Klein Marine Systems, Inc. HydroChart 5000, Operation And Maintenance Manual

Page: 73 / 82

Sonar Head Unit
A-7
LED D9, and measurable at TP9. TPGND1 can be used for ground reference. A
second linear regulator generates 1.2 VDC from the 3.3 VDC source. This is
indicated by green LED D11, and can be measured at TP10.
Some useful test points and waveforms are shown in Figure A-5.
A.4.6 Checking the Transmitter Board
By probing on the Transmitter board you can check that the transmitters are
working. Probe each transmitter output connector (J5-1, 2; J6-1, 2) to view the two
transmitter outputs. These are floating differential output pairs, so the signal levels
at pin 1 and 2 may be unequal. But all four pins should show transmitter outputs
similar to that shown in Figure A-6, and you should see a scope trace similar to the
one shown in the figure. You can select different pulse lengths on the System 5000
Control tab of the
Sonar Interface dialog box. Note that pulse lengths of 2 ms and
greater are generated at a lower amplitude than shorter pulse lengths. The altimeter
transmitter can be checked at J7-1.
Figure A-5:
Multiplexer Board Waveforms
TP18 Telemetry TP17
TP28 TVG curve