Simplest LIRC alsa-audio receiver

I see simple way for receiving and testing IR remote here:
http://www.lirc.org/ir-audio.html

But there is even simpler receiver, containing only 1 element!
All computer microphones are electret type. They need power to work and in computer microphone input there is provided power just as in this image:

This power is enough for usual infrared photo-diode to work.
I made simple jig with one photo-diode and audio jack to plug in microphone input in computer. This is the schematics:
diode_schematic2

Dependent of used photo-diode it can receive signals from up to several meters.
This receiver due his simplicity have no filtering or frequency selection and his immunity to noises and external interferences is almost zero!
I used it for IR remote signals recording and set-up of LIRC control files.

And how it works:
diode_schematic
Photo-diode changes his resistance when it is lighted by IR remote. This change diode and resistor current. On resistor appears voltage change which is fed to sound card input through DC blocking capacitor. In result following waveforms can be seen when use sound recording software (for example Audacity:
samsung_ir

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