Radio with amplifier (CB20486E)

We found this circuit in a publication of 1991. The audio amplifier is an operational that admits equivalent.

Rectangular Generator With Active Cycle (CB10492E)
This circuit is from a 1998 Electronics Now and can be easily assembled since it uses a common...
Incandescent Lamps VU Meter (CB17345E)
This circuit triggers three incandescent light bulbs following the audio signal applied to its...
DC multiplier LM339 (CB15190E)
This circuit was obtained in the SGS manual of linear integrated circuits of 1982. The components used...