Nuvistors and Micro-Modules
June 1959 Popular
Who ever heard of a
"nuvistor?" Not me, that's for sure. If I ever used one, I didn't know about it. There is actually an entry in
Wikipedia for the nuvistor that comports with the information in
this article from the June 1959 edition of Popular Electronics. It was supposed to be a real paradigm changer, but
alas, it never happened. RCA could have made billions off the concept. The other subject of this article on
miniaturization, micro-modules, definitely did gain huge popularity. They are ubiquitous today in the form of
multifunction hybrid modules, plug-and-play system elements, mixed signal ICs with stacked die, etc. If nothing
else, I learned a new word today.
[Table of Contents]People old and young enjoy waxing nostalgic about
and learning some of the history of early electronics. Popular Electronics was published from October 1954 through April
1985. As time permits, I will be glad to scan articles for you. All copyrights (if any) are hereby acknowledged.
Trivia for the day: A nuvistor was used in the
front end of the
HP3400A True RMS Voltmeter (thanks to Michael M. for that).
See all articles from
Nuvistors and Micro-Modules:
New developments in miniaturization
Nuvistors are shown beside their larger glass tube counterparts. Left to right are developmental samples
of a triode, tetrode, and beam power tube. Nuvistors outperform conventional types and make possible smaller, more
efficient electronic instruments.
Two developments which could shape the future of the electronics
industry were recently announced by the Radio Corporation of America. One, a new type of vacuum tube called the
"Nuvistor," comes from the laboratories of the RCA Electron Tube Division. The second, a new technique of
integrating electronic circuits into "micro-modules," was engineered by RCA under a contract with the U. S. Army
The Nuvistor. A new concept in tube design, the Nuvistor is notable for
several reasons. Roughly one-third the size of conventional tubes which perform similar functions, it employs a
unique cylindrical type of construction which is ideally suited for mass production techniques. Materials used are
ceramics, steel, molybdenum, and tungsten. The Nuvistor uses no glass or mica in its construction.
military radio has been made smaller than an average lump of sugar through the use of micro-module
Electrodes are supported from one end in a cantilever fashion. This feature
eliminates the need for mica support discs or spacers. Because of the low mass and shape of the electrodes,
Nuvistors can withstand a high degree of shock and vibration.
Advantages claimed are miniaturization, improved ruggedness, reliability, efficiency, and lower power
drain. Nuvistors operate satisfactorily at temperatures in excess of those possible with conventional tubes.
Another interesting feature is the inclusion of indexing lugs to Simplify insertion into tube sockets.
is expected that Nuvistors will be useful in industrial, military, and entertainment applications. Limited
production will start next year. Future refinements include the possibility of incorporating the cold cathode
design now under development by Tung Sol and the Signal Corps (see POPULAR ELECTRONICS, May, 1959).
Micro-Modules. Developed primarily for military applications, micro-modules are nevertheless expected to
find their way into industrial and entertainment equipment. Seemingly the end step in the trend toward
miniaturization, they are composed of tiny wafers one-hundredth of an inch thick and a third of an inch square.
These wafers, each of which is an electronic circuit component such as a resistor, capacitor, transistor, etc.,
are stacked, interconnected, and encased in a protective coating.
The use of micro-modules makes possible no less than a tenfold reduction in size and weight of electronic
devices. Tests indicate that the tiny cubes should be highly dependable, require little power, and provide high
performance. It is expected that mass production techniques will lower their cost sufficiently to justify a
"take-out-andthrow-away" repair philosophy.
Micro-modules developed to date have all employed transistors. There is no reason, however, say RCA
spokesmen, why they could not be combined with vacuum tubes, or Nuvistors, to offer functions not provided by