WEBSTER CHICAGO 79 - Page 21

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•VIEMISTER

.t.

CHICAGO

BULLETIN

79P038

MODEL

80

1 —

The

neon

volume

level

indicator

circuit

has

been

added

to

simplify

maintaining

a

proper

recording

level

without

the

use

of

an

external meter.

2 —

The

bias

circuit

of

the

6S17

has

been

changed

to

the "

contact

potential"

circuit

for

stability

and

simplified

production.

3 —

The

values

of

resistors

No.

R-3

and

No.

R-7

have

been

changed

to

the

values

indi-

cated

on

the

schematic

to

reduce

sensi-

Fig.

26—

AMPLIFIER

CHASSIS (

TOP

VIEW)

tivity

and

the

probability

of

trouble

with

microphonic

tubes.

4 —

Condenser

C-12

has

replaced

the

blue

lead

from

terminal

No.

3

of

the

6V6

socket

to

the

oscillator

coil

and

the

red

lead

from

the

center

top

of

the

oscillator

primary

has

been

removed

from

terminal

No.

4

of *

the

6V6

socket

and

grounded.

This

removes

DC

from

the

oscillator

coil

and

prevents

speaker

burn-

out

if

the

oscillator

should

ground.

18