This circuit generates a siren sound. It was found in the April 1969 Radio Electronics magazine. The output signal is to be applied to an external amplifier.
We found this telephone amplifier in a European publication from the 1980s. The transistor can be...
In figure 1 we have an application for NLAS5113, a new device from on Semiconductor...
We found this circuit in a Popular Electronics from the 90s. Transistors can be modern...