mcr switcher and interconnect cable help.

cleverlyj

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i have a question about the mcr switcher kit and mcr interconnect cables as well... (satan's hollow)

my +5 is set at 5.1 at the switcher and with it set there the +12 reads at 12.31. testing the voltages at the game board at connector J1 on the cpu board, the +5 reads 4.94 where the +12 still reads the same.

my concern is that if i adjust up the +5 to get it to read 5.0-.1 at the game board, the +12 will go up as well, and read closer to 12.4 or so (i've tried).

anyways, is that ok to have the +12 that high? (i.e. 12.4) or will it cause problems?

i do have new interconnect cables on order and will be replacing them as soon as they're delivered. is it best to wait to do anything until the cables are replaced first, as the ones i have are crappy looking and coming apart, or is it ok to adjust the p/s now and have the +12 reading at 12.4?
 
ok. and having the +12 a little high like that (12.4) is ok on both reg and unreg +12 lines?

now, is a .15 voltage drop on the +5 ok as well, and should the +12 typically move when you adj the +5 on a switcher or should it normally stay the same?

and finally, is it better to adjust these after i replace the mcr interconnect cables, or will that most likely not have any affect on the voltages?
 
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don't worry about the 12v- its just used to power the audio output usually.
The +5 runs the logic, and if its too low, then you'll have all kinds of problems.
If your going to replace the interconnects, i'd check the voltage afterwards just to be sure.
Now, on mcr games, you really should check the +5 at one of the eproms on the board itself. The ssio is the top board, any one of the eproms is fine - adjust it until you get exactly 5 volts on an eprom, and you'll be right where you need to be. Incidentally, eproms and ttl logic chips both have the ground as the bottom left pin, and the +5 (or Vcc) as the top right pin (with the notch facing up).
 
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