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.
We found this circuit in a 1997 documentation. Its purpose is to fan an inverter for fluorescent lamp...
We find this circuit in a 1994 technical documentation. The circuit has a 12 V input and a 33 V...
In the figure we show how two diodes can be used to simulate the center tap of a push-pull driver step....