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ST-SB920 SERVICE MANUAL AEP Model UK Model SPECIFICATIONS FM tuner section AM tuner section Frequency range 87.5 – 108.0 MHz Frequency range MW: 522 – 1,611 kHz (9 kHz step) 75 Ω, unbalanced Aerial terminals LW: 144 – 288 kHz (1 kHz step) Intermediate frequency 10.7 MHz...
MARK ! ON THE SCHEMATIC DIAGRAMS AND IN THE PARTS TEST MODE ·································································· 3 LIST ARE CRITICAL TO SAFE OPERATION. REPLACE THESE COMPONENTS WITH SONY PARTS WHOSE PART NUMBERS ELECTRICAL ADJUSTMENT ································· 5 APPEAR AS SHOWN IN THIS MANUAL OR IN SUPPLEMENTS PUBLISHED BY SONY.
SECTION 2 TEST MODE 1. Circuit Check Mode Set to the reception frequency that the curcuit can STEREO RDS stations. (Set the input level to above 70 dB.) This enables circuit check to be performed in any of the reception modes-FM, AM (MW, LW). Set to a desired band before setting the test mode.
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3. Entering the Factory Preset (In case perform just to write memory of the Factory Preset.) NOTE : As contents of the Factory Preset will be written into memory after completing this check mode, delete contents of memory according to 4. Forced RESET. 1.
SECTION 3 ELECTRICAL ADJUSTMENTS Precautions in Repairing FM Discriminator ADJUSTMENT (NULL and MONO Distortion Adjustment) If the front end unit fails, it is difficult to repair the inner circuits, so replace the entire front end unit. Setting: IF BAND : WIDE Set “IF : WIDE”...
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Stereo Level Adjustment Stereo Separation Adjustment Setting: Setting: IF BAND : WIDE IF BAND : WIDE ANT ATT : OFF FM RF SSG level meter FM RF SSG FM ANTENNA (75 Ω ) LINE OUT FM ANTENNA (75 Ω ) Modulation : Stereo Standard signal Output level : 6mV (76dB) (at 75 Ω...
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AM SECTION AM Meter Level Adjustment Setting: BAND : LW loop antenna loop antenna (Supplied accessories) AM RF SSG AM antenna 30% amplitude 60 cm terminal (TM1) modulation by 400 Hz signal Field strength dB ( µ V/m) =SSG output level dB ( µ V/m) –26 dB. Carrier frequency : 216kHz Modulation : AUDIO 400Hz, 30% modulation Procedure:...
THIS NOTE IS COMMON FOR PRINTED WIRING For printed wiring boards. Note: BOARDS AND SCHEMATIC DIAGRAMS. • X : parts extracted from the component side. (In addition to this, the necessary note is printed in • b : Pattern from the side which enables seeing. each block.) For schematic diagrams.
4-7. IC PIN FUNCTION (DISPLAY BOARD) • IC701 System Control (µPD780205GF-040-3BA) Pin No. Pin Name Function — Power supply (+5V). — Not used. (Open) — Not used. (Open) BAND1 — Not used. (Open) BAND2 — Not used. (Open) IF-B — Not used.
SECTION 5 EXPLODED VIEWS NOTE: • -XX, -X mean standardized parts, so they may • The mechanical parts with no reference number When indicating parts by reference number, have some differences from the original one. in the exploded views are not supplied. please include the board name.
SECTION 6 DISPLAY ELECTRICAL PARTS LIST NOTE: • Due to standardization, replacements in the • RESISTORS When indicating parts by reference number, parts list may be different from the parts All resistors are in ohms. please include the board name. specified in the diagrams or the components METAL: metal-film resistor The components identified by mark ! or...
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TRANS TUNER DISPLAY POWER SW Ref. No. Part No. Description Remarks Ref. No. Part No. Description Remarks < VARIABLE RESISTOR > < EARTH > RV701 1-466-336-21 ENCODER, ROTARY (TUNING/SELECT) ECP900 1-690-880-51 LEAD (WITH CONNECTOR) < SWITCH > < TRANSFORMER > S701 1-554-303-21 SWITCH, TACTILE (SHIFT) ! PT901...