User manual PIONEER SA-610 service manual

[. . . ] O 5 o 1o 0 0 0 H 2 ) L / . , PHONO 130mV O u t p u t( L e v e l ) TAPERECl, 2. . A, B, OFF Miscellaneous P o w e rR e q u i r e m e n t s AC 120V, 60H2 PowerConsumption . . . 100W(UL) Dimensions . 4 2 O ( W x 9 4 ( H ) x 3 4 7 ( D )m m l 1 6 - 9 / 1 6 ( W )3 - 1 1 l 1 6 ( H ) 1 3 - 1 1 / 1 6 ( Dn x x i) W e i g h t( w i t h o u tp a c k a g e ) 6 . 9 k g( 1 5 l b 3 o z ) Furnished Parts Operatinglnstructions . . . . . . . . 1 NOTE: Specifications and the design subject to possible modifications without notice due to improvements. * Measured pursuant to the Federal Trade Commission, s Trade Regulation rule on Power Output Claims for Amplifiers. 2 . [. . . ] There' fore, when replacing, be sure to use parts of identical designation. m (t . J!g!r. - K n o b( B A L A N C E I AAB. 223 Leverknob ( L O U D N E S S , A P E2 ) T AAD. 2OO 6 siA-610 Front View with Front Panel Removed F l u o r e s c e n ti n d i c a t o r t u b e AAV-O06 V a r i a b l er e s i s t o r( B A S S . T R E B L E ) ACT-127 Slide rotary switch (FUNCTION) A S X - I1 3 sl ide rota ry r*i t"tr -------]-=---. ' (SPEAKERS) : I" ASE-oo3 I L e v e rs w i t c h ( P O W E R ] | , , ll '!'tlr ' I o L:---Variable r e s i s t o r( V O L U M E ) 'l I tu " V a r i a b l er e s i s t o r( B A L A N C E ) ASK. 520 Headphones . jack AKN-023 ACT-130 -Lever s w i t c h( T A P E2 ) ASK. 172 Leverswitch ( LOUDN ESS) ASK-171 f L e v e rs w i t c h ( S U B S O N I C , O N E ) T A S K - 17 1 Top View with Bonnet Removed rl|r j Powertransformer ATT-667 A F a m p l i f i e ra s s e m b l y GWK. 144 Switch assembly GWS-215 Switch assembly GWS-216 Volume assembly GWX459 t- t Headphones ssembly a GWX460 Tonecontrolassembly GWG-138 I AC socker AKP. O32 RearPanel View 1i Power code ADG-023 T e r m i n a l{ I N P U T ) AK8. 064 T e r m i n a l( T A P E 1 ) AKB-063 Strein reliel AEC-327 Terminal(SPEAKERS) AKE-051 5. BLOCK DIAGRAM swtrcHEs: st Fu&trox luxEP-M-raPEI-AUX 32 t3 54 55 s6 se fAPE?ouoils Su6oirt(t5Hrl SPEAXERS &sR ioilE ON - 6F ox - gll Ox - 6 O'F-A-' ox -!Il or _lI! 6 . L EV E L DI A G RA M l}. tlJ"roo't (eo) xeai pnone AUX /TUNER 15OmV siA-61 cl n 7 . C I R C U I TD E S C R I P T I O N S Equalizer Amplifier The 54, -610 features a 3-stage direct-coupled equalizer amplifier for greater reduction of noise and distortion. Besides the use of an ultra low-noise transistor (25C26O2) in the first stage, the adoption of low impedance input resistance and equalizer circuit has contributed to an S/N ratio of at least 82dB (at 2. 5mV input, IHF-A). Power Amplifier This all stage direct-coupled pure complementaly SEPP circuit features a current mirror load differential amplifier in the first stage, and incorporates the tone control circuit in the NFB loop. Although the incorporation of the tone control circuits in the power amplifier stage reduces the number of elements that the signal has to pass through, and thereby further reduces noise, distortion, and cost, the power stage does require a higher gain and a higher degtee of stability. In the SA-610, this high gain and high stability are achieved by a cunent mirror load differential amplifier in the first stage and by the use of a constant current circuit for the load of the predriver stage. Furthermore, the tendency for the pre-driver stage capacitance impedance load to cause deterioration in the high end frequency responseis suppressedby inserting a capacitor (C) between the emitter of the pre-driver stage (Q2) and the baseof the constant current circuit (Q1) as shown in Fig. At frequencies where the reactance of this capacitor may be ignored, the push-pull action of Ql and Q2 servesto counteract the high end frequency response deterioration. The power amplifier stage is a complementary 2-stage' Darlington connection, resulting in an output power rating of 45W + 45W (8Q, 20Hz2OkHz\, harmonic distortion of less than O. O37o (20H2 20kHz at rated output), and output power bandwidth of 5Hz - 50kHz (0. O3% THD). Certainly a superb performance for an amplifier of this classis obtained. /. Constant circuit current rl I !f' Protection Circuit Besides protecting the speakers if a DC voltage should happen to appear at the power amplifier stage outputs, this circuit also mutes the signal path when the power switch is turned on and off (SeeFig. If for any reason a DC voltage (in excess of about tbV) should happen to appear in the output of the power amplifier stage, it is detected immediately by either Q23 or q24. In either case, Q25 is also turned off, thereby opening the relay contact to disconnect the power amplifier stage from the speakers. , The muting action when the power switch is turned on is achieved by delaying the rise of the Q25 base potential by means of the R95/C77 time constant circuit. When the power switch is turned on, C77 is charged up via R95, thereby increasing the voltage across both ends of this capacitor. Therefore, when replacing, be sure to use parts of id. entical designation. Key No. Description Bonnet case Screw Lever knob Front panel assembly Knob Knob Knob Screw Bottom plate Screw 1. 10. ANE. 269 ABA-079 AAD. 2OO AN8. 847 AAB. 222 AAB. 223 AAB. 221 ABA-186 AB4-066 1;r InteriorComponent lK'? il 32 34 um ;l _^sY'2o 44 29 30 - - 36, 2ssl- ffu. . Q Nf-, ro '9;i, 38 w Y siA-cil tt^ o PartsList Key No. Description Power transformer Wire clip Frame Switch assembly Lever switch Capacitor Headphones assembly Tone control assembly F. L. [. . . ] Symbol & Description PartsList of SwitchAssembly (GWS-216) Part No. Symbol & Description 56 Slide rotary switch (FUNCTION) ASX-13 | coMA 303J 50 coMA 124K50 cosA 270KsO CQMA 122K50 coMA 562K50 Note: c63, C64 c65, C66 c67, C68 c69, C70 c73, C74 When ordering resistors, conuert the resistance ualue into code form, and then rewrite the part no. VR4 Variable resistor R 8 1 - R 9 0 , R 1 0 1 , 1 0 0 R PartsList of VolumeAssembly (GWX-4S9) Part No. Symbol & Description VR2 V a r i a b l e r e s i s t o r( V O L U M E ) ACV-184 RESISTORS Part No. PartsList of Headphones (GWX-460) Assembly Part No. [. . . ]