Technics RS-B555

Mi
SCHEMATIC
DIAGRAM
(Parts list on pages 34, 35, 42~44.)
(This schematic diagram may be modified at any time with
development of new technology.)
Notes:
¢ S701 : Stop switch (stop) in “off” position.
¢S702 : F.F. switch (ff) in “off” position.
¢ $703 : Rew switch (rew) in “off” position.
e S704 : Playback switch (Play) in “off” position.
eS705 : Record switch (rec) in “off” position.
¢S706 : Pause switch (pause) in “off” position.
© $707 ; Dolby noise-reduction switch (Dolby NRC) in “off” position.
¢ $708 : Dolby noise-reduction switch (Dolby NR B) in “off” position.
¢S709 : Multiplex filter switch (MPX filter) in “off” position.
¢S710 : Timer switch (timer) in “off” position.
¢S711 : Counter reset switch (counter reset) in “off” position.
e$713 : Meter range switch (meter range) in “off” position.
¢S714 : Memory mode switch (memory repeat) in “off” position.
¢S715 : Memory mode switch (memory stop) in “off” position.
¢S716 : APRS switch (APRS) in “off” position.
¢S717 : Automatic-record-muting switch (auto rec mute) in “off”
position.
¢ S718 : Power switch (standby © /on) in “on” position.
© $971 : Mode switch in “off” position.
e $972 : Cassette half detection switch in “off” position.
¢$973 : ATS (CrO,) switch in “off” position.
© $975 : Rec Inhibit switch in “off” position.
© S976 : ATS (Metal) switch in “off” position.
e Resistance are in ohms (Q), 1/4 watt unless specified
otherwise.
1K=1,000 (Q), 1M=1,000k (Q)
¢ Capacity are in micro-farads (uF) unless specified otherwise.
¢ All voltage values shown in circuitry are under no signal
condition and playback mode with volume control at minimum
position otherwise specified.
an ecrererecree Voltage values at record mode.
For measurement us EVM.
¢ Important 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.
°( —ume< +B >eemme ) indicates +B (bias).
°( seem-B8>seeem ) indicates —B (bias).
) indicates the flow of the playback signal.
o( as ) indicates the flow of the record 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.
* Put a conductive mat on the work table.
* Do not touch the legs of IC or LSI with the fingers directly.
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