UPDATE:
Today, both the power company and an electrical contractor were out. The power company lineman installed a monitor at the lines feeding my house. They will monitor it for approximately a week to determine the cause of the voltage drop.
A bit later the electrical contractor also came out. I contracted with him to replace the entrance service, from the mast, to a new meter plug, and a complete replacement of the main panel, with an upgrade to a 200 amp service. They are also going to install a surge suppressor in the new panel. The surge suppressor also includes a $75000.00 rider for my home owners insurance.
For those who worried about me attempting to do this on my own, I am ever thankful for your concern. I think it was in a Dirty Harry movie - "A man's got to know his limitations." Well this one certainly was above my limitations, and both the wife and I are feeling good about this investment in our lives.
Once again, thanks to everyone for your answers, input, and concerns. It's what this forum is about for me.
bob