This circuit is from a 1977 Signetics integrated circuit manual. The output transistors can be BD136 and BD237 and the symmetrical supply can be from 6 to 12 V. The voltage gain is 10.
In the circuit of the figure, when pressing S1 the sound varies according to the value of R2 and...
May 2017 - The new ROHM SFR series anti-sulfur resistors can now be obtained from Mouser...
Suggested by General Electric documentation from 1968, this circuit activates a relay after 60...