FLASH LIGHT 7389
The first flashlight was invented by the English inventor David Misell in 1899.
The flashlight had 3 xD batteries that were placed in a tube that acted as the device’s handle.
The batteries powered a small incandescent light bulb and a simple contact switch that turned the light on and off.
A flashlight or torch (UK, Australia) is a portable hand-held electric lamp.
Previously, the light source was usually a miniature incandescent light bulb, but since the mid-2000s they have been replaced by LEDs.
Product model:
Flash light Identical to 7389
Country of manufacture: England
Price: $600
Application:
– Industrial use
– Studio and outdoor broadcasting cameras
Product dimensions:
Includes pin/tip
Base | Diheptal (14 pin glass U14) Side contacts |
Filament | Vf 6.3 Volts / If 0.6 Ampere / Indirect |
Brand name | English Electric Valve Company Ltd. (EEV); Chelmsford |
Tube type | Orthicon |
Origin | UK |
117 x 501 mm / 4.61 x 19.72 inches
An improved version of the 7295 series with a higher target capacitance than the 7295 has improved signal-to-noise ratio and less spurii.
In addition to the diheptal base, it has lateral contacts at the base of the scanning segments.
It is also issued with different qualifications A, B, C… To indicate selection based on different criteria.
Television fluoroscopy became usable only after RCA introduced the “Image Orthicon” 5820 pickup tube in 1945, which added an image multiplier and greatly increased its sensitivity to low light levels. Titled “IO”) was described as “capable of shooting even by candlelight”. It cost about $1,500 at the time and had a lifespan of only 400-600 hours, peaking at about 300-400 hours. Image Orthicon tubes, manufactured by General Electric and the British Electric Valve Company respectively, probably date back to the fifties and early sixties. The photomultiplier section is visible near the base in the GE tube and is hidden in the black part of the English Electric tube.