Blink
After troubleshooting some of the older Gen1 units for no output voltage, I have noticed that some of the voltage regulators, even new ones, seem to work sporadically.  For example, I have had a few that, when the generator starts, the LED light on the vreg does not light up and the generator produces zero voltage.  I turn the unit off, start it back up, and the same vreg then has a lit LED light and the generator works fine.  I have come across this on a few units and can't figure out why.  Any suggestions? 
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Peddler
what most likely is happening is the generator is not catching the field flash the first time due to dirty slip rings or poor field flash voltage.  Ohm out the #4 wire to ground if the ohms are more than 15ohms above the rotor ohm rating you should clean the slip rings.  Also measure the field flash voltage while cranking to see if it is above 8-10 volts.  Lastly sometimes the older VR will simply operate intermittently.
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Blink
Its happening with new vregs too, so I will go with your recommendations..thanks!
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Birken Vogt
Continuous/ignition field boost is the best solution I think.  The newer VRs seem easier to take a flash and take off but some units just have problems.
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