Generally, you need about 3-4 volts of headroom (beyond the rated voltage of the regulator) to determine if it's working. That's hard to do since most 12v supplies only go to about 14.5v.
The positive regulator should have rail voltage on its center leg. The voltage on its output leg should be about 12v above the positive rail. The voltage on it's input leg should be about 15-20v greater than the positive rail. Check to see if that's what you have.
The positive regulator should have rail voltage on its center leg. The voltage on its output leg should be about 12v above the positive rail. The voltage on it's input leg should be about 15-20v greater than the positive rail. Check to see if that's what you have.
Hello Perry. These are the measurements for the regulators. I triple checked these measurements because it appears that L7812(positive regulator) has negative values and L7912(negative regulator) has positive values. Here are the numbers. L7812 = 1.(Input = -65.63V), 2. (Ground = -71.7V), 3. (Output = -66.4V). L7912 = 1.(Ground = 71.7V), 2.(Input = 67.6V), 3.(Output = 68.7V). Thanks.
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