Western electric 143 a schematic

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Western Hectric Company
No. | 43-A AMPLIFIER

The Western Electric 143A Amplifier is a high quality, medium

gain power amplifier, intended as a basic amplifier for public ad-

dress sound distribution systems and wired program service. It has

two high impedance input connections controlled by a master volume

control; and the chassis has provisions for the addition of pre-

amplifiers and apparatus units for various input combinations.

1 Cha cte cs

3 1 db 50 to 15,000 cycles.

-30 dhm

See Output Power

0 to 250,000 ohms

1.5 to l70ohms

70 volts

52 db from 600 ohm source

Continuously variable

75 watts as supplied with Western
Electric 3508 Tubes in the output
stage, with less than 5% distortion
over the range of 50 to 7500 cycles.
50 watts, 5% distortion, 50 to 7500
cycles when reconnected for 616 Tubes

in the output stage.

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