Starting Control Systems

pitch transmitter is fed to a control transformer (B 14)

3. Turn the master switch to the ON position. The

mounted on the master compass and meshed with the

green ship's supply 400-Hz power green lamp should

pitch gear. The output signal from the control

light at this time to indicate that power is available.

transformer (B14) represents the amount of pitch error

The voltage regulator green lamp should also be lighted.

in the roll-pitch phantom. This error signal is fed through

The compass control and follow-up alarm lamps on the

the pitch follow-up or servoamplifier to the pitch

panel will be lighted either red or green. Now, wait

follow-up motor, which positions the roll-pitch phantom

for the blue ready lamp located on the control panel

until pitch error has been removed.

to light (approximately 11 minutes) before proceeding

to the next step. When the blue ready lamp comes on,

The output from the roll transmitter is fed to a

this indicates that the gyrocompass rotors have

second control transformer (B16), mounted on the

reached their operating speed of 23,600 rpm and all

compass frame and meshed with the roll gear. The roll

circuits are warmed up and ready to be placed in the

follow-up motor positions the gimbal ring until roll error

RUN mode.

has been removed.

4. When the blue ready lamp comes on, check the

The roll-pitch signals from the control transformers

OWN SHIP COURSE dial (fig. 4-23) to see if the

(B14 and B16) are fed through the first three positions

compass is aligned with the ship's heading. If the

of a stepping relay, to the follow-up amplifiers. The

dial does not indicate the ship's heading, you need to

stepping relay automatically disconnects these

slew the compass until the dial is aligned within a

roll-pitch signals and connects the roll-pitch output

maximum of 10. To slew the compass, turn the

signals from the roll-pitch resolver to the proper

manual azimuth switch either CW (clockwise) or

follow-up amplifier when the main gyros have attained

CCW (counterclockwise) and hold in this position until

sufficient gyroscopic rigidity to take over the

the dial indicates the ship's heading as closely as

stabilization of the roll-pitch phantom.

possible. The nearer the OWN SHIP COURSE dial is

set to the ship's heading, the quicker the compass will

The stepping relay is an 11-deck, 5-position,

settle.

electro-magnet-operated unit located in the system

control assembly (fig. 4-24). This relay, with other time

5. Press the RUN button that is located directly

delay relays, serves to connect the various components

under the blue ready lamp (fig. 4-22), this uncages

automatically at the proper time during the starting

the compass, and the compass will now begin to

sequence. Many operations are involved in starting

settle.

the compass, and the steps must be performed in the

6. Check the IATITUDE COMPUTER dial (fig.

proper sequence and at the proper time to bring the

4-23). If the latitude setting is more than 1 off the local

compass to a usable condition in an optimum amount of

latitude, you must adjust the dial to the correct setting.

time.

A screwdriver adjustment for adjusting the latitude is

located in a hole behind the latitude computer

STARTING SYSTEM.-- The Mk 19 starting

nameplate. To gain access to this adjustment, you need

system is made as nearly automatic as possible. The only

manual operations required of the compass operator are

to remove one of the nameplate screws and rotate the

the master switch, the manual azimuth switch, the fast

nameplate away from the hole.

settle switch, and the run button, located on the compass

7. At the end of 2 hours, the compass should be

control panel (fig. 4-22). The manual azimuth switch

completely settled and transmitting the changes in

operates controls for slewing the compass in azimuth

the ship's actual position with respect to the earth's

that are very similar to those described in the Mk 23

surface. Now, turn the mode selector switch (fig.

system.

4-22) to the NORMAL mode. All alarm lamps should

be lighted green, indicating that the compass is

To start the compass at latitudes below 75, you

operating correctly. If any of the alarm lamps are lighted

should perform the following steps:

red at this time, notify the ship's gyrocompass

technician.

1. Turn the mode selector switch (fig. 4-22) to the

FASTSETTLE mode.

FAST-SETTLING SYSTEM.-- The fast-settling

2. Turn the master switch (fig. 4-22) to the FIL' S

system's function is to reduce the compass period and

increase the percent of damping during starting. This

position, and wait about 30 seconds to allow the tube

filaments to heat.

system reduces the time required for the gyros to assume

4-35