codlink:
Sorry, but I don't see any difference in the Ebay ckt to mine. The only thing that I see is that I have a LED and a resistor for the LED on the relay.Also I don't see (nor have I ever seen) pull-up resisitors on the Inputs.
Not trying negative but I would like to understand.
I attached the opto I am using.
The circuit is pretty hard to see for me and I think there is a mistake in it anyway. It looks like the wire shorting out the relay coil shouldn't be there. Notice where the collector of the phototransistor goes and notice that the emitter is not grounded.