JVC TH-S3 Service Manual page 23

(5) Compulsive 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.
(6) TUNER AM 9k step SW (only U version)
AM frequency is changed with 9k STEP.
(7) TUNER AM 10k step SW (only U version)
AM frequency is changed with 9k STEP.
Insert the power cord in an outlet while
pressing the "STOP" and "F.SKIP" keys
on the main unit simultaneously.
A main unit entered in the
NTSC mode compulsively.
Press the "STOP" and "B.SKIP" keys on
the main unit simultaneously.
A tuner unit entered in the
9k step mode.
Press the "STOP" and "F.SKIP" keys on
the main unit simultaneously.
A tuner unit entered in the
10k step mode.
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