Technics RS-CH7 - Page 13

RS-CH7 RS-CH7 ;
|_| SCHEMATIC DIAGRAM (Parts list on pages 25 ~ 28.)
Notes:
S810 : Counter reset switch in “OFF” position. (COUNTER RESET)
eS811 : Stop switch in “OFF” position. (STOP)
©S812, 813 : FF/REW/MS switch. (S812: BP, S813: <<)
0S814, 815 : Playback switch. (S814: B®, S815: <)
0S816 : Rec pause switch. (REC PAUSE)
©S817 : DECK 1/DECK 2 selector switch. A
eS818 : Synchro start switch. (SYNCHRO START)
eS819 : Edit speed switch. (SPEED)
©S820 : Dolby NR switch in “OFF” position.
S821 : Reverse mode switch. (REVERSE MODE)
eS971A~976A : DECK 2 mechanism leaf switch.
S971A: Mode detect.
S972A: Half detect.
S973A: Reverse side record prevention tab detect.
S974A: Forward side record prevention tab detect.
S975A: ATS (CrO2).
S976A: ATS (Metal).
°S971~973 : Deck 1 mechanism leaf switch. B
S971: Mode detect.
$972: Half detect.
$973: ATS (CrOz).
®|Indicated voltage values are the standard values for the unit measured by the DC electronic circuit tester (high-impedance) with the
chassis taken as standard.
Therefore, there may exist some errors in the voltage values, depending on the internal impedance of the DC circuit tester.
No mark...Playback (__ )...Recording
e|mportant safety notice:
Components identified by A\ mark have special characteristics important for safety.
When replacing any of these components, use only manufacturer’s specified parts. Cc
eThis schematic diagram may be modified at any time with the development of new technology.
meaummn : Negative voltage line
a : Recording signal line
wummmmes © Positive voltage line
E > : Playback signal
Caution!
IC and LSI are sensitive to static electricity.
Secondary trouble can be prevented by taking care during repair.
Cover the parts boxes made of plastics with aluminum foil. :
Ground the soldering iron. D
Put a conductive mat on the word table.
Do not touch the legs of IC or LSI with the fingers directly.
eThe supply part number is described alone in the replacement parts list.
| RefNo. Production Part No. Supply Part No.
IC3, 5, 7 BA4558FT1 SVIBA4558F
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