Onkyo TX-7900 Service Manual

Ref. No. 3420
QUARTZ SYNTHESIZED
TUNER AMPLIFIER
MODEL TX-7900
MODEL TX-7920
Black and Silver models
SAFETY-RELATED COMPONENT WARNING! !
COMPONENTS IDENTIFIED BY MARK A ON
THE SCHEMATIC DIAGRAM AND IN THE PARTS
LIST ARE CRITICAL FOR RISK OF FIRE AND
ELECTRIC SHOCK. REPLACE THESE COMPO-
NENTS WITH ONKYO PARTS WHOSE PART
NUMBERS APPEAR AS SHOWN IN THIS
MANUAL.
MAKE LEAKAGE-CURRENT OR RESISTANCE
MEASUREMENTS TO DETERMINE THAT EXPOSED
PARTS ARE ACCEPTABLY INSULATED FROM
THE SUPPLY CIRCUIT BEFORE RETURNING
THE APPLIANCE TO THE CUSTOMER.
ONKYO
AUDIO COMPONENTS
TABLE OF CONTENTS
Specifications eee errr ee eee eee eee ee eee Tee eee eee eee ere Terre ree eee ere 2
Service procedures::+++i+sssssssstssesesesseeesseeseseeseserseeageeens 3
Exploded view Model TX-7920++:+++:+++s+sssesseseseeeeseeessseeneens 4
Parts Ist Model TX-7920 tse: wvesncwses ceracmmamninsaeennenee 5
Exploded view Model TX-7900++++++++++:ssess+sessesesseeereeesaeeens 6
Parts list Model 'TX-7900 issssster<eomnns sane venwavanes senna canon cones 7
Block diagram Model TX-7920-++++1:+++ssessseerseeesseersese seeeees 8
Block diagram Model TX-7900-+++++:++1s+sessseerseseseeteseeeeeeeens 9
IC block diagram and descriptions::::::1++++sseeeseseeseeseerees 10
Packing view svrcessscessceeeseeessseeseessenseneeseesesescnesensereanneens 17
Adjustment procedures ree eee eee eee er errr) 18
Printed circuit board view from bottom side-+r+++++rrr + est+* 21
Schematic diagram
Model "P7920: sere: ose cwaes uedewvensaes eonnenamenaee eemaseeeninenl 23
Model TX: 7900» «sss sentecnnsaxonenen nonce dvtineanennasaerawargicaeenines 25
Printed circuit board-parts list
Model "TX. 7620 se2nesenses ary deanwians sccswansapanvagis narangianane gies sen 29
Model 1X. 20 0Gxrtceswens corweswaieaee dennwonatennigipien vpeiciirnay 9 tate wea 39
TX-7900/TX-7920