I found a picture of a power supply
This brings me to another question seeing the circuit attached inside the battery compartment.
Mine does not have that one except there are holes where it could be attached.
My question, -- There are holes in the front lid, what are they for?
Are they for a card with instructions for use?
I have scoured the WWW for an open photo, but always they have the book displayed, covering up any writings that may be attached there