McIntosh-MC250-pwr-sm维修电路原理图.pdf

MC 250 SERVICE INFORMATION STARTING WITH SERIAL NO. 23L48 MCINTOSH LABORATORY INC. 2 CHAMBERS STREET BINGHAMTON, NEW YORK RadioFans.CN 收音机爱 好者资料库 MC 250 ELECTRICAL SPECIFICATIONS Power Output: 100 watts RMS continuous, 50 watts per channel operating simultaneously, into 4 ohm, 8 ohm, or 16 ohm loads. Harmonic Distortion: Less than 0.25% at rated power output from 20Hz to 20,000Hz. Intermodulation Distortion: Less than 0.25% for any combination of frequencies between 20 Hz and 20,000 Hz. Frequency Range: At rated output both channels: +0 to -0.25dB from 20Hz through 20,000Hz. Output Damping Factor: Greater than 10 for any output tap. Input Sensitivity capacitance values smaller than 1 are in microfarads (F); capacitance values greater than 1 are in picofarads ( p F ) ; inductors are in mi c rohen r i es (H). 2. Printed circuit board components are outlined on the schematics by dotted lines. The circled numbers on the dotted lines correspond to the numbers on the PC Board layouts. 3. The heavy lines on the schematics denote the primary signal path. 4. A l l voltages indicated on the schematics are measured under the following conditions : a. Use of an 11 megohm impedance VTVM. b. A l l voltages 10% w i t h respect to chassis ground. c. No signal at input terminals. d. AC input at 1 1 7 v o l t s , 50/60Hz. e. Front panel controls at: Left Gain Right Gain Mode Fully CCW Fully CCW Stereo 5. In units with Serial N o . s below 2 8 L 2 1 : R88, R89, R90 R49 R86 and R33 & R34 are 33k. 6. In units with Serial N o . s from 28L60 to 37L75, C5 & C6 are 180pF. Q21 Q25 BOTTOM TOP Q19 Q23 BOTTOM TOP Q20 BOTTOM LOCATION OF TRANSISTORS NOT ON PRINTED CIRCUIT BOARDS Q26 TOP Q22 BOTTOM Q24 TOP RadioFans.CN 收音机爱 好者资料库 MC 250 R E P L A C E M E N T PARTS All parts not listed are common items able from radio parts jobbers . Rep1acement parts may be obtained when by PART NUMBER from: Mclntosh Laboratory Inc. Customer Service Department 2 Chambers Street Binghamton, New York 13903 (telephone 607 723-3512) Symbol Number Cl1 , 12 C27,28 C29 C47,48 C51 ,52 C53,54 C55,56 C57 D1 ,2 D5,6 07,8 D13,14 D15,16 D18 D20 D25,26 D27,28 D31 ,32 Fl Q1 ,2 Q3, 4 Q5,6 Q7,8 Q9.10 Q11 ,12 Q15,16 Q17,18 Q19,20 Q21 ,22 Elect. Elect. Elect. Mylar Elect. Elect. Elect. Elect. si. Si . Si . Si . Si . Si . Si . Si . 2.5A Si. Si . si. Si . Si . Si. Si . Si . Si. Si . CAPACITORS Description 470F 4V 9300F 45V 80/80/1 50/50F 200/200/150/150V .47F 100F 15V 10F 25V 640F 25V 500F 50V DIODES reference diode rectifier diode rectifier diode rectifier diode rectifier diode rectifier diode rectifier diode rectifier diode rectifier diode rectifier diode FUSES c i r c u i t breaker TRANSISTORS NPN transistor NPN transistor PNP transistor PNP transistor PNP transistor NPN transistor NPN transistor PNP transistor NPN transistor PNP transistor obtain- ordered Part Number 066-136 066-106 066-095 064-045 066-127 066-005 066-157 066-137 070-046 070-022 070-022 070-O4 070-041 070-031 070-031 070-031 070-031 070-022 088-001 132-054 132-054 132-056 132-056 132-056 132-515 132-021 132-032 132-524 132-530 Q23,24 Q25,26 Rl R2 R43,44 R57,58 R59,60 S1 ,2 S3 Tl T2 T3 Si. NPN transistor 132-070 Si. NPN transistor 132-070 POTENTIOMETERS Left gain 134-206 Right/mono gain 134-206 RESISTORS Wirewound 3.6k 5W 139-065 Wirewound .56W 5W 139-048 Wirewound .33W 5W 139-071 SWITCHES Thermal cut out 153-007 Modeselector 153-008 TRANSFORMERS Power transformer 043-605 Output transformer (right) 043-667 Output transformer (left) 043-668 MISCELLANEOUS ITEMS Plastic feet 017-040 Owners manual 038-287 Gain control knob 090-017 Shipping carton 033-077 AC power cord 170-021 15C01047S-M1508 SCHEMATIC PART NO. 038-508 RadioFans.CN 收音机爱 好者资料库