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Thursday, January 3, 2008

Wireless IR headphone transmitter


Audio input from PL1 frequency modulates the VCO section of a 4046 PLL chip. The VCO output drives Q1, a switching transistor. Q1 drives two IR LEDs. The signal produced is around 100 kHz, FM carrier VCO sensitivity is around 7.5 kHz/V.

1 comment:

Unknown said...

Hi! Big fan of your blog..!!

I was wandering if a Stereo version of the Wireless IR Audio headphones (transmitter and receiver) was possible? Would be interested in the schematics. All links on the net seem to be dead!

Great Site. Keep up the great work.