Vehicle horn of vehicle horns are used by percussionists as sound effects, or even melodically, in musical works. For example, George Gershwin's 1928 orchestral work "An American in Paris" calls for the use of 4 taxi horns. György Ligeti's opera "Le Grand Macabre" features two "Car Horn Preludes" scored for 12 bulb horns, each one tuned to a specific pitch. Klaxon is a trademark for a brand of electromechanical horn or alerting device. Mainly used on cars, trains and ships, Klaxon horns produce an easily identifiable sound, often transcribed onomatopoeiacally in English as "ahoooga." Like most mechanical horns, the klaxon has largely
Registered jack models require additional power (~6 V AC) for operation of the incandescent dial light. This power is delivered to the telephone set from a transformer by the second wire pair (pins 2 and 5) of the 6P4C connector. RJ21 is a registered jack standard using a modular connector with contacts of up to 50 conductors. It is used to implement a 25-line (or less) telephone connection such as that used in the 1A2 key telephone system. The miniature ribbon connector of this interface is also known as a 50-pin telco connector, CHAMP(AMP), or "Amphenol" connector, the latter being a genericized