It is a Sony and the display (clock) stays on when the ignition is "on."
The defogger switch is in and works great.  It is illuminated like the dash
lights and the tiny orange  light glows when there is power to the radio.
If I could just figure out how to make the defogger icon look like a radio!
There may be a way to power down the display on some models without going
this route.  FYI, on this switch the big terminals (76H and 76h) are the
12V in and out, the 58b is the dash lighting and the 31? is a ground
connection.

                                                             Jay '85 Westy