Yamaha DME24N, Руководство по обслуживанию

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DME24N/DME64N
· Connect a MIDI cable to MIDI IN/OUT.
· Insert a MY-SLOT check Ver. 2 test jig into the SLOT1
– SLOT4.
· Connect a USB cable with the USB terminal and to a
PC.
· Set PHONES LEVEL to MIN unless the section “2-1-
2. PHONES OUT L/R” is performed.
· Perform the testing item No. 26 in the “01. Product” of
the test program if the section “2-1-2. PHONES OUT
L/R” is performed.
· Perform the testing item No. 27 in the “02. Product
(JITTER)” of the test program if the sections “2-1-3.
Checking of PLL Operating Range of DIGITAL Input
from WORD CLOCK IN, SLOT” and “2-1-4. Jitter
Measurement” are performed.
2-1-1. Testing Items and Determination with Test Program
Perform the testing items No. 01–23 in the “01. Product”
of the test program and check if no failure item exists.
∗
Inspections the DME64N.
1-1. Measuring Instruments
See following conditions for the measuring instruments
to be used.
· 100k
Ω
or Greater Input Impedance.
· Weighting with LPF at 12.7kHz, -6dB/OCT during
noise measuring. (Measuring should be performed
at average values, not root-mean-square values.)
· Weighting with LPF at 80KHz, -18dB/OCT during
the measuring of distortion, signal level, and cross
talk.
· 150
Ω
Output Impedance of Oscillator.
2-1. Inspections by Test Program
Preparation
· Connect a cascade cable to CASCADE IN/CASCADE
OUT.
· Connect a BNC cable to WORD CLOCK IN/OUT.
· Connect a COM terminal connection jig for RS232C/
RS422 loop back test to the REMOTE terminal.
· Connect a special jig for GPI loop back test to the
GPI terminal.
Connection Diagram at Test Program Testing
DME64N INSPECTIONS
CASCASE Cable
(68pin)
USB Cable
BNC Cable
PC
MIDI Cable
DME64N
IN/OUT
MIDI
SLOT1/3
SLOT2/4
IN1-16/OUT1-16
GPI
IN/OUT
CASCADE
USB
IN
OUT
WORD CLOCK
REMOTE
COM Terminal Connection Jig
for RS232C/RS422 Loop Back Test
GPI Inspection
Circuit
MY Slot
Check Jig, Ver.2