A quick circuit challenge
My furnace has shut off twice overnight in the midst the middle of an artic freeze here in the North East US.
I'm trying to build a very quick circuit that will detect the light from a red LED and sound an alarm. I am unable to get at the pins of the LED and thus need this Red LED light sensing alarm. I already have a cheap water alarm that when the water touches two contacts the alarm will go off. But the Burner LED flashes three times then repeats, thus I need a latching on circuit preferably.
Any ideas.
The current thru the LED is more than likely about 20mA and the voltage is probably 2V or less!
Opto Sensors I have available...
http://www.alliedelec.com/Images/Pr...PTO-PRODUCTS_ACTIVES-AND-PASSIVES_2760052.PDF
http://www.datasheetcatalog.org/datasheet/vishay/81519.pdf
http://www.alliedelec.com/Images/Products/Datasheets/BM/HONEYWELL_OPTO_PRODUCTS/276-0029.PDF
My furnace has shut off twice overnight in the midst the middle of an artic freeze here in the North East US.
I'm trying to build a very quick circuit that will detect the light from a red LED and sound an alarm. I am unable to get at the pins of the LED and thus need this Red LED light sensing alarm. I already have a cheap water alarm that when the water touches two contacts the alarm will go off. But the Burner LED flashes three times then repeats, thus I need a latching on circuit preferably.
Any ideas.
The current thru the LED is more than likely about 20mA and the voltage is probably 2V or less!
Opto Sensors I have available...
http://www.alliedelec.com/Images/Pr...PTO-PRODUCTS_ACTIVES-AND-PASSIVES_2760052.PDF
http://www.datasheetcatalog.org/datasheet/vishay/81519.pdf
http://www.alliedelec.com/Images/Products/Datasheets/BM/HONEYWELL_OPTO_PRODUCTS/276-0029.PDF
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