Cadmium sulfide
Lead selenide
Zinc sulfide
Copper sulfide
0.1MA to 1.2MA
0.2MA to 1.6MA
0.3MA to 2.7MA
0.4MA to 3.8MA
Uni - Junction transistor
NPN - Photo transistor
PNP - Photo transistor
Audio frequency transistor
Amplifier the signal
Converts voltage into current
Produces electrical noise signal
Defects the operation of switching signal
0.5 V
0.8 V
2 V
2.5 V
