Question on Pin #'s

Sirius

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I'm working on a Defender with Issues. I've got a logic probe but was was confused on pin #'s. The schematics showing the CPU are clear as to pin #'s. The 7474's on the other hand aren't...unless I missed it. The CPU starts at pin 2 top left and goes straight down same side, then to bottom right and up, with pin 40 at the top right, (correct?).

Okay so with something like pin 2 of 7L? I know pin 1 is upper left. Where would pin 2 to be? Below pin 1 or upper right side?
 
DIP pin numbering always starts at the corner just left of (counter-clockwise of) the "notch end". Sometimes there is a dot to indicate pin 1; sometimes not.

Numbering always proceeds all the way along that same side, then goes straight across, and back up the oither side; ending across from pin 1.

The positions shown when ICs are depicted on schematics are generally NOT THE SAME as the physical arrangement of the pins on the IC. The pin numbers for each line are often printed outside of the "box" for the IC. Use this number, and standard IC pin numbering (or a datasheet) to find the proper physical pin on the device.
 
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For 99.9999999% of thru-hole DIP packages, as you are looking at it from the top and the notch facing to the North, pin 1 is at the top-left. Pin 2 is directly under pin 1. The numbering proceeds to the South of the device, then wraps around the other side going North until the last pin # is at the top-right.
 
That worked. Can anyone decipher these values?

Pin 2 of 7L = hi/lo/pulse
Pin 5 of 7J = hi/lo pulse
Pin 9 of 7J = hi
Pin 4 of 6R = hi
Pin 8 of 7P = lo/pulse
Pin 12 of 7P = lo/pulse

...a brief history. The machine was only supposed to need a power supply. When I plugged it in there was only 2 of 3 led's lit (no -5) on the power supply. After some point the -5 came back on and the the machine did it's growl and the screen was scrambled. After a few adjustments to the monitor and several restarts the screen was working properly. I finally got it to show either a ram or rom error, not sure which, it was late. I was able to get past that to "game over". I coined up the machine and played 3 games, after that it was all down hill! The screen went corrupt...kinda looked like "Klingon". Now only 3 led's light on the rom board, don't blink and stay lit. I cant say that I ever saw the 4th led ever light. Anyway, now there "was" no video and no growl...sigh!!! I got life back in the monitor after swapping the 2 7474's, but still no growl.

Come to find out there was a bad connection on the -5 fuse holder. I've since cleaned it and re flowed the solder connections on the power supply. Tested the power supply's in numerous spots (connectors and ram). Only suspect voltage was the 6.3vac. It's reading at about 4.5 & 5.5

...so any help would be greatly appreciated.
 
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