Lexicon MC-1, Service Manual

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MC-1 Service Manual
5-8
9. DTS 56K Test
10. Contrast Test
The Functional Suite is written such that when each individual test is completed the next individual test is
automatically executed. This prevents any operator from having to remember to perform each test. The
suite is set up so that every test is performed.
Any of these tests can be run individually by turning the VOLUME knob to the desired test and pressing the
MUTE F.P. button to execute the test. If the test is selected to be individually run, the test runs
continuously. If the test passes, the VFD will attempt to report the test passes upon each successful
completion. If the test fails the VFD will attempt to report the failure and the test will continue looping on
itself to keep the signal lines active for debugging purposes.
Character Test
The combination of the Character Test and the Block Test verifies that all display segments are functioning.
The Character Test places the same character on all VFD segments. The encoder is then used to change
the character. The test has sufficient variation of characters to verify complete functionality of the display.
The FAT Procedure requires that 3 characters, capital A, capital B, and a variation of the @ symbol be
observed on the VFD.
Block Test
The combination of the Character Test and the Block Test verifies that all display segments are functioning.
The Block Test illuminates all pixels on a single segment of the VFD. The VOLUME knob is then used to
move the block to each segment.
Switch Test
Each button on the front panel is pressed and the following will take place:
The VFD will indicate which front panel button has been pressed.
If the button has any LEDs associated with it, the LEDs will illuminate.
The switches are:
ON/OFF
VCR
DVD
V-DISC
TV
AUX
CD
TUNER
TAPE
REC/ZONE 2
EFFECT
▲
EFFECT ▼
2-CHANNEL
MUTE
LED Test
The LED test illuminates each LED by turning the VOLUME knob clockwise or counter clockwise. As the
VOLUME knob is turned each individual LED is illuminated.
AC3 SPI Test
The AC3 SPI Test requires that before powering on the MC-1 an AC3 board be installed. This test sends
81h to the Zoran DSP 38500 on the AC3 board. This instructs the 38500 to return the version encoded in its