Zenith-19M20-Sams-259-16电路原理图.pdf

PHOTO PACT* Folder ZENITH CHASSIS 19M20, U, Z, 19M21, U, UZ, Z VOLUME CONTROL ON-OFF SWITCH ZENITH MODEL CHANNEL SELECTOR SWITCH M1800R TRADE NAME Zenith i MODELS M1800E, M1800R, R1800EZ, R1800RZ, R1812EZ, R1812RZ M1800EU, M1800RU, R1800EUZ, R1800RUZ, R1812EUZ, R1812RUZ. M1800EZ, M1800RZ M2228R, M2229E, M2229R, M2230E, M2230R, M2230RZ2, Ma249E, M2249R, M2250E, M2250R, M2252E, M2252R, R2229EZ, R2229RZ, R2230EZ, R2230RZ, R2249EZ, R2249RZ, R2250EZ, R2250RZ, R2257EZ, R2257RZ, R2258EZ, R2258RZ . M2228RU, M2229EU, M2229RU, M2230EU, M2230RU, M2249EU, M2249RU, M2250EU, M2250RU, M2252EU, M2252RU, R2229EUZ, R2229RUZ, R2230EUZ, R2230RUZ, R2249EUZ, R2249RUZ, R2250EUZ, R2250RUZ, R2257EUZ, R2257RUZ, R2258EUZ, R2258RUZ M228RZ, M2229EZ, M2229RZV M2230EZ, M2230RZ, M2249EZ, M2249RZ, M2250EZ, M2250RZ, M2252EZ, M2252RZ , M2250RUZ CHASSIS 19M20 19M2OU 19M20Z 19M21 19M21U 19M21Z 19M21UZ MANUFACTURER Zenith Radio Corp. , 6001 Dickens Ave. , Chicago 39, Illinois TYPE SET Television TUBES Nineteen Receiver POWER SUPPLY 110-120 Volts AC-60 Cycle RATING 1. 6 Amp. (a 117 Volts AC TUNING RANGE Channels 2 Drive Cord Stringing thru 13 VHP, 14 thru 83 UHF, Video IF 45. 75 MC, Sound IF 41. 25 MC INDEX 6, 7 Photographs (Cont) (Intercarrier) , . . , 23 Trans. , Inductor Si Alignment Identification Horizontal Sweep Circuit Adjustments 11 Servicing in the Field Parts List and Descriptions . Photographs Cabinet-Rear View Chassis-Top View RF Tuner Resistor Identification 15 thru 18 Schematic (Alternate Tuner) Schematic (TV) 11 Trouble Shooting Aids 4 , 9 Tube Failure Check Chart . 3 Tube Placement Chart (Bottom View) 10, 21 Tube Placement Chart (Top View) . 14, 19 12, 20 8 22 13 2 21 5 R 5 -o to N N -i I is c- w c N N N HOWARD W. SAMS chart lists tubes whose failures are most likely to produce the indicated symptoms. Refer to tube placement chart for location and type of tube. POWER SUPPLY FAILURE No raster, no sound - V18 LOSS OF PICTURE OR SOUND No pic, no sound, has raster - V2, V3, V4, V5, V6 No pic, no sound, has snow - VI, V2, V3 No pic, has sound, has raster - V6, V7, V19 Has pic, no sound - V8, V9, V10 Overloaded picture -V7 SYNC FAILURE No vert, sync - VJ, Vll Nohoriz. sync -Vll, V13, V14 No vert, or horiz. sync - Vll SWEEP FAILURE No raster, has sound - V14, V15, V16, VI7, V19, Fuse (Ml) No vertical deflection - V7, V12 Poor vert, linearity or foldover - V7, VT2 Poor horiz. linearity or foldover - V14, V15, VI6 Narrow picture - V14, V16, V17, V18 Vert, off freq. - V7, Vll Horiz. off freq. -Vll, V13, VM i 10 N H - I K) c - NC V* N N SET 259 FOLDER 16 PAGE 5 RadioFans.CN ALIGNMENT INSTRUCTIONS 1. 2. 3. 