Pulling my hair out at the moment. I'm not the World's expert on electronics but have been trying to simply copy a design for the following:
How to Make a Laser Alarm | eHow.co.uk
I've followed the 'plan' using a Farnel 970-7808 phototransistor.
The only difference between my unit and the plan is that I've replaced the 12V siren with a mega bight blue LED and 169ohm resistor (intension was to have bank of LEDs once functioning).
Is my trading the LED for the siren the problem or is the diagram faulty?
I've triple checked my work - fairly neat on an IC board and it all seems fine.
Your assistance would be very much appreciated
Thanks
John (UK)
How to Make a Laser Alarm | eHow.co.uk
I've followed the 'plan' using a Farnel 970-7808 phototransistor.
The only difference between my unit and the plan is that I've replaced the 12V siren with a mega bight blue LED and 169ohm resistor (intension was to have bank of LEDs once functioning).
Is my trading the LED for the siren the problem or is the diagram faulty?
I've triple checked my work - fairly neat on an IC board and it all seems fine.
Your assistance would be very much appreciated
Thanks
John (UK)