Junction Transistor Blocking Oscillators

Blocking oscillators are useful as generators of rectangular pulses. Though junction transistors with alpha cutoff frequencies of a few megacycles have been most frequently used for low-frequency applications, they make surprisingly fast blocking oscillators. Rise times shorter than 0.1 microsecond have been analytically predicted and experimentally obtained. A simple but experimentally verified analysis indicates the proper transformer design for best rise time and prescribed pulse width. Using extensions of the primary results, one can evaluate triggering requirements and the effect of loading on the oscillator performance. Experimental results support these extensions.