Spacistors

Sounds like they're talking about tunnel diodes? They were invented just a few years prior and were used in communications satellites as microwave amplifiers so the timing seems right

Here's what the book says: "Input and output impeances of a spacistor are very high in comparison to the junction transistor" - which seems odd at gigahertz. The diagrams show a 4 terminal device marked collector, base, injector, modulator. "The spacistor eliminates diffusion of carriers through a base region" The modulator is the signal input. Base goes to 0v, and injector to 0v via parallel R/C. Collector is the output. AIUI there is an intense electric field across the input region 60-120kV/cm which ensures fast movement of input current, unlike BJTs.

Basic theory & application of transistors, department of the army 1959. TM 11-690. p239 onward.

NT

Looks like some kind of weird JFET/BJT hybrid where amplification was achieved by directly electro-statically modulating the width of a depletion region, rather than "pinching" a channel

Sounds more like a Gunn or IMPATT diode.

Cheers

Phil Hobbs