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At 06:27 PM 5/18/00, Christopher X. Candreva wrote:<br>
<blockquote type=cite cite>On Fri, 19 May 2000, Paul Sommers wrote:<br>
<br>
..<br>
Oh -- here's my pearl of wisdom: If a board isn't working, consider any<br>
previous repair work suspect. If they other guy knew what he was doing, the<br>
board would be working.<br>
<br>
-Chris</blockquote><br>
<br>
Might I suggest that you consider the quality of the work previously done before you blame the previous person? Often boards (like cars, etc) have many potential causes of failures, however if the repair job before is covered in jumper wires from damaged traces, well then you should certainly verify that work. On the other hand there can be bad IC sockets, battery leakage problems, voltage surges-static electric shock, power supply issues, and any number of reasons why the game has failed....The best way to look at service is to have the attitude that this worked once, and lets now itemize what is NOT happening: <br>
1) check for good power (no AC ripple) and correct voltages. <br>
2) is the MPU receiving the correct RESET signal? <br>
3) is there activity on the address and data buses? (Logic Probe or voltmeter)<br>
4) are the IC sockets good-do they seem to really clench the IC firmly? Reseat all ICs.<br>
5) can you verify the program?<br>
6) are the dip switches set correctly?<br>
7) if a multi-board, are the cables plugged in? Reseat all cables.<br>
8) and on and on....<br>
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Received on Thu May 18 20:01:00 2000
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