Lamps

“Lamp” is the term for any light source used in an electronic circuit. Lamps often look like tiny lightbulbs, but technically the word “bulb” describes only the glass envelope. Additionally, many lamps are encapsulated in a plastic enclosure which can’t accurately be called a “bulb”.

Originally, all lamps were either incandescent or neon glow. Both technologies were initially developed in the nineteenth century. Inside an incandescent lamp, a metal filament is heated to the point that it begins to glow. In a neon lamp, two electrodes are positioned inside an envelope containing neon gas at low pressure. Due to the properties of neon and the positioning of the electrodes, the lamp glows when electric current is applied.

Although LED light sources can also be referred to as lamps, LEDs are typically called “light emitting diodes” in the Wurlitzer records. This terminology reflects the historical distance between LEDs and incandescent and neon lamps. An LED operates according to a more complicated principle than either incandescent or neon lamps, because an LED is a type of semiconductor. Although the basic design of LEDs was developed in the 1920s, practical LEDs did not emerge until the 1960s.

Lamps are often used as pilot lights, which provide visual confirmation that a device is powered on. Although pilot lights play an important role in the aesthetics of the instrument, their primary function is providing feedback to the user. Users can overlook dim or ambiguous pilot lights and forget to turn off the instrument. Because long idle periods are harmful to many electronic circuits, this can lead to the instrument’s failure.