4. The high voltage lead should be securely taped and kept away from the chassis. Do not remove the horizontal oscillator tube (V14) to disable the high voltage . VIDEO IF ALIGNMENT Connect the negative lead of a 2 volt bias supply to the ungrounded side of C31. Connect the positive side to chassis. Connect the synchronized sweep voltage from the sweep generator to the horizontal input of the oscilloscope for horizontal deflection. DUMMY ANTENNA 470MMF SWEEP GENERATOR COUPLING High side to pin 1 (grid) of 6CB6 (V5). Low side to chassis. High side to point . Low side to chassis . SWEEP GENERATOR FREQUENCY 43MC (10MC Swp) MARKER GENERATOR FREQUENCY 39.75MC 45.75MC 39.75MC 41.25MC 47.25MC 42.75MC .OMC 45.75MC CHANNEL Any non interfer- ing channel CONNECT SCOPE Vert. Amp. thru 10KSJ to point . Low side to chassis ADJUST A1.A2 A3.A4, A5 A6, A7, A8,A9 REMARKS Attenuate generator output for 3 volts peak to peak on scope. Adjust for response curve of maximum amplitude and sym- metry similar to Fig. 1. Remove bias battery. Use maximum scope gain to amplify trap region of response curve as in Fig. 2. Adjust for MINIMUM marker amplitude. Reconnect bias supply. Attenuate sweep generator output to maintain not more than 3 volts peak to peak on scope. Alternately adjust A6 thru A9 to obtain response similar to Fig. 3. A6 affects the high side and A7 affects the low side of the response curve. OSCILLATOR ALIGNMENT The master oscillator adjustment, A10, is to be made only if the individual channel oscillator adjustment fails to bring the channel within the range of the fine tuning control. If channels 2 thru 6 fall within the range of the fine tuning control but the higher channels do not , slight adjustment of A10 may be necessary to bring in the higher channels , Connect the negative lead of the bias supply to the ungrounded side of C31. Connect the positive lead to chassis. Adjust for -1 volt at C31. Turn up the scope gain so that the sound trap notch in the response curve becomes visible,. Connect the synchronized sweep voltage from the sweep generator to the horizontal input of the oscilloscope for horizontal deflection. The sweep generator output lead should be terminated with its characteristic impedance, usually 50 ohms. Set the fine tuning control to the mid-position of its range. DUMMY ANTENNA Two 120S2 Carbon Resistors SWEEP GENERATOR COUPLING Across antenna ter- minals with 120S2 in each lead. SWEEP GENERATOR FREQUENCY 57MC (10MC Swp 63 MC (10MC Swp 69MC (10MC Swp 79MC (10MC Swp 85MC (10MC Swp 177MC (10MC Swp 183MC (10MC Swp 189MC (10MC Swp 195MC (10MC Swp 201MC (10MC Swp 207MC (10MC Swg 213MC (10MC Swp MARKER GENERATOR FREQUENCY 59.75MC 65.75MC 71.75MC 81.75MC 87.75MC 179.75MC 185. 7 SMC 191.75MC 197.75MC 203.75MC 209.75MC 215.75MC CHANNEL 2 3 4 5 6 7 8 9 10 11 12 13 CONNECT SCOPE Vert. Amp. thru lOK.fl to point . Low side to chassis ADJUST All A12 A13 A14 A15 A16 A17 A18 A19 A20 A21 A22 REMARKS Adjust to place sound marker in trap notch as in Fig. 4. FIG.FIG.2FIG.3FIG.4 PAGE 6 RadioFans.CN ALIGNMENT INSTRUCTIONS (cont) HF AND MIXER ALIGNMENT Remove the bias supply from C31 and connect a jumper from the tuner AGC lead (yellow) to chassis. Connect the synchronized sweep voltage from the sweep generator to the horizontal input of the oscilloscope for horizontal deflection. The sweep generator