Page 10 of the Service Manual says (8) Band select/allocation change button (-BAND-ALLOCATION) Press to select the MW, LW or FM radio band. Press and hold to change the MW frequency step.
http://diagramas.diagramasde.com/audio/Technics%20sa-ch655a.pdf
I could not be bothered to research the other things you asked about.
Good Luck...
January 2016
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