World War II Navy Radio
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NOTE - This is a re-creation of Rob Flory's original site which crashed some time ago - unfortunately some photos are still missing but most of the text is here - if you can help with any replacement photos, please send e-mail to Rob or to Nick K4NYW

Click here for Nick's 1950's-60's Navy Radio Pages -

Infrared Signaling Equipment of the US Navy

US/C-3 Infrared Signaling Telescope

A ship in a formation may receive the signal, "Nancy Hanks" by TBS which meant, "Stand by for message by infrared signal light".  The signal was sent by a 12" signal searchlight or 300W train lights equipped with infrared filters that made the signals invisible to the naked eye.  It was received with a US/C-3 infrared telescope.
Bill Henneberry, Chief Warrant Officer USS Trenton, reported to me that his ship was equipped with Nancy equipment in fall 1944 while in the Aleutians.
This link takes you to the Military Electronics page of my website about my grandfather's work at RCA.  He worked on the 1P25 tube and the other hardware used in the telescope:
This link takes you to pictures of my US/C-3 telescopes and servicing them:

Infrared transmitting equipment generally consisted of incandescent lamps with infrared filters.  The higher-powered shipboard equipment used glass filters (Corning 2540), which were rugged and eliminated all trace of visible light.  The handheld lamps such as used on the snooperscope and sniperscope used a plastic (Polaroid XRX) filter.

US/X-12 infrared train light

The US/X-12 Infrared Train light uses a 300-W, 120V bulb.  The filter is made by Corning.

US/X-9 Infrared Beacon

The X-9 beacon uses a 12-volt, 8-Amp bulb in a hemispherical filter.  It is mounted on a 6-foot stanchion.  A control box allows continuous illumination, local keying, or automatic keying with an external keyer.
This seems appropriate for small vessels.


It was recognized that thermal inertia when turning an incandescent bulb on and off, and mechanical inertia when operating a shutter imposed a limitation on sending speed of about 12 WPM with blinking lights and signal searchlights.  Schemes were conceived by which a Cesium vapor tube, with spectral lines at 852 and 894 nanometers, could be modulated at audio frequencies.  A receiver based on a thallous-sulphide cell received the modulated waves and keyed an audio oscillator, allowing sending rates equal to radio, up to the limit of the operator (about 30 WPM).  This technology was working in the lab during the war, but I think it was not deployed before the end of the war.

G.A. Morton and L. E. Flory, "An infra-red image tube and its military applications," RCA Rev., Vol. 7, pp. 385-413, 1946.
Zworykin, V.K. and E. G. Ramberg, "Photoelectricity and its Application," John Wiley & Sons, New York 1949.
J. M. Fluke and N. E. Porter, "Some developments in infra-red communication components, " Proc.  Inst. Radio Engrs., Vol. 34, pp. 876-883, 1946
N.C. Beese, "Cesium vapor lamps," J. Optical Soc. Am., Vol. 36, pp 555-560, 1946.