This filter with the 741 op amp was found in the February 1995 Electronics Now magazine. The power supply must be dual.
With the circuit in the figure, it is possible to control the amount of heat generated by the...
We found this circuit in an old European documentation. Transistor TR1 can be BC548 and TR2 can be...
This small telephone transmitter uses a telephone capsule as a microphone. The L1 coil has 4 to 5...