First test D901012 feet have input waveform, sawtooth wave generator, the test video channel waveforms, including IC307, IC306, IC304 input and output waveforms are normal, IC316 (MN5185) delimit as normal control chip input waveform, the output end to change. To test its potential for pin, found that the 118 foot high potential requirements with the calibration value deviation. Lmuservice manual download site
Lmuservice manual download site
Along the figure for 118 feet blanking control signal input end IC318 (TC7S08F) as a gate, sending two blanking signals in IC316 118 feet. Potential test IC318 each foot, its (1), (2) feet about 1 V, voltage of 3.5 V, 5 feet touch IC318 chip surface temperature, increased significantly, IC318 has been damaged. Drawings by hand without the chip, saw the input (1) and output (4), (2) the feet of the direct current (dc) are the same, try to (1), (2) after foot and thread lead to IC316 118 feet, boot watch images, higher resolution obviously, black line has disappeared. But considering the machine circuit requirements should not be so access, so use a 74 ls08 (two positive and gate) with access to the original IC318 pin, lead to 74 ls08 good with scotch tape. The unused pins with good insulating tape, in a free location.Lmuservice manual download site
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