In 1943 the War Department contracted with J. A. Maurer, Inc. to make these signal lamps. It's a fully loaded 5 "D" cell flashlight. In the central one degree half angle the candlepower is greater than 3,000 with a peak of 4,500. The beam width for half power is plus 2 degrees to minus 2 degrees, a fairly narrow beam. When you point it up at night the beam is clearly visible.
Can be turned on and off by a trigger or by means of a J-51 hand key and 16 foot cord which operates a relay in the M-227 signal lamp. Can by used hand held either as the plain M-227 or with a rifle type stock using sights on the top. Permanent mounting on the telescoping leg tripod. A Red filter hinges down for use with white light. This is not infrared, but just dark red. The M-172 goggles or MC-430 filters for the M3 or EE binoculars were never part of my set. If you know where I can get them please let me know.
The BA-30 is listed in TM 11-392 as the battery. That was a first generation zinc carbon battery.
Although designed for visual use, I'm sure it also puts out a lot of near and far IR light since it's a filament bulb source.
A modern improvement would be to replace:
- the relay with a MOSFET
- replace the manual keying with digital keying
- the red filter with a near IR filter (no human visible light output)
- the goggles with a silicon based sensor behind a filter matched to the output wavelengths feeding a digital data decoder.
- the bulb with an near IR laser
- the batteries with Li-Ion type
- the receiving filter, parabolic reflector and electronics would be in a parallel tube, like binoculars.
Portovrij? In NL boven € 200,-