Zenith ZCM-1490 Service Manual page 6

Troubleshooting Charts ..................... 6-5
5-1. ZCM-1490 Block Diagram .... , ...... , .. 5-2
Resistance Measurements ................. 6-11
5-2. Video Amplifer Section (Green) ......... ,5-4
5-3. Horizontal Output Amplifier ... , ......... 5-7
Chapter 7 - Parts List
5-4. Blanking Pulse Circuit ................ 5-10
5-5. E-W Waveform Generator ............ 5-10
Chapter 8 - Schematics and Waveforms
5-6. E-W Regulator ...................... 5-11
Waveform Explanation ..................... 8-1
5-7. N-S Waveform Generator ............. 5-12
5-8. N-S Output ........................ 5-14
Figures
6-1. CRT Anode Discharging ........... -.... 6-2
6-2. AC Leakage Voltmeter Circuit ........... 6-3
1-1 . ZCM-1490 Color Video Monitor .......... 1-1
6-3. General Troubleshooting Chart .......... 6-6
6-4. Video Board Troubleshooting Chart ...... 6-7
2-1. ZCM-1490 Front View ................. 2-1
6-5. Deflection Board Troubleshooting Chart ... 6-8
2-2. ZCM-1490 Rear View ................. 2-1
6-6. Pin Board Troubleshooting Chart ........ 6-9
2-3. Subminiature D-type Connector ......... 2-2
6-7. Power Supply Troubleshooting Chart .... 6-10
3-1. CRT Anode Discharging ............... 3-1
7-1. Exploded View ..................... 7-21
3-2. Rear Cover Removal .................. 3-2
3-3. Rear Chassis Panel Removal ........... 3-2
8-1. Oscilloscope Display Information ........ 8-1
3-4. Video Board Removal ................. 3-3
8-2. Video Board Component View
3-5. Control Board Removal ................ 3-4
. (Component Side) .................... 8-5
3-6. PIN Board Removal. .................. 3-4
8-3. Video Board Component View (Foil Side). -.8-6
3-7. Fan and Bottom Panel Removal ......... 3-5
8-4. Video Board Schematic ................ 8-7
3-8. Support Bracket and Shield Removal ..... 3-5
8-5. Deflection Board Component View
3-9. D~flection Board Assembly Removal ..... 3-6
3-10. Deflection Board Removal.' ............. 3-7
- (Component Side) .................... 8-9
8-6. Deflection Board Component View
3-11. Power Supply/Focus Board
(FOil Side) ......................... 8-10
Assembly Removal ................... 3-8
8-7. Horizontal Deflection/High Voltage
3-12. Power Supply and Dynamic Focus
Schematic ......................... 8-11
Board Removal ...................... 3-9
8-8. Vertical Deflection/Mode Selection
3-13. CRT Lead Dress and Removal ......... 3-10
Schematic ......................... 8-13
8-9. PIN Board Component View
4-1. Video Board Adjustment Locations ....... 4-2
(Component Side) ................... 8-15
4-2. Deflection Board Adjustment Locations ... 4-3
8-10. PIN Board Component View (FOil Side) ..
8~16
4-3. PIN Board Adjustment Locations ........ 4-4
8-11. E-W Generator/Regulator Schematic .... 8-17
4-4. Dynamic Focus Board Adjustment
8-12. N-S Generator/Output Schematic ....... 8-19
Locations. : ......................... 4-4
8-13. Dynamic Focus Board Component
4-5. Control Board Adjustment Locations ...... 4-5
View ......................... '" .. 8-21
4-6. CRT Gun Waveforms ................. 4-9
8-14. Dynamic Focus Schematic ............ 8-21
8-15. Control Board Schematic ............. 8-21
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