Tech Tip #15 - KNOW your machine !!
When was the last time you were trying to fix+measure things on your machine and didn't really know what you were looking at? or if it's good or bad???
So, While your pin is working 100% go grab a multimeter and spend some time measuring the voltages on ALL test points on ALL boards, and even measure voltages on the main chips too. (power supply pins mainly).
Write all the figures into your fave spreadsheet program or a piece of paper and store a copy in the headbox of each pin you have.....
Later on when things go mental, you'll be thanking yourself you have some GOOD readings to compare too.
Even if a voltage was 5v and now shows 4.6v in faulty mode, at least you have a known-reference to indicate a change occurred.
This will pinpoint most probs straight to the culprit board and it'll save you weeks of measuring and consulting manuals that dont always show ALL readings anyway.
Also note, you might want to take reading when the pin is in 'attract' mode, and also in 'play' mode, and note if things change as there might be a few chips or relays that change state between the 2 modes.
To take things to the next step, you might want to look deeper into some of the control/enable/reset pins on the ROMs, CPU's & PIA's ...
This will show you deeper info about which chips are being held in a certain state to cause the problem.
....and be extra careful when probing around the IC pins, if you short 2 pins together with your multimeter probe, it'll more than likely cause all kinds of grief ;-(
MM.
Tech Tips are brought to you by me, and are aimed to assist beginners and advanced users.
Common sense is sometime so common that everyone ignores it ...
Hurry while stocks last, batteries sold seperately, conditions apply, LMCT 1234.... ;-)
