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Chassis Part Symbol Defective Circuit
MMC102A R14457
Horizontal
Symptom solution Set would run for approximately 1 sec. and shutdown. Deflection functioned when forced on. Servicer found no horizontal pulse at pin 2 of U38302. Also no feedback pulse to base of Q14803. R14457 (1 ohm) off pin 8 of T14451 open. Replacement of resistor restored operation. Replace R14457 All three tubes were burnt right out of the box. This unit already had TV00-008 performed. I had the tech check the G1 voltage at turn off and it was not dropping down to negative voltage at turn off. It was staying around +10 volts. Checking resistance to ground on the G1 line we found it read 1K. Unhooking the red wires to the CRT assembly the resistance came back up. Found C25107 leaky. VGA input picture is narrow in 2H mode, scan B+ at 90vdc (should be 120vdc) found CR14809 had 76vdc on anode, leaky. Shutdown, pulsing. Found J14405 not seated properly, causing the xrp circuit to turn on . The 12 volt sense circuit voltage going to base of Q14706 measured 3.8 volts, causing Q14706 to turn on. The 12 volt goes through j14405. Did not have high voltage with Q14105 b width is incorrect in HDTV mode. Scan power supply was not coiming up ro 120 volts. Drive was present at Q14800 but incorrect waveform. Found C14802 open Unit was going into scan loss shutdown (pin 3 of U13101 low). Also the picture is shifted to the left. Forced on the deflection and monitored the hoirzontal pulse at pin 7 of the Hor. SIP board and found the waveform decreased at 25 vpp. The servicer found Q14904 shorted causing the problem.
MMC102A C25107 MMC101 GCE CR14809
Horizontal Horizontal
Replace C25107 replace CR14809
MMC101 GCE J14405 MMC101 GCE C14802
Horizontal Horizontal
Reseat J14405 replace C14802
MMC101 G Q14904
Horizontal
Replace Q14904
MMC101 CC U14354 MMC101 CC Q14451 MMC101 Q14451
Horizontal Horizontal Horizontal
Unit won't start. Forcing on the run power supply found that the high voltage circuit was OK. If you check for the horizontal pulse coming out of the deflection sip board it would come up and go back down. If you unhook the horizontal side of the yoke the pulse would come up and stay and the 40-volt pulse coming back to the defection sip was good. Checking the ZVC Scan supply it was running at 1H but checking the S-Cap Correction Circuit it was switched to 2 H. On unsoldering Base of Q14456 and Q14457 the unit would come up and run OK. Taking a eeprom out of a good defection sip and put it in this one unit runs fine. With the unit running initialize the deflection eeprom U14354. The unit comes up clicks three times, the fan starts, then the unit shuts down. The heat sink was missing from Q14451. Replaced heat sink. cycles, will not force on. No collector voltage at Q14807, found Q14451 shorted from collector to base.
Initialize U14354 or replace the deflection sip board Replace heat sink. replace Q14451
MM102A Q14451
Horizontal
The unit would not start. Forcing on the run power supply found that the voltage on Q14451 collector was running at 20 volts. Unsoldering the collector, the trace came up to 65 volts DC. Check the transistor from the base to emitter it check to be 75 ohms. Replace the transistor fix the set. Replace Q14451. Picture was pulled in on the sides. Checked TP14801 the voltage was 76 volts, it should be 123 volts. Q14800 was not running, checked Q14803 C it was low, found R14841 not soldered on one side. resoldere R14841 unit is pulled in on the sides. Scan B+ was at 76vdc when set was turned on, found CR14802 shorted killing the scan B+ power supply. replace CR14802 For the first minute the unit is on the picture is only about an inch or so wide with a bright vertical line on the leftt side of the image. It then goes to full screen and stays that way until the next time the setis turned on. Found bad solder connection at one end of L14456 replace R14456 at EY14470, and R14456 had increased in value to over 1k. resolder 14456 Shutdown during bright scenes, b+ drops. Found R14702 cracked , replaced it and the set now works properly Replace R14702 resolder EY14801 Yoke plug and socket melted on the unit. Found EY14801 and EY14802 (off T14800) with and EY14802 loose connections. resoldered EY14801 and EY14802 replaced crt (yoke burned) replace crt Pulled in on the side. Checking Q14803 the collector and emitter low. unsoldered the emitter and check the trace the voltage was zero. Found CR14802 shorted Replace CR14802 Cycles, Forcing the deflection circuit on the 80V P-P pulse was missing on T14451 (14). Removing one side of CR14703 the pulse returned. Measuring the diode it checked leaky. Replace CR14173 picture pulled in on the sides, C14814 leaky off emitter Q14803 replaced capacitor and restored width & pin replaced C14814 No start, found open connection at pin 1 of T14300. Then the set would cycle the 200 volt to the Kine board was activating the xray protect circuit. Found T14751 shorted. Replace T14751
DTV307G C R14841 DTV306G CC CR14802
Horizontal Horizontal
DTV306G L14456, CB R14456 DTV306G C R14702
Horizontal Horizontal
DTV306C B Yoke DTV306C B CR14802 DTV306C B CR14713 DTV306C B C14814
Horizontal Horizontal
Horizontal Horizontal
CTC211A T14751
Horizontal