Section IV
Paragraphs 4-78 to 4-80
arate regulated voltages are used in the audio chassis
dynamotor output is also fed through RC filter R1426
to keep the audio levels constant and to prevent B+
and C1407A and the 230-volt output is used by V1401A
interaction.
as B+ voltage. Voltage regulator V1412, in series
with dropping resist or R1427 across the dynamotor
output, produces a regulated +150 volts for use as B+
4-79. FILAMENT CIRCUITS.
voltage by V1401B, V1402 and V1403. Voltage regu-
(See figures 4-29 and 4-30.)
lator V1411 and R1425 across the 230-volt line, pro-
4-80. The 21-volt output of the line voltage control is
duce a regulated +150 volts for use as B+ voltage by
V1408B. Voltage regulator V1410 and R1424 across
used to energize all the signal generator filaments.
230 volts, produce a regulated +150 volts for use as
Voltage dropping resistors and various series-paral-
Bt voltage by V1406 and V1407. A section of NAV-GS
lel combinations of filaments are used to supply the
switch disconnects V1410 during GS operation, re-
required voltage to individual tube filaments. The r-f
moving B+ voltage from V 1406 and V1407 and dis-
and univerter chassis use r-f filters that prevent rf
abling the 9960 cps oscillator circuit. The three sep-
from entering the filament circuits.
