Help wanted with digital 220 VAC switch

for home automation project, want 3,7-volt-signal of motion sensor (or arduino) switch on 220-vac-device. on forum, found old discussion http://forum.arduino.cc/index.php/topic,24335.0.html schematic in picture 1. rather new looked safe solution problem. copied circuit in eagle , made pcb (see pictures 2 , 3 below). connected motion sensor, mains 220 vac , 35 ma led-lamp (picture 4). motion sensor on, lamp shining right, expected.

but motion sensor off, lamp blinking frequency of half second. motion sensor disconnected, no digital input, blinking occurs. expected no current lamp without input moc3041 optocoupler. can explain why happens?

thanks!

nope, can't spot fault now, have dangerous blunder in pcb pattern design; have trace passing under moc3041.  should never have trace under optocoupler, in fact pcb should instead slotted under , @ least 5 mm on either end.  trace should instead have been run under r3.

that said, there no obvious answer problem - circuit should work fine; either there defective component (cheap ebay?) or have dirty (wet; conductive) flux between critical points.

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