JVC TH-S77 Service Manual page 21

5.FORCED NTSC MODE
It is made compulsive NTSC mode.
From this, with regards to the input of NTSEL_SW, there is nothing only
at the time of 1st power on, and it performs NTSC starting.
(Command specification is performed to a module.)
A mode clearance is performed by power off.
VIDEO FORMAT change is prohibited during Forced NTSC mode.
Insert the power cord in an outlet while
pressing the "POWER" and "PAUSE" keys
on the main unit simultaneously.
A main unit entered in the
NTSC mode compulsively.
6.TRAY LOCK
A loader mechanism's tray lock is carried out. In the tray lock function ON state,
EJECT processing is not performed to the EJECT key.
And , a LOCK display is performed at this time.
When it turns off a tray lock function, STOP and EJECT KEY are pushed simultaneously again.
Back up ON/OFF of a tray lock.
Press the "STOP" and "OPEN/CLOSE1" keys
on the remote controller at standby.
A tray lock is completed.
7.TUNER AM 9k STEP SW (only U version)
AM frequency is changed with 9k STEP.
Press the "STOP" and "PLAY" keys on
the main unit simultaneously.
A tuner unit entered in the
9k step mode.
8.TUNER AM 10k STEP SW (only U version)
AM frequency is changed with 10k STEP.
Press the "STOP" and "PAUSE" keys on
the main unit simultaneously.
A tuner unit entered in the
10k step mode.
(No.MB421)1-21