JRC

            The Japan Radio Company, or JRC, to use its present-day name, has one of the longest legacies in the maritime electronics domain. From its corporate roots in radio telegraphy, in 1915, it began the first maritime weather service in the region around 1922, and by 1939 it was experimenting with the manufacture of 500-Watt, 10-cm wavelength cavity magnetrons. Possibly JRC's designs resulted from exchanges with Telefunken, in Germany, with whom JRC had a formal arrangement on technology sharing and where Dr. Hans Hollman's work on magnetrons was well known. Dr. Hollman lectured widely, and observed that 'at every table where a light was on, a Japanese student was busy taking notes' (from anecdotes provided by his grandson, Martin Hollman, to the authors). Equally, the JRC designs may have grown from early work by engineering student Kinjiro Okabe, who had developed a 10-watt 6-cm split-anode magnetron in 1926. In any event, it appears that JRC may have been among the first industrial organizations to attempt manufacture of magnetrons.

            Postwar recovery started in the field of acoustics and ultrasonics; by 1950 the company had commenced manufacturing meteorological radars, and its first marine navigation radars entered production in 1952. Some of its designs presumably benefited from an informal partnership it struck with a US company, Raytheon; even so, it can claim many national 'firsts', ranging from micro-miniature electronic components to space-based communications and navigation systems.  It has remained active, ever since it released that 1952 product, as a rare and possibly unique example in the MNR domain: as 'New JRC', it manufactures its own magnetrons and many of its microprocessor components, continuing its early manufacturing legacy; wherever magnetron data could be found for other MNR manufacturers described in this handbook, the devices appeared to originate either from EEV, a division of Marconi that does not manufacture radars, or from New JRC. Equally unusually, the company logo has remained essentially unchanged since it was introduced in December 1945.

            Today's product line comprises systems ranging from some of the smallest radome-based designs for power-boats and service craft, to some of the largest and most powerful systems afloat - not by any means as complex a catalog as either of its Japanese competitors, but only because it appears to engage less in the 'mix-and-match' methodologies of Furuno and Koden. In general, its published documents show a fairly close coupling of antennas and scanners, with rarely more than two antennas associated with any given system. It had also not, as of October 2006, made any substantial move into either 'RadarPC' or 'black-box' architectures; its only such design, the radome-based JMA-5104, is intended for below-decks operation in power-boats. Nor does its documentation reveal any implementations for high-speed craft, an omission that may be more 'as documented' than factual. So, the characteristics of the JRC inventory may be substantially more varied than the published record indicates. Documentation of this inventory is split, for ease of presentation:
 

Appendix 3, available only to subscribers, is dedicated to describing the JRC systems held by the Naval Research Laboratory.

Appendix 1 Physical Characteristics

Appendix 2 Transmission Characteristics

Appendix 3 Observed Behaviors