Data East Guns and Roses GNR MPU Lamp Matrix Diagnosis and Repair скачать в хорошем качестве

Data East Guns and Roses GNR MPU Lamp Matrix Diagnosis and Repair

Data East Guns and Roses GNR MPU Lamp Matrix Diagnosis and Repair Most lamp matrix issues on Data East and Williams System 11 MPUs are caused by (probability order)... ...failed column or row drive transistors ...pre-driver transistors in the column circuitry (2N6427) ...upstream column drivers (74LS08) or row drivers (7406) ...lamp matrix 6821 PIA ...current limiting resistors. This board was no exception. It had one failed TIP-42 and 3 failed 2N6427s. My "standard updates" to these boards include... ...replace CN17, the power header ...inspect for alkaline corrosion ...install NVRAM ...inspect and replace other headers as necessary http://ChrisHiblerPinball.com/Contact