Peak Indicator (CB20736E)

This circuit triggers an LED when the input signal exceeds the peak, or the value set in RV1. The transistors can be the modern equivalents BC549.

| Clique na imagem para ampliar |

7MHz Transmitter (CB11873E)
This Rytron transmitter was published in a 1953 book. The circuit can be implemented with a BC558...
Phototransistor 2N5777 (CB16044E)
Foto-Darlington for applications such as light sensor. In normal applications only the collector and...
Two-tone generator (CB8446E)
This circuit was found in a 90s Popular Electronics. It generates tones given by the oscillators and...