Consult paragraph 5-5:
http://www.rigpix.com/hallicrafter/sx117_manual.pdf

73's
Richard Clark, KB7QHC

Dick,

you read my question too quckly. I was not referring to the electrical
adjustment (there is a potentiometer just for that) but to the mechanical
adjustment.

In a properly maintained radio, the meter should stay at zero even when the
radio is off. That is the reason for the mechanical adustment.

73

Tony I0JX