This shows the front of the R220 shift register before and after replacing the bad components. Notice the hand written D18 beside the diode. That was done by the person who did the previous repair. DEC provided schematics but not the card component layout information. The previous person had labeled some of the components to help in his troubleshooting.
I lifted one end of the marked resistor when the resistor value measured wrong to see if the resistor was bad. The value was wrong due to the short instead. The shiny spot around the resistor lead at the bottom of the board is the flux I used repairing the board which I hadn't fully cleaned up. The flux was more visible in the picture than looking at the board. I have cleaned it up better.
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