Quote Originally Posted by flotulopex View Post
Dave,

Why do you think a phototransistor is "complex"?

I connected it just like you show it up in your webpage and it works. I have connected a BC237 to amplify the phototr's signal but this doesn't make it more reactive.
How are you measuring/detecting the output?

With a phototransistor you will receive the carrier frequency, usually in the 36-40kHz range. It's difficult to measure the amplitude of a 25-28µS pulse and the output of the phototransistor circuit will be a series of bursts at the carrier frequency. You'll have to count the number of such pulses to determine the duration of the bursts and decode the transmission. Or, you'll have to use a low pass filter to demodulate the signal to recover the data envelope.

An IR receiver demodulates the transmission and outputs the baseband data envelope with the width of the spaces (it's active low) proportional to the duration of the bursts. It's an order of magnitude or two simpler to deal with.

I suggest the TSOP1100 (available from Mouser) because you don't have to worry about matching the carrier frequency of the IR remotes you might come across. Read the datasheet for the TSOP1100 - it's got a lot stuffed into that small package.