TM 3-6665-209-35
2. Solder the marked wires leading
3. Solder the marked wires leading
to the selector switch S8 (17) to
to the interval timer M1 and the
their
respective
switch
test cycle timer M2 to their
terminals. Refer to the wiring
respective terminals. Refer to
diagram (fig. 2).
the wiring diagram (fig. 2).
(g) Power transformer T1.
1. If the two rods (12, fig. 12) were
Note
removed, install the two rods on
the top of the electrical chassis
Two
electrical
wires
are
not
(13) and secure them in place to
connected to the interval timer M1
the
chassis
with
two
until the electric chassis assembly is
lockwashers (14) and screws
installed on the chassis assembly
(15).
(TM 3-6665-209-12).
2. Position the power transformer
T1 (8) on both rods (12) and
(5) Installation. Install the electric chassis
secure it in place with two
assembly to the chassis assembly as
lockwashers (10) and screws
described in TM 3-6665-209-12.
(9).
3. Connect the two transformer
25. Calibrator Assembly
wires previously removed from
the terminal board TB1 (20) to
a. Description and Function.
The calibrator
terminals 2 and 3 of the terminal
assembly (fig. 14), a subassembly of the chassis
board by tightening the terminal
assembly, is used to calibrate the indicator. It consists
screws. Solder the remaining
of a diaphragm (5), calibrator plate (4), calibrator
wires to the terminals of the
housing (8), calibrator bracket (16), needle assembly
power transformer T1. Refer to
(15), contactor needle bushing (12), contactor insulator
the wiring diagram (fig. 2).
(13), worm (24), worm shaft (21j, spring (22), two
(h) Keying relay K2.
crosses (2 and 40), two plug cocks (43 and 45), stop
1. Install the keying relay K2 (7,
shaft (25), and associated hardware. By loosening the
fig. 12) on the top of the
shaft lock (37, fig. 3) and turning the knob (6), the worm
electrical chassis (13) and, from
shaft (21, fig. 14) is rotated imparting motion to the
the bottom of the chassis,
needle assembly (15) through the worm (24). As the
secure it in place with two
needle assembly turns, the silver contact on the end of
lockwashers (3, fig. 13) and
the needle assembly shaft moves toward or away from
screws (2).
the silver button soldered to the center of the diaphragm
2. Solder the marked wires leading
(5) depending on the direction of rotation of the
to the keying relay K2 to their
CALIBRATE knob. The amount of gap "set in" between
respective terminals. Refer to
the silver button of the diaphragm and the silver contact
the wiring diagram (fig. 2).
of the needle assembly is always small. Therefore, only
(i) Interval timer M1 and test cycle
a small amount of rotation of the calibrate knob is
timer M2.
necessary to move the needle assembly and close the
1. Place the interval timer M1 (1,
gap. Calibration procedure of the indicator is described
fig. 12) against the test cycle
in TM 3-6665-209-12. During use of the indicator, the
timer M2 (5) and secure the
amount of gap existing between the silver contact of the
housings of the two timers
needle assembly and the silver button of the diaphragm
together with three screws (4),
depends on two things: first, the setting as "set in" and
lockwashers (3), and nuts (2).
second, upon the pressure differential on both sides of
2. Position the four spacers (6) on
the diaphragm. The calibrator assembly is sensitive to
the top of the electrical chassis
the amount of pressure or vacuum applied against the
(3) and position the housing
diaphragm. Elsewhere from the indicator, while in use, a
which contains the two timers
measured amount of air (pressure or vacuum) is directed
on the spacers. Secure in place
to the
with
four
screws
(23),
lockwashers (27), and nuts (28).
AGO 8069A
35
