Two versions of the Eital-McCullough 4W20,000A power tetrode: at left., an early version (1952), cut open to reveal the “bombardment” cathode; at right, one from 1955. This tube is documented extensively in TC for oct. 2010. A very early bulbedd model, possibly the X486 protype, is illustrated on Norm Wilson’s n6jv.com web site. In...
A celebration of the addition of an LRS Relay and ita AEG amplifier to the museum of the University of Electro_Communications in Chofu City, Tokyo. The celebrents are, left to right, Hisashi Ohtsuka (who assembled the collection), Prof. Yukawa (museum curator, Bengt Svensson (who played a mojor role in having the LRS transferred from the...
A group of Eitel-McCullough stacked-ceramic receiving tubes from the “CD” project of the mid-50’s. Details in the article inside. In this issue
A set of classic tube-test labels. See the editorial pages for more details. In this issue
On the Cover Ross Smith’s display of two-digit tubes in the Equipment Contest at Rochester. See p.2 for details. In this issue
A classically styled promotion poster for the Italian tube maker Zenith, with Factory located in Monza. Beginning about 1929, it made a line of European and American- designed receiving tubes. The original art is 10″ by 15-1/2″. It has been reproduced as a lithograph on steel and in a book on old-time posters. In...
In honor of the coverage of cavity-magnetron history in this issue, here ia a classic: the 4J50. This device, with its built-in magnet, was designed by Bell Labs for manufacture by Western Electric during WWII, but successful enough to be offered by at least eight other makers in the US, Britian, the Netherlands, France and...