Single channel infra-red remote control

1-52 — elektor january 1982 single channel infra-red remote control sing,le channel infra-red remote control Single channel infra-red remote control systems are often used in modelling and for simple circuits in and around the home. The basic requirements for such a transmitter/receiver system are: an uncomplicated circuit which does not use special components and coils; easy construction using a minimum number of com- ponents; screening against ambient light; sufficient range (with or without a focusing lens); low current drain. All the above can be accomplished by using the circuit described here. Technical data Transmitter operating voltage (single) pulse duration carrier frequency peak current Receiver operating voltage operating current (without LEDs) gain range (in line, without focusing Transmitter The circuit diagram of the transmitter section of the remote control unit is shown in figure 1. An astable multivi- brator constructed around two CMOS gates, N3 and N4, oscilla...