Lately I receive the Weekly Newsletter "Ray's Computer Tips" as Spam in my Gmail Spam Box. Is there any thing to do to change that?

Not that I know of.  You could ask Gmail why they are listing valid emails as spam.

Ray, thanks for the tip.

Gmail suggests:
1.     Create a filter (you can do this while reading the message in question: click the down-arrow next to the Reply link, and select 'Filter messages like this' from the menu).
2.     Enter the information of the messages that are being improperly labeled as spam (e.g. the sender's email address).
3.     Click Next Step.
4.     Select the checkbox next to 'Never send it to Spam.

Or:  Put the senders address (rayscomputertips@regvac.com) in your contacts list.

   Good, thank you.

   So, anyone receiving Ray's Computer Tips as spam on Gmail accounts can follow elicarmel's instructions above.  Other email providers may have similar procedures.