output lead should be terminated with its characteristic impedance, usually 50 ohms. DUMMY ANTENNA Two 120S2 Carbon Resistors SWEEP GENERATOR COUPLING Across antenna ter- minals with 120S2 in each lead. SWEEP GENERATOR FREQUENCY 69MC (10MC Swp) 201MC (10MC Swp) MARKER GENERATOR FREQUENCY 67.25MC 71.75MC 199.25MC 203.75MC CHANNEL 4 11 CONNECT SCOPE Vert. Amp. thru 10KS3 to point . Low side to chassis. ADJUST A23, A24, A25 A26, A27, A28 REMARKS Adjust for response similar to Fig. 5. Adjust A26 and A27 for symmetrical response similar to Fig. 6. Adjust A28 for proper band width. Repeat steps 5 and 6 until best overall symmetrical response is obtained. Remove jumper from tuner AGC terminal to chassis. SOUND IF ALIGNMENT Connect an attenuator Zenith part #3-17203 or equivalent) in series with the receiver antenna. Tune in a tone modulated TV signal and adjust the attenuator until the signal falls below the limiting level of the 6BN6 limiter detector, as evidenced by a hiss similar to superregeneration. Adjust the sound take-off transformer (A29, A30) the sound IF transformer (A31) and the quadrature coil (A32) for maximum sound of best quality. Adjust the buzz control (R9) for minimum intercarrier buzz. II the intercarrier buzz cannot be eliminated with the buzz control check the setting of the AGC delay control adjustment. II during the sound IF alignment the signal rises above the limiting level (hiss disappears) increase the attenuation until the hiss returns. UHF TUNER ALIGNMENT 7. 8. 9. Alignment of the UHF tuner should not be attempted unless proper test equipment is available. Switch the receiver to the UHF position . Connect the negative lead of a 2 volt bias supply to the ungrounded side of C31. Connect the positive lead to chassis. Adjust the sweep generator output to provide 3 volts peak to peak on scope, Connect the synchronized sweep voltage from the sweep generator to the horizontal input of the oscilloscope for horizontal deflection. The sweep generator output lead should be terminated with its characteristic impedance, usually 50 ohms. DUMMY ANTENNA Fig. 8 SWEEP GENERATOR COUPLING Across UHF antenna terminals thru matching network (Fig. 8). SWEEP GENERATOR FREQUENCY 713MC (10MC Swp) 473MC 887MC (10MC Swp) MARKER GENERATOR FREQUENCY 711.25MC 471.25MC 885.25MC CHANNEL 54 14 83 CONNECT SCOPE Vert. Amp. thru IOKSI to point . Low side to chassis. ADJUST A33.A34, A3 5 A36, A37 A38 REMARKS Tuner rocket arm should be in the horizontal position. If necessary, loosen set screw and adjust tuner shaft so that rocker arm is horizontal when the channel indicator is set to channel 54. Do not adjust A33 unless oscillator calibration is off more than three channels. If necessary, adjust A33 to place video market at 50% on response curve as in Fig. 7, The image (weaker re- sponse) will appear also. The response to- ward the counter clockwise position of A33 is the correct response. Adjust A34 and A35 for maximum amplitude and symmetry of response