VHF Pulse Techniques and Logical Circuitry

Techniques and components for use in systems handling pulses of 10-millimicrosecond width have been investigated. Bandwidth requirements have led to the use of secondary emission pentodes in amplifier service. The limitations of time delay in feedback type circuitry have made necessary the use of special logical reshaping circuits. A test program on commercially available semiconductor diodes resulted in the selection of high-conductance, goldbonded junction diodes for use in switching circuits. Multivibrator circuits have been designed for gating and delay functions. Electromagnetic delay lines of both the coaxial and helical-wound types have been used for delay and for pulse generation. These components have been applied to the design of an arithmetic unit which performs binary addition, multiplication, and dynamic storage at a pulse repetition rate of 50 megacycles per second.