Help: I need more power for Frankenstein

Black Matrix

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Hey All,
I bought a Mary Shelly's Frankenstein recently and it has a problem on the power supply board. Simply put, it has no 5 volts dc. It does however have the +12, and -12 that comes from the bridge rectifier. So it has the input voltage to make the +5 if I am reading the schematics correctly. So the bridge rectifier should be working. I also replaced the 2N6057 transistor that makes the +5 voltage thinking it was obviously bad. But still, I didn't get +5 volts. I tried to test every diode and resistor that I found in that circuit on the schematics. All seemed to be close to dead on with the exception of the R6 which was supposed to read .12 and instead read .3. The only thing I didn't know how to test was the MC1723CP which is a programmable Voltage Regulator that uses pulsing DC generated by half of a Bridge Rectifier. Its my understanding that this turns the voltage output up or down and can be programmed from 2 to 37 volts depending on the input. My question is has anyone ever had a similar problem that was caused by a bad MC1723CP (IC1 on the power board). I think it may also turn on the 5 volts as well as regulate it, but I am not sure. Anyone have any advice on the Sega/Data Eastpower supplies (520-5047-03).
And my second question is how exactly is the voltage regulator programmed. Is it done with the surrounding resistors, or is it flashed, or is it linear and depends on the input voltage. Any help would be appreciated.
 
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