similar to Fig* 7. Check for response similar to Fig. 7. If oscillator is off more than 3 channels adjust the oscillator travel (osc., mixer and ant, travel adjustments are the three round thumb screws on top of tuner) adjustment to scale. Care must be used in making this adjustment so as not to move the rocker arm out of its bearing. Set the mixer and antenna travel adjustments for maximum response on scope. Adjust A36 to place video marker at 50% as in Fig. 7. Adjust A37 and A38 for maximum amplitude and symmetry of response similar to Fig. 7. o K O N N -I I Is / c N N N FIG.5 F IG.6 FIG. 7 ON CONTINUOUS TUNER FIG. 8 PAGE 7 RadioFans.CN RESISTANCE MEASUREMENTS Item V 1 V 2 V 3 V 4 V 5 V 6 V7 V 8 V9 V 10 V 1 1 V 12 V 13 V 1 4 V 15 V 16 V 17 V 1 8 V 1 9 Tube 6BK7A 6U8 6CB6 6CB6 6CB6 12BY7 12 AX 7 6AU6 6BN6 6AQ5 6CS6 6AH4GT 6AQ7GT 6SN7GTA 6BQ6GT 6AX4GT 1B3GT 5U4G 17LP4 Pin 1 t750B tlO. 3KS2 1. IMeg 80KSJ 270n 15n 5 Meg 100KB 350! 350KB 19KB 1. 8Meg 2Meg 47KB t!2KB INF PINS INF OB Pin 2 60KB 68KS! 500B 80KB 420n 3Kn 270KB on . 3n 680n on .in IMeg 215KS2 .in INF 1 - 8 30KB lOOKn Pin 3 INF ylOOKB .in .1S2 .in isn 40Kn .in .m on an 1. SMeg on on 6. 8KB 700KS! HAVE teen PIN 6 250KB Pin 4 .in .in on on OB on on on on .IB OB INF 3Meg 32KB T12KB INF INFINITE 16B PIN 10 32Kfi Pin 5 on on 1470B tSOOB t8. 2KB on on f32Kn t22KB 1.4KB TlOOKB t460n t47Kn teen 470KB t7on RESISTJ INF PINU tSOOKSJ Pin 6 INF I300B i470n t50on t8. 2KB .IB 1 800KB T32Kn 4. 6B tsoon i. 8Kn INF 470n 10KB 470KB 4. 2n NCE isn PIN 12 .in Pin 7 3. 3Meg on on aoKn on tsKn 3. 9Kn on 680KB 350KB jLlOMeg OB .IB on OB .in INF Pin 8 47B 2.2KH t22Kn 7. 5Kn i. 8Kn on .IB on on 30Kn Pin 9 on 4.4KB 15B .IB TUP UAP 9. 4B TDPTSP 414B t MEASURED FROM PIN 2 OF V18 i MEASURED FROM PIN 7 OF V4 MEASURED FROM PIN 3 OF V16 1ST VIDEO IF 2ND VIDEO IF BOTTOM VIEW VIDEO OUTPUT LV RECT HORIZ 8 VERT - SWEEP PROTECTION HORIZ DISCH TUBE PLACEMENT CHART PAGE 8 RadioFans.CN VHP TUNER-RIGHT SIDE VHP TUNER-LEFT SIDE PAGE1O RadioFans.CN WIDTH ADJ. HORIZ. DRIVE CABINET-REAR VIEW HORIZONTAL SWEEP CIRCUIT ADJUSTMENTS - N N -i X is c - ui N N Turn the set on and tune In a TV station, preferably a test pattern. Set the horizontal hold control adjustment until the picture synchronizes horizontally. Adjust the horizontal Drive trimmer (Bl) counter clockwise for maximum width. Adjust the width for a picture slightly wider than necessary to fill the picture mask horizontally by sliding and turning the brass sleeve on the neck of the picture tube. AGC DELAY CONTROL ADJUSTMENT Connect the vertical amplifier of an oscilloscope through a 10KSJ resistor to point Aluminlzed Circuit change necessary CAPACITORS Capacity values given in the rating column are in mfd. for Electrolytic and Paper Capacitors, and in mmfd. for Mica and Ceramic Capacitors. ITEM No. CIA B C C2A B C D C3 C4 C5 C6 C7 C8 C9 CIO Cll C12 CIS C14 CIS C16 C17 CIS C19 C20 C21 C22 C23 C24 C25 C26 C27 C28 C29 C30 C31 C32 C33 C34 CSS C36 C37 C38 C39 C40 C41 C42 C43 C44 C45 