I apologize for not more completely describing my problem. I'd be glad to send you
a lot more information, if you want to be burdened by it.
I'm using a Sabertooth 2*60 motor driver.
https://www.dimensionengineering.com/products/sabertooth2x60
The issue with erratic operation when connected to the battery charger is not important, I thought it might be diagnostic.
John-