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Imaging Tubes

Dumont 3ABP2
	The 3ABP2 is a two-gun electrostatic deflection CRT, capable of projecting two beams at once. The tube's 3-inch screen is coated with a high persistence green phosphor. Though the separate guns share a common heater, each gun has it's own set of deflection plates and can be independently positioned. [View Detail]

Futaba TL-3508XA

Back in the time before LEDs, large outdoor displays like the 'Jumbotrons' seen in many stadiums had to rely on tube technology for their displays. The Futaba TL-3508XA flood beam CRT shown here is a rare example of this quite unusual technology. The flood beam CRT differs from a normal CRT in that the electron gun within does not produce a focused controllable beam. Instead, electrons are sprayed in a wide cone across the entire front of the phosphor screen, effectively turning an image display device into a simple light bulb. The TL-3508XA actually contains multiple flood beam devices in a single envelope, enough to display eight pixels of RGB data. A control grid sits in front of each electron gun, allowing the intensity of each pixel to be varied by a low voltage control signal. Thousands of tubes such as this are required to build an entire Jumbotron display. Tubes were assembled into modules like the Sony A-6279-869-A, which had quick-connect fittings for easy removal. Tubes such as this only had an operational lifespan of around 8000 hours, a means to quickly replace and remove dead display elements was mandatory. The A-6279-869-A modules are equipped with plastic shade bars to increase the contrast of the display. [View Detail]

IEE BA-0000-P31

IEE's rare foray into the world of numeric display tubes, the 'Nimo' display is a very special variant of the common cathode ray tube. A Nimo tube contains an array of 10 electron guns, each with a digit shaping mask, which are aimed at the center of a phosphor screen. Activating a particular gun will cause the given digit to appear on the surface of the screen. Number's displayed on a Nimo tube are crisp and much more visually appealing than other display tubes, but the phosphor coating on the face of the tube can easily become burned-in after prolonged use. Worse, Nimo tubes require a 3000 volt anode supply as well as a 1 volt power supply for the filament, which makes them much more difficult to work with than other display tubes. The 3000 volt supply connects to an anode stud that exits the side of the tube envelope, a special socket was supplied by IEE to make this difficult connection. [View Detail]

Telefunken XM1000

Telefunken's XM1000 cathode ray numeric indicator was the European competitor to the IEE's Nimo devices, which are covered above. The XM1000 is smaller than a standard single digit Nimo tube, but is contained within an oval envelope that allows for tighter side-by-side installation of multiple tubes. The XM1000 contains twelve electron guns that are projected through shaped masks to display numbers on a phosphor screen, which allows for the display of numbers as well as left and right decimal points. As with the IEE devices, the XM1000 requires an anode voltage of several thousand volts to function, this is delivered through a clip connection on the side of the envelope. [View Detail]

RCA 913
	The RCA 913 is an electrostatic deflection CRT with a tiny one inch screen. This octal base tube has a curved spherical screen and an unusual metal shell, instead of the glass neck seen in most CRT's. The 913 was specifically targeted at the hobbyist and experimenter market, and had a selling price of $4.00 in 1936. [View Detail]

RCA 7038

A vidicon tube is a sort of 'reverse CRT'. Instead of sweeping a beam of electrons across a phosphor coating to display a picture, vidicon tubes sweep an electron beam across a photosensitive target to generate an image from the light striking the target. The 7038 is a fairly standard vidicon tube, with a length of 5.6 inches and a diameter of 1.1 inches. Vidicon tubes are still used today in some security cameras. [View Detail]

RCA 6499

The RCA 6499 is an unusual type of data storage tube called a Radechon, first produced by RCA in 1956, and used in such venerable systems as the SAGE defense computer. The 6499 uses an electron beam to store data on a charged target. Much like modern PC DRAM, the contents of memory must be continually refreshed in order to be maintained. The 6499 has a maximum storage capacity of 16,000 random-access bits, though its practical capacity is somewhat less, due to splatter on adjacent bits from the electron beam. [View Detail]

National Union 122P11
	One of the smallest CRTs we have ever seen, the 122P11 has a a screen diameter of only 0.75 inches. [View Detail]

EMI 'Tabby' CV144

The CV144 is an infrared image converter developed for military night vision applications during World War II. Surplus tubes later made it to the commercial market and were utilized in infrared monoculars and other similar devices. The CV144 is part of a series of tubes (CV142-CV149) which were all manufactured as the same part, individually graded during inspection for their maximum operational voltage, then assigned a part number accordingly. CV144 is the most typical grade. [View Detail]

Matsushita M03JHB9WW
	The M03JHB9WW is a typical camcorder viewfinder tube from the early 1980s, a black and white television CRT with a tiny diagonal screen measurement of only 1". The example pictured here is equipped with an equally tiny deflection coil. [View Detail]

Matsushita S4097A
	Vidicon-style camera tube. [View Detail]

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