Series Crystal Butler Oscillator (CB25557E)

This circuit was described in an article in the February 1993 Radio Electronics magazine. The frequency depends on the crystal and L1 is optional.

| Clique na imagem para ampliar |

Automatic Polarity Switching Voltmeter (CB14856E)
This circuit automatically inverts the test leads connection according to the polarity of the...
Volume Control (CB19186E)
This circuit was found in a publication from the 90s. The circuit can be assembled with modern...
Word Filter (CB13612E)
This filter, from an audio publication from 1977, passes the frequency range corresponding to the...