Western electric 117 a schematic

Page 2

Wemm Electric Company

No.| I7 -B AMPLIFIER

I la! AMPLIFIER

'/A SLOT "A: DEEP
(STDV RELAY RACK MIG.)

3 1G. X 2 WIDE CUYOUT IN
CABINET TO CLEAR SWITCHES.
PROJECTION 0F SWITCHES yo.

'A KNOCKOUT
EACH END
IV. NOLES

SUMMARY OF TYPICAL CHARACTERISTICS

Circuit Diagram . . .ESXX»614196
Wiring Diagram t ESR-614197
Gain at 1000 Cycles. ,, .. ,, V. r, .82 I 2 db for 30 ohm source and 600 ohmload
85 I 2 db for 250 ohm source and 600 ohm
load
Source Impedance. . r , . ...Nominal 30 or 250 ohm impedances
Internal Input Impedance . High With respect to nominal source
impedances
Load Impedance ,, .H. . . . 7 Nominal 600 ohm load
Internal Output Impedance. Approximately 170 ohms
Output Level . . ., V +20 db volume limiting, +25 db Without
(Max.Single Frequency) volume limiting with approximately 5 per
cent total harmonic distortion
Output Norse Level . . .7 732 db unweighted; -42 db with program
(At Max. Gain) noise weighting
Frequency Characteristic ,. . Useful frequency response $540,000 cycles.

Flat within 1 1 db from 35 to 10,000 cycles.
See ESA«746167

Power Requiredr V M 105-125 volts, 5060 cycles, 50 watts

Fuse ., r ,7 r 7 Circuit fused for 6/10 ampere

No. of Mixer Channels 7 .From 1 to 4-1168 Amplifiers may be used
with each 117A Amplifier to furnish from
1 to 4 mixer input channels

Master Gain Control.....,...... 7, mGaIn control either local or remore achieved
by varying bias of variable mu tube
Mixer Gain Control, . ,. r Gain control of 116B Mixer Amplifier

achieved independently by varying bias of
variable mu tube at either local or remote
position

Expandor Characteristic, .V.,.Expansion ratio 11/211

Output Limiter Characteristic Output limited to +20 db for input levels as
high as -22 db

7102,