This circuit was sent to me by Mr Guy Bocquillon from France. Now retired, and in his seventies, Mr Bocquillon keeps himself active in his hobby and his results and support are most appreciated. The notes on the schematic are in French as Mr Bocquillon’s English is not too good.
After building both my Mark 1 and Mark 2 circuits, Mr Bocquillon has made an improved version, which is working very well. His design
is based is based on an active filter, centered at 37KHz modulating frequency and uses a photodiode and op-amp from Texas Instruments.
Mr Bocquillon also says that after plenty of tests for his pleasure (because my job is became my hobby) he has made this circuit which is working very well. It is just necessary to built a shield around D1 and IC1/IC2 to avoid risks of oscillations around 37kHz.
I would like to point out that this circuit will also work with any other appliance using 37kHz as the IR modulating frequency. The original artwork was done in MS Paint, and as you can see is a very capable circuit.
I will be releasing some schematic components I have made for Open Office Drawing program later this year onto my site. These can be used to draw schematics and will be available in colour for clarity.