Infrared modulated transmitter (CB7247E)

This simple Philips circuit from the 1960s can use any general-purpose transistor. The signal is modulated at 2.7 kHz.

8 W amplifier TDA1908 (CB15226E)
The supply can be between 4 and 10 V in this circuit and R4 is necessary when the supply is less...
1 to 4 W amplifier TDA1015 CB15972E (CB15972E)
This is an integrated recommended for portable amplifiers, recorders, and battery powered radios. It...
Linear sawtooth generator (CB7802E)
Found in American documentation, this circuit generates linear sawtooth signals using a constant...