VR1 = 25K
R2 = 1M
R3 = 470K
R4 = 100Ohm
C1 = 47uf/16v
C2 = 4n7
Q1 = VN46AF, BD552
Q2 = BPW34
A transmitter would require a receiver, receiver be applied here serves as an infrared transmitter pair on another page here.
once again its simplicity was obtained with the help of a FET
Infrared light received by the infrared photo diode (in this case BWP34, but other types can also be used) will cause the voltage on R3 varies. this will affect the FET gate and the flow of fiber, so it will be changed to change according to the modulation of infrared rays on the receipt.
This modulation can be heard by using a set of headphones.
This simplicity, of course, have a loss of loss, such as tube lights are turned on in the area around it will be heard as a buzzing sighs.
in a quiet state, the infrared light signal reception is good enough might do at a distance of several meters,
This can be extended with the aid of lenses or other optical equipment.
With some fruit infrared LED and a photo diode, a combination transmitter and receiver dabat you make with ease. This circuit can work well and fit for trial parcobaan.
one more thing. if you want to work well, VR1 should be in sets such that when the diode in the block to light, the measured voltage at the FET fiber will be exactly equal to half the supply voltage.
