Transistorization of Nuclear Counting Circuits

The advantages of long operational life, low-power drain and miniaturization may be realized in nuclear counting circuits through the use of transistors. The disadvantage of instability, due to the effects of temperature change in the transistor, may be minimized in counting circuit designs. The predominant effects are a change in the grounded emitter current gain (beta) and a variation of the leakage current through the transistor (Ico). The binary circuit is analyzed for stability criteria, and may be tested conveniently through a simulation of Ico for the maximum operating temperature. Representative circuits of a binary stage, amplitude discriminator, one-shot multivibrator, and ratemeters are included. These were designed using the criteria of a minimum Beta and a maximum Ico.