Sony GY-8240UWD Maintenance Manual page 243

Push up cassette window inside. Press switches in arrow direction.
SW3:
L cassette detection switch
[Cassette size sensor]
Rear
Front
Cassette in sensor (L) Cassette size sensor
GY-8240UWD
GY-8240FC
SW1:
Cassette in switch 1
[Cassette in sensor (L)]
Position of Cassette Compartment Switches
Top View of Cassette Compartment
SW2:
Cassette in switch 2
[Cassette in sensor (R)]
Cassette in sensor (R)
5-4. DIAG Mode
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