Technics SA-EH670 - Schematic Diagram Notes; Component Nomenclature and Safety Notes

IC451 (M38504E6255F)
RS-DV250:
IC701 (M38503M2406F)
Check these ICs and replace.
7.3.2. F61
- Problem or condition
When the power switch is switched on, it automatically switches
back off, making it impossible to switch power on.
- Correction procedure
Faulty Tuner/Amplifier (SA-EH670) output IC (IC601). (When a DC
voltage is applied to speaker terminals.)
8. Schematic Diagram Notes
- This schematic diagram may be modified at any time with the
development of new technology.
Notes:
S901:
Power standby/on switch ( /I)
S902:
Clock/timer switch (CLOCK/TIMER)
S903:
Demo switch ( DEMO)
S904:
Play timer/record timer switch / ( PLAY/ REC)
S905:
FM mode switch / (FM AUTO/MONO)
S906:
Tuning mode switch / (TUNING MODE)
S907:
Set switch (SET)
S908:
Source input switch / (INPUT SELECTOR)
S910:
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