Technics ST-HD50 User Manual

| ST-HD50
m@ Schematic Diagram
Page
PD TINE CIRCUIT, siccccesec.cesseccstecat tie seeeteda cia asicciees lids atin ees eites 8,9
BEM CONNECTOR CIRCUIT cece actact icon gsis) ctaumietan ators ctactaaratesstaysicsuslewnaernialetey 5: 10
INPUT/OUTPUT CIRCUIT sssscossce.ccanthindncinsreernanasa mace amani tect 10
Bee MAIN CIRCUIT s ssccscenaiseieti oA antanttneeteneae 10~12
WR RE CUR GUIT costo sectet te terete te nctcpsi cee ernie en 13,14
OPERATION GCIRGUIN <ccscorsecpt cae aeeiee aeheeeeetcetsennins 14
® This schematic diagram may be modified at any time with the development of new technology.
Notes:
@ S901 : Record timer switch (© REC)
@ $902 : Play timer switch (® PLAY)
@ S903 : Clock/Timer switch (CLOCK/TIMER)
e@ $904 : Set switch (SET)
@ $905,906 : Tuning/Time adjust switch (TUNING/TIME ADJUST)
(S905: DOWN, S906: UP)
@ $907 : Tuning mode select switch (TUNING)
@ $908 : Source input select switch (INPUT SELECTOR)
@ S909 : FM band select switch (TUNER, FM)
@ $910 : AM band select switch (TUNER, AM)
®@ 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: Power ON
@ Voltage values and waveform are measured as indicated in the schematic diagram when test points between Bigs and MAaA0 ,
and between and , and between and are shoted.
No mark: FM MODE ( ): AM MODE
® important safety notice:
Components identified by A mark have special characteristics important for safety.
Furthermore, special parts which have purposes of fire-retardant (resistors), high-quality sound (capacitors), low-noise (resistors), elc. are
used. When replacing any of components, be sure to use only manufacturer's specified parts shown in the parts list.
®@ 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.
@ Voltage and signal line
mmampees © Positive voltage line ap : AM signal line mam - AM OSC signal line
sum peee - Negative voltage line [——> : FM signal line OOC> : AM OSC signal line
: REC OUT signal line

Technics ST-HD50 Specifications

General

Brand	Technics
Model	ST-HD50
Category	Tuner
Language	English