An Unconventional Loudspeaker system
Latest
change 2019-01-16
Power board
The
Power Board switches mains power to the PSU and provides
an indication signal MAINSOK.
For this board no real PCB has been designed, the Eagle
board file has been routed but that is used only for
hand-wiring the board.
Schema
The
operation is quite self explaining.
The solid-state switch D2W202F switches only on
mains voltage zero crossings which helps limiting
the rush-in current.
The neon indicator should have a built-in series
resistor. 220 kOhm is usual for 230 VAC.
The optocoupler should work well with 1 mA input
current. The arduino input on the FLT board has an
internal pull-up of some 10's of kOhms, so you
wo'nt even need a very high CTR type.
Layout
If one ever should make this to a real PCB use much wider
traces so it might survive an accidental short circuit in
the mains circuit.