Thursday, March 03, 2016

Sony COMPACT DISC DECK RECEIVER - SONY HCD-GTR33 - GTR55 - GTR77 – Test mode - panel test procedure – cold reset – Factory preset – power amplifier schematic diagram - STK416-120-E - STK416-130-E - STK433-320-E – Audio system repair and service

                                               Category: Audio System Repair and Service 

Contents of this article 

  • Panel Test mode 
  • Factory Reset procedure 
  • Power Amplifier Circuit diagram 


SONY HCD-GTR33 - GTR55 - GTR77

TEST MODE
PANEL TEST MODE
This mode is used to check the fluorescent indicator tube, LEDs, keys, [MASTER VOLUME] jog, [OPERATION DIAL] jog, model, destination and software version.
Procedure:
1. Press [STOP] button, [METER MODE] button and [DISC SKIP/ EX-CHANGE] button simultaneously.
2. All LEDs and segments in fluorescent indicator tube are lighted up.
3. When you want to enter to the software version display mode, press [DISC 1] button. The model information appears on the fluorescent indicator tube.
# “GVX 1S” is shown for MHC-GTR33.
# “GVX 3S” is shown for MHC-GTR55.
# “GVX 4S” is shown for MHC-GTR77.
Press [DISC 1] button again to view the destination information.
4. During the destination information display, press [DISC 1] button. Each time [DISC 1] button is pressed, the fluorescent indicator tube shows the version of each category software in the following sequence: SC, MTK (DMB Board firmware version), GC, SYS, CD, CDMA, CDMB, ST, TC TA, TM , MTR (METER) and return back to model information display.
5. When [DISC 3] button is pressed while the version numbers are being displayed except model and destination, the date of the software creation appears. When [DISC 3] button is pressed again, the display returns to the software version display. When [DISC 1] button is pressed while the date of the software creation is being displayed, the date of the software creation is displayed in the same order of software version display.
6. Press [DISC 2] button, the key check mode is activated.
7. In the key check mode, the fluorescent indicator tube displays “K 0 V0”.
Each time a button is pressed, “K” value increases. However, once a button has been pressed, it is no longer taken into account. “V” value increases in the manner of 0,1, 2, 3 ... if [MASTER VOLUME] knob is turned clockwise, or it decreases in the manner of 0, 9, 8,7 ... if [MASTER VOLUME] knob is turned counterclockwise.
8. When [DISC SKIP/EX-CHANGE] button is pressed after all LEDs and segments in fluorescent indicator tube light up, alternate segments in fluorescent indicator tube and LEDs would light up. If you press [DISC SKIP/EX-CHANGE] button again, another half of alternate segments in fluorescent indicator tube and LEDs would light up. Pressing [DISC SKIP/ EX-CHANGE] button again would cause all segments in fluorescent indicator tube and LEDs light up.
9. To release from this mode, press three buttons in the same manner as step 1, or disconnect the power cord.
COMMON TEST MODE
This mode is used to check operations of the Amplifier section.
Procedure:
To enter Common Test Mode
1. Press [STOP] button, [METER MODE] button and [OPEN/
CLOSE] button simultaneously.
2. The CD ring indicators flash on the fluorescent indicator tube.
The function is changed to AUDIO and the volume is changed
to VOLUME MIN.
Check of Amplifier
1. Press [EQ BAND/SURROUND] button repeatedly until a message “GEQ MAX” appears on the fluorescent indicator tube. GEQ increases to its maximum.
2. Press [EQ BAND/SURROUND] button repeatedly until a message “GEQ MIN” appears on the fluorescent indicator tube. GEQ decreases to its minimum.
3. Press [EQ BAND/SURROUND] button repeatedly until a message “GEQ FLAT” appears on the fluorescent indicator tube. GEQ is set to flat.
4. When the [MASTER VOLUME] knob is turned clockwise even slightly, the sound volume increases to its maximum and a message “VOLUME MAX” appears on the fluorescent indicator tube.
5. When the [MASTER VOLUME] knob is turned counterclockwise even slightly, the sound volume decreases to its minimum and a message “VOLUME MIN” appears on the fluorescent indicator tube.
To release from Common Test mode
1. To release from this mode, press [STANDBY] button.
2. The cold reset is enforced at the same time.
COLD RESET
The cold reset clears all data including preset data stored in the EEPROM to initial conditions. Execute this mode when returning the set to the customer.
Procedure:
1. Press [STANDBY] button to turn on the system.
2. Press [STOP] button, [ENTER] button, and [STANDBY] button simultaneously.
3. “COLD RESET” appears on the fluorescent indicator tube.
After that, the fluorescent indicator tube becomes blank for a while, and the system is reset.
VACS ON/OFF
This mode is used to switch ON and OFF the VACS (Variable Attenuation Control System).
Procedure:
1. Press [STANDBY] button to turn on the system.
2. Press [STOP] button, [RETURN], and [DISPLAY] button simultaneously. The message “VACS OFF” or “VACS ON” appears on the fluorescent indicator tube.
TUNER STEP CHANGE
The step interval of AM channels can be toggled between 9 kHz
and 10 kHz.
Procedure:
1. Press [?/1 STANDBY] button to turn on the system.
2. Press [TUNER/BAND] button repeatedly to select the “AM”.
3. Press [?/1 STANDBY] button to turn off the system.
4. Press [ENTER] button and [STANDBY] button simultaneously. The system turns on automatically. The message “AM 9K STEP” or “AM 10K STEP” appears on the fluorescent indicator tube and thus the channel step is changed.
CD SHIP MODE (WITH MEMORY CLEAR)
This mode moves the optical pick-up to the position durable to
vibration and clears all data including preset data stored in the EEPROM to initial conditions during the next AC-In. Use this mode
when returning the set to the customer after repair.
Procedure:
1. Press [STANDBY] button to turn on the system.
2. Select CD function.
3. Press [STOP] button, [OPEN/CLOSE] button and [STANDBY] button simultaneously. The system turns off automatically.
4. After the “STANDBY” blinking display finishes, a message
“MECHA LOCK” is displayed on the fluorescent indicator tube and the CD ship mode is set.
CD SHIP MODE (WITHOUT MEMORY CLEAR)
This mode moves the optical pick-up to the position durable to vibration. Use this mode when returning the set to the customer after repair.
Procedure:
1. Press [ STANDBY] button to turn on the system.
2. Select CD function.
3. Press [DISC SKIP/EX-CHANGE] button and [STANDBY] button simultaneously. The system turns off automatically.
4. After the “STANDBY” blinking display finishes, a message “MECHA LOCK” is displayed on the fluorescent indicator tube and the CD ship mode is set.
CD TRAY LOCK MODE
This mode let you lock the disc tray. When this mode is activated, the disc tray will not open when [OPEN/CLOSE] button or [DISC SKIP/EX-CHANGE] button is pressed. The message “LOCKED” will be displayed on the fluorescent indicator tube. This mode only applied when there is disc(s) on the tray.
Procedure:
1. Press [STANDBY] button to turn on the system.
2. Select CD function.
3. Press [STOP] button and [OPEN/CLOSE] button simultaneously and hold down until “LOCKED” or “UNLOCKED” displayed on the fluorescent indicator tube (around 5 seconds).
FACTORY PRESET
This mode is use to load all the factory use preset frequencies into FM 1-FM 20 and AM 1-AM 10. Originally, frequency of FM 1-FM 20 and AM 1-AM10 are set to the minimum frequency.
Procedure:
1. Press [STANDBY] button to turn on the system.
2. Press [EQ BAND/SURROUND] button, [STOP] button, and [DISC 1] button simultaneously and the message “FACTORY” appears on the fluorescent indicator tube. The function is changed to TUNER automatically.