C46A B C47 C48 C49 C50 C51 C52 CSS C54 C55 C56 RATING CAP. 40 .80 430 .40 10 A 10 100 40 40 40 40 2.5-6 400 800 400 2.2 400 400 400 .85-2.: .6-3 800 100 19 2 400 2 4.5 10 5.5 400 470 24 9 6 .1 330 1000 .015 1000 470 1000 470 470 1000 47 .022 .1 3.3 50 1000 1000 10 .01 10000 .0068 .0033 27 .0022 .022 .33 .0022 VOLT 400 1 400 0 1 450 1 450 I 400 ( 50 J 400 200 200 200 200 1000 600 600 600 200 600 REPLACEMENT DATA ZENITH PART No. 22-2437 22-2483 22-2519 22-2519 22-2519 22-2519 22-2221 22-2401 22-2331 22-2401 22-2468 22-2401 22-2401 22-2401 22-2453 22-2504 22-2331 22-2407 22-2406 22-2536 22-2557 22-2536 22-2500 22-2411 22-2449 22-2557 22-2217 22-1777 22-2309 22-7 22-7 22-2302 22-7 22-2524 22-2217 22-2112 22-2467 22-1781 22-1777 22-2343 22-2460 22-2553 22-2378 22-3 22-3 22-2495 22-1785 22-2396 22-1845 22-2129 22-2159 22-2161 AEROVOX PART No. AFH3-46 AFH4-83 BPD-0008 SI2 . 2NPO BPD-0008 SHOO SI2 . 2NPO SI10NPO SI470 P288-1 BPD-001 P288-1 BPD-001 SI470 BPD-001 1469-0005 SI470 P288-1 BPD-2X001 P28 Vt C - J- w C N N SET 259 FOLDER 16 PAGE 15 RadioFans.CN CAPACITORS (cont) PARTS LIST AND DBS RESISTO ITEM No. C57 C58 C59 C60 C61 C62 C63A B C64 C65 C66 C67 C68 C69 C70 C71 C72 C73 C74 C75 C76 C77 C78 C79 C80 C81 C82 C83 C84 C85 RAT CAP. .1 1000 1000 .022 .033 .01 1000 1000 10000 100 120 .001 0047 .15 .001 .1 680 .0015 1000 1000 680 220 .047 .15 72 4.5 7 470 .15 .01 NG VOLT 600 500 500 200 200 400 500 200 400 200 200 200 500 400 500 500 400 400 2000 200 200 REPLACEMENT DATA ZENITH PART No. 22-1841 22-2545 22-2545 22-1781 22-1840 22-1846 22-2545 22-3 22-9 22-2505 22-1839 22-1842 22-2166 22-1839 22-1777 22-2340 22-1785 22-2163 22-2112 22-2387 22-2458 22-1775 22-2341 22-2522 22-2375 22-3 AEROVOX PART No. P688-1 1464-001 1464-001 P4 88-01 BPD-2X001 BPD-01 BPD-0001 1469-0001 P688-001 P688-001 P288-1 1469-0007 P488-0015 1468-001 P488-047 SI470 P288-15 P288-01 CENTRALAB PART No. DF-104 D6-103 DD2-102 DD-103 DD-101 D6-102 D6-102 DF-104 D6-152 DF-503 D6-471 D6-103 CORNELL- DUBILIER PART No. CUB6P1 1R5D1 1R5D1 CUB4S1 DK069 K082 G042 22B5T12 CUB6D1 CUB GDI PJ2P1 LR5T68 CUB4D15 1H5D1 CUB4S47 PJ2P15 PJ2S1 ERIE PART No. GP2-333-103 812-001 811-01 801-0001 GP2-333-102 GP2-333-102 GP2-333-152 GP1K-471 MALLORY PART No. PT601 MCE-255 MCE-255 PT411 DCD-521 DC-511 UC-531 MCE235 PT621 PT621 PT401 PT4215 MCE255 PT4147 UC-5347 PT4015 PT411 SPRAGUE PART No. 6TM-P1 MS-21 MS-21 4TM-S1 5HK-2D1 5HK-S1 5GA-T1 MS-31 6TM-O1 6TM-D1 2TM-P1 MS-37 4TM-D15 MS-21 4TM-S47 5GA-Q47 2TM-P15 2TM-S1 NOTES Nole 6 CONTROLS ITEM No. RIA B C R2A B R3A B R4A B R5A B R6A B R7A B R8 R9 R10A B RATING RESIST- ANCE IMeg Shaft Switch 7. SMeg Shaft lOMeg with IMeg stop Shaft 200KO Shaft 75KO Shaft 25000 Shaft 15KO Shaft 50000 6000 4.5Meg Shaft WATTS 1 1 i J 1 i 4 1 z REPLACEMENT DATA ZENITH PART No. 63-3199 Not Req. Not Req. 63-2919 Not Req. 63-2946 Not Req. 63-2837 Not Req. 63-2896 Not Req. 63-2971 Not Req. 63-2976 Not Req. 63-3201 63-3167 63-3208 Not Req. IRC PART No. Q13-137 Not Req. 76-1 Qll-142 RQ Qll-143 RQ