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 of old medical documentation generates pulses in a ratio of 20 to 300 and duration of 3...
This circuit with a supply voltage of only 2.5 V was found in a 2005 Linear Technology...
Microchip Continues Expansion of AVR Microcontroller Product Line with Addition of Three New...