Technics SX-PR700

PRECAUTIONS BEFORE SERVICING
Mi Precautions for measuring of the output waveforms.
1.
2.
3.
The waveform was measured with a “National Digital Storage Oscilloscope VP-5730A”. Therefore the waveforms of musical
tone signals shown may differ somewhat due to the difference in the timing of triggering.
Since the 1/10 test probe is used, the indicated voltage value on the bottom part of each waveform photo is 1/10 of the actual
value (e.g. 0.2 V/cm should be 2.0 V/cm).
To measure the waveforms, first set this unit to the self-diagnostic mode (refer to page I-17, No. 3). The Wave ROM output will
then be output as a sine wave to facilitate the servicing check.
@ Important safety notice:
Components identified by a /\ mark have special characteristics impotant for safety.
When replacing any of these components, use only manufacture’s specified parts.
i Symbolic Marks
The symbolic marks for resistors and capacitors which used in this circuits are classified as following TABLE-1 and TABLE-2.
1.
RESISTORS
* Resistors without symbolic mark are FIXED CARBON FILM RESISTORS (ERD-type).
* All resistors are 1/4 WATT, +5 % TOLERANCE unless otherwise designated in schematic diagrams.
(TABLE-1)
SYMBOL SPECIFICATION SYMBOL SPECIFICATION
® Fixed Carbon Film Resistors ® Fixed Metal Film Resistors
“FLAME-PROOF’” (ERD—F—type) “FLAME-PROOF” (ERX—type)
Fixed Wire Wound Resistors Fuse Type Fixed Metal Oxide Film Resistors
“FLAME-PROOF” (ERF—type) “FLAME-PROOF” (ERQ—type)
® Fixed Metal Oxide Film Resistors Fuse Type Fixed Carbon File Resistors
“FLAME-PROOF” (ERG—type) “FLAME-PROOF’” (ERD2FC—type)
Fixed Metal Film Resistors (Precision and High Stability) (ERO—type)
CAPACITORS
* Capacitors without symbolic mark are POLYESTER CAPACITORS. (ECQM-type, ECQG-type, +10 % Tolerance)
* Polarized capacitors without symbolic mark are Aluminum Electrolytic Capapcitors. (ECEA-type, 20 % Tolerance)
(TABLE-2)
SYMBOL SPECIFICATION TYPE
| @ | Non-Polarized Electrolytic Capacitors ECEA_KN_type
Non-Polarized Electrolytic (for Network system) ECEA_Y_type
PO al Tantalum Solid Electrolytic Capacitors ECS_type
| @® | Metalized Plastic Film Capacitors (TF Series) ECQV_type
Temperature Compensating Ceramic Capacitors ECC_type
High-Dielectric Constant Ceramic Capacitors ECK_type
ECR_type
Axial Lead Ceramic Capacitors ECB_type
Metalized Polyester Film Capacitors for Across the Line ECQ_EW_type
Aluminum Electrolytic Capacitors for Smoothing Circuit ECES_type
Multilayer Ceramic Chip Capacitors ECUV_type