Denon D-T1

3. VFD is not lit 4. The disc is not ejected
Check the power supply of the VFD driver
(VFD14V)
MAIN PCB
[FB1]
Voltage is input as normal.
When the "
5
" button is pressed, there is no
discharge sound from the disk that runs the
motor.
Check the operation of the "
5
" button
MAIN PCB (ADC_KEY1)
[XP10 : 9pin]
The voltage changes to around 0V when the "
5
"
button is pressed.
Check the state / soldering for the following
parts.
MAIN PCB
[U5, U6, U10]
Check the surrounding circuits.
Check the power supply of the VFD driver (+5VA)
DISPLAY PCB
[U1 : 14, 38pin]
Voltage is input as normal.
Check the power supply of the VFD driver (-24V)
MAIN PCB
[U25 : 1, 3pin]
Voltage is input as normal.
[R25, R29]
Voltage is input as normal.
Check the operation of the VFD driver
DISPLAY PCB
[U1 : 5, 6, 8, 9pin]
No issues in the data line between the VFD driver
and the MCU.
[15-37pin]
No issues in the control line of the VFD.
Check the operation of the VFD (lament)
DISPLAY PCB
[VFD1 : 1, 2, 31, 32pin]
Filament voltage (pulse) is supplied as normal.
Defect in the VFD
DISPLAY PCB
Check or replace the soldering of [VFD1].
Check the state / soldering for the following
parts.
MAIN PCB
Check the circuits around [Q7].
Replace the mechanical.
（Remove the disc by undoing the mecha
screws.）
Check the state / soldering for the following
parts.
DISPLAY PCB
[SW1, ESD1, XP4]
MAIN PCB
[XP10, FB37, R132]
Check the surrounding circuits.
Check the state / soldering for the following
parts.
DISPLAY PCB
[R30, R31, ZD2, C17, C18]
Check the state / soldering for the following
parts.
MAIN PCB
Check the circuits around [U25].
Check the circuits around [D1, D2, Q8].
Check the following
MAIN PCB-DISPLAY PCB
Check of [U10-U1]Data Line.
DISPLAY PCB
[U1]
Check the circuits around [U1].
(U1 may be defective)
Check the state / soldering for the following
parts.
DISPLAY PCB
Check the circuits around [Q1, Q2, Q3, Q4, Q5,
ZD1].
NO NO
NO
NO
NO
NO
NO
YES
YES
YES
YES
YES
YES
YES
Before Servicing
This Unit
Electrical Mechanical Repair Information Updating
40