RCA's (1959) introduction of the Nuvistor vacuum tube, heralded one of the
attempts of tube manufacturers to hold onto a major portion of the
small–signal amplification market. The Nuvistor is a thimble-sized vacuum tube
(enclosed in miniature metal rather than glass)
that promised high-reliability, low-noise, and low-power operation." (All
of which it needed to have any hope of competing in the brave new solid-state
world emerging when RCA introduced it in the 1959.)
Designed mainly for military and test-equipment applications, the
Nuvistor bridged the gap between tubes and transistors. Unfortunately (for
tube aficionados), the release of the Nuvistor appeared at the same time as
the announcement of the first integrated circuit, and its fate was all but
sealed right from the start.
Scott engineers soon replaced Nuvistors in their FM Cascode front-ends
with solid-state FET's (field-effect transistors), achieving another
H.H. Scott FM (RF) tuner front-end applications that use these tubes:
DESIGN, April 15, 1959, p. 3)
"Tube manufacturers have unveiled, in recent weeks,
drastically new concepts and techniques aimed to keep them in the race with
the transistor industry. Smaller than a thimble, more rugged and efficient
than present tube designs, and particularly suited for mechanized
production, the "Nuvistor" represents a radical departure in the
electronic-tube concept. Developed by the RCA Electron Tube Division, triode
and tetrode versions have already been demonstrated in TV tuners reduced to
one -third the volume of conventional TV tuners."
(From an RCA press press release):
"Although transistors are still a "natural" for many
low-level applications, the Nuvistor does provide certain significant
* Nuvistors, being in the tube family, are high-impedance devices --
circuit components are generally less expensive.
* Lower noise figures and higher frequency operation are obtained.
* Tubes can handle momentary overloads while solid state devices
generally will burn out.
* Stable operation is possible with Nuvistors over wide temperature
ranges (-190 [degrees] C to 350 [degrees] C).