CTC210_211_Scan_Loss_Detect_Trblshoot_A2D7C1C0BF638A90E0339DFEEACC8A90_25.pdf part of RCA D52130 RCA_CTC210-211_01.rar, Large File 6 pare RAR Folder containing: Flow Charts, Tech Tips, Trouble Shooting Manuals, Updates, Module Training, and Symptom Fixes text manual preview

Text preview for : CTC210_211_Scan_Loss_Detect_Trblshoot_A2D7C1C0BF638A90E0339DFEEACC8A90_25.pdf part of RCA D52130 Large File 6 pare RAR Folder containing: Flow Charts, Tech Tips, Trouble Shooting Manuals, Updates, Module Training, and Symptom Fixes

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Troubleshooting Scan Loss Detect Symptom: "Cycling" Shutdown
NOTE: In order to effectively troubleshoot the horizontal drive circuit, the scan loss detect circuits must be defeated. Refer to the Scan Loss Detect section. 1. Obtain latest Chipper Check failure code and check circuit areas accordingly. IMPORTANT: DO NOT reinitialize the EEPROM! 2. Remove & secure CRT CBA. 3. Check standby and main power supplies. 4. Check for horizontal drive at TP14301 (connect scope across primary of T14300). 5. Check base drive of Q14451 (should be very similar to TP14301). 6. Check collector waveform of Q14451 (amplitude & shape are critical). 7. If there is NO collector waveform present, check Q14451 and Scan B+ generator circuits. 8. If waveform is present and the shape is correct but approximately ½ amplitude, check for an open in yoke and yoke return circuitry. 9. If waveform is low and distorted (ringing), unplug horizontal yoke. 10. If waveform is still distorted, check all components in Q14451 collector circuit.