TESTS WITH THE REPEATERS
Switch on, and measure the output voltages (S1 to S2) and (S3-S4) using a voltmeter.
The voltage should be enough to give about 0.1 to 0.3 amps per winding when the
heading is not moving. More will probably not harm, but it depends on the rating of the
repeater motor,
If this is not the case it will be necessary to change the EPROM.
At rest the two voltage S1-S2 and S3-S4 can be different, and are sometimes zero. Due
to differences in components two KW948s can produce different results, but as long as
they are approximately the same, and the system works, there is no problem.
TESTING THAT REPEATERS FOLLOW
Move heading input. If the repeaters move the wrong way switch off, reverse one pair of
wires, S1-S2. Switch on and try again.
The repeaters will eventually have to be aligned to true heading but for initial tests this is
not necessary.
Move heading and hold it. Check that all the repeaters have followed successfully. Do
the exercise as fast as possible. The KW948 can not go out of synchronisation, and will
follow up if the heading input moves faster than the output rotates.
A good exercise is to use RECSIM simulator and change heading from 000 to 180
degrees. All repeaters should remain in synchronisation.
The output rotation rate can be high or low (10 or 5 degrees per second by default)
according to the setting of jumper J1.
