone is OFF HOOK status, the line is disconnected.
You can enable or disable the Auto Disconnect function.
See Check Record (P.56)
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