General Electric Sealed-Ignitron Rectifiers
October 1944 Radio News

October 1944 Radio News
October 1944 Radio News Cover - RF Cafe[Table of Contents]

Wax nostalgic about and learn from the history of early electronics. See articles from Radio & Television News, published 1919-1959. All copyrights hereby acknowledged.

Special Insert: Radio-Electronic Engineering Department

"Ignitron" sounds like a contemporary pejorative term for someone who blindly follows orders. In the 1940s, though, it was a type of steel-jacketed vacuum tube manufactured by General Electric for use in conversion from alternating alternating to direct current (AC−DC) power supplies. According to this GE document, "Ignitrons are gas-discharge, pool-type cathode tubes in which the arc is started for each conducting cycle by means of a starting or ignition electrode. The tubes are of the half-wave type in which the current is carried through the tube during only the positive part of the cycle. During the remainder or non-conducting part the residual ionization reaches very low values in comparison with the ionization present in the multi-anode type of pool tube where it is proportional to the load current carried. As a result of the so-called dark, negative half-cycle, the shielding required in half-wave tubes is greatly reduced from that in the multi-anode tube. Reduction in shielding in turn lowers the arc voltages so that tubes of this type may be efficiently applied in the lower voltage (125 to 250 volt) fields. Mercury-pool cathodes are capable of supplying emission currents of may thousands of amperes..." Thus, in that last sentence we know why Ignitrons are no longer used (other than the fact that semiconductors are available to do the job) - the mercury in them would rate them a hazardous device status and therefore be taboo in modern paranoid society in which mercury but "mostly peaceful" riots (er -protests) are considered unacceptably dangerous to public health.

No. 17 In a Series Explaining the Uses of Electronic Tubes in Industry

General Electric Sealed-Ignitron Rectifiers, October 1944 Radio News - RF CafeYou can take d-c power from a-c lines and "spot" it where you need it with G−E sealed-ignition rectifiers

Thy thyratron (left) is the "timer" tube, which usually teams up with the ignitron (above).

The steel-jacketed G−E ignitron is an electronic tube of many uses, and nowhere is its versatility better demonstrated than in converting a−c to d−c economically and efficiently.

Many power-driven machines, such as machine tools, cranes, etc., require d−c power to drive them because of the necessity of the adjustable speed which the d−c motors can provide. The G−E steel ignitron takes a−c from the power lines, rectifies it, and supplies it to the specific locations where d−c motors require it.

Thus, without effect on any other equipment, or on the distribution system as a whole, d−c power can be fed to such diverse machines as drill press, milling machine, power lathe, grinder, and sander. Production is stepped up, and costs, in many cases, are reduced.

The G−E steel-jacketed ignitron tube has no moving parts; is quiet in operation; efficiency is high and practically constant over the entire load range. It can successfully carry severe peak loads.

The ignitron is only one of a complete line of G−E electronic tubes for innumerable industrial jobs. Through its nationwide distributing system, General Electric is prepared to supply users of electronic devices with replacement tubes.

"How Electronic Tubes Work"

This booklet will be mailed to you on request - without charge. Address Electronics Department, General Electric, Schenectady, N. Y.

• Tune in "The World Today" and hear the news direct from the men who see it happen, every evening except Sunday at 6:45 E.W.T. over CBS. On Sunday listen to the G-E "All Girl Orchestra" at 10 P.M. E.W.T. over NBC.

G.E. Has Made More Basic Electronic−Tube Developments Than Any Other Manufacturer

General Electric




Posted April 6, 2021