Thanks for the reply.
The battery is fairly new and was at 12.31 Vdc today and the car has net been used for over a week. After starting the alternator was putting out 13.8 V today but the "GEN" light did not go out for about 5 minutes. The "GEN" light staying on after starting is what got me started on this investigation.
The voltage measured at the battery during the start sequence was:
After sitting for 7 days : 12.31 V
With key in on position, head lights come on: 12.0 V
During start : 10.8 V
Immediately after starting: 12.0 V
It took about 15 seconds before the voltage increased to 13.8V
It stayed there even as I changed engine RPM.
"GEN" was on for about 5 minutes then went out. I don't know what the voltage at time was.