tony ennis
New Member
I pulled what I think is a phototransistor out of my junk bag.
It's a small clear flat rectangle with 3 leads.
I hooked it up with +5v on one leg, and an LED -> 100 Ohm resistor -> gnd on the other. The LED came on when I applied the power. I covered the phototransistor completely and the LED didn't go out.
I didn't hook the middle lead up to anything.
The guy that gave me the bag o' parts thinks the phototransistor is a PN116PA or PNA1605F. I can't find a datasheet.
I'd like to make a circuit that if the phototransistor is cut off from light, the LED goes out. I think what I have would do that if I understood how the phototransistor worked, especially the middle lead. Any hints?
It's a small clear flat rectangle with 3 leads.
I hooked it up with +5v on one leg, and an LED -> 100 Ohm resistor -> gnd on the other. The LED came on when I applied the power. I covered the phototransistor completely and the LED didn't go out.
I didn't hook the middle lead up to anything.
The guy that gave me the bag o' parts thinks the phototransistor is a PN116PA or PNA1605F. I can't find a datasheet.
I'd like to make a circuit that if the phototransistor is cut off from light, the LED goes out. I think what I have would do that if I understood how the phototransistor worked, especially the middle lead. Any hints?