Hi,
I wanna do simple infrared transmitter circuit together with phototransister.

just simple stupid question: i notice that for normal led, the anode is the long leg (i.e. vcc to resistor and to long leg), while in infrared led, the anode is the short leg :?: am i wrong ?

btw, i found some circuits using opamp for comparator, and some using schmitt trigger inverter, which one is better ? opamp seems flexible as the level can be changed...

 

I have both Regular and Infra-red LEDs. Some of Both Types use the long lead as Anode and or Cathode. Seems there is No Standard.