8─67 
Adjustment of NSK Unit to GYRO Compass and Log 
 
 
The NSK Unit of the radar equipment is designed to be compatible with almost all types of gyro compass by 
switch operation (For the step motor type, 24 VDC to 100 VDC, and for the synchro-motor type, the primary 
excitation voltage is 50 VAC to 115 VAC). 
Before power-on operation, the switches S1, S2, S5 and jumper JP1 on the NSK Unit (NCT-4106) shall be set 
to the type of gyro compass in use in accordance with the procedures as described below.    The gyro select 
switch on the NSK Unit is set to the gyration ratio of 360X and to be compatible with the synchro type before 
delivery from factory. 
Check the type of the gyro compass used in own ship and make settings in the procedures below.     
 
(1)  Set the switches of the NSK Unit (NCT-4106) before turning on the radar equipment. 
 
• S1:  Set it to [OFF]. 
 
• S2:  There are two types of gyro compasses: a compass of one type outputs a step signal, and the other 
outputs a synchro signal.    Make sure of the type of gyro compass used with the own ship before 
setting S2. 
 
[SYNC]....................................... Synchro signal 
[STEP] ........................................ Step signal 
 
 
• S5:  Set S5 depending on the type of the gyro compass currently in use, according to the S5 setting 
table. 
 
S5-1:  ................................. Set this switch assembly according to the particular type of gyro. 
 
[OFF] .......................................... Synchro signal 
[ON]............................................ Step signal 
 
S5-2, -3............................... Gyration ratio 
 
 360X 180X 90X 36X 
S5-2 OFF OFF ON ON 
S5-3 OFF ON OFF ON 
 
S5-4 .................................... Gyration direction 
 
[OFF] .......................................... Normal (clockwise) 
[ON]............................................ Reverse (counterclockwise) 
 
S5-5 .................................... Log type-1 
 
[OFF] .......................................... Pulse signal 
[ON]............................................ Synchro signal 
 
S5-6 .................................... Not used