This circuit is one of many that the reader can find in this section for testing crystals. The circuit uses an indicator LED. Transistor Q1 determines the maximum crystal frequency that can be tested.
This circuit was suggested by Signetics in 1980s documentation. The circuit makes use of the...
We found this guitar effects circuit in a 1997 documentation. As the components used are still...
This FM transmitter has a high power thanks to a push-pull amplifier stage at the output. The coil...