VACS DISPLAY
This mode is used to check the VACS level.
Procedure:
1. Press [STANDBY] button to turn on the system.
2. Press [ERASE] button, [x] button and [ENTER] button simultaneously.
3. The fluorescent indicator tube displays “V0 AP0”. “V” represents Conventional VACS (Triggered by signal level) “AP” represents AP VACS (Abuse Protection Variable Attenuation Control System)
To release from VACS display mode
To release from this mode, do the step (2) again.
METER SWITCH TOUCH COUNT DISPLAY
This mode is used to display the total count of meter pointer touch initial switch and max switch.
Procedure:
1. Press [STANDBY] button to turn on the system.
2. Press [STOP] button, [ENTER] button and [DISPLAY] button simultaneously.
3. The fluorescent indicator tube displays “IxxxxxMyyyyy”. “I” represents the Initial Switch touch. “xxxxx” represents the total count of Initial Switch touch. (Maximum Value of “xxxxx” = 65535) “M” represents the Max Switch touch. “yyyyy” represents the total count of Max Switch touch. (Maximum Value of “yyyyy” = 65535)
To release from Meter Switch Touch Count Display Mode. To release from this mode, do the step (2) again. The fluorescent indicator tube displays “MODE OUT”.
METER TEST MODE
This mode is used to check the meter device.
Procedure:
1. Press [STANDBY] button to turn on the system.
2. Press [STOP ] button, [ENTER] button and [METER MODE] button simultaneously.
3. Meter Backlight LEDs, Meter Pointer LEDs, Power Illuminator LEDs and fluorescent indicator tube are lighted up.
4. When you want to perform count total step from Initial
Switch to Max Switch operation mode, press [>> / >>I / TUNING + ] button. The meter pointer will move from Initial Switch to Max Switch and finally move back to the middle position. The total step count information appears on the fluorescent indicator tube. “xxx STP yy” is shown. “xxx” represents the total step.
(Value of “xxx” should between 430 steps to 470 steps) “yy” represents the status of total step count.
(If total step between 430 steps to 470 steps, “yy” is OK, Else “yy” is NG)
5. When you want to perform count total step from Max Switch to Initial Switch operation mode, press [<< / I<< / TUNING – ] button. The meter pointer will move from Max Switch to Initial Switch and finally move back to the middle position. The total step count information appears on the fluorescent indicator tube. “xxx STP yy” is shown. “xxx” represents the total step.
(Value of “xxx” should between 430 steps to 470 steps) “yy” represents the status of total step count.
(If total step between 430 steps to 470 steps, “yy” is OK, else “yy” is NG)
To release from Meter Test Mode.
To release from this mode, do the step (2) again.
The fluorescent indicator tube displays “TST MODE OUT”.
CDM AGING MODE
This mode is used to display the total count of all disc playing.
Procedure:
1. Press [STANDBY] button to turn on the system.
2. Select CD function and All DISC play mode
3. Put discs on all trays and close the tray.
4. Press [GROOVE] button, [STOP] button and [RETURN] button simultaneously.
5. The fluorescent indicator tube displays Aging Display “AG xxxx/yyyy”. “xxxx” represents the error counter
(Maximum Value of “xxxx” = 9999) “yyyyy” represents the cycle counter (Maximum Value of “yyyy” = 9999)
6. Press [<</ I<< / TUNING – ] or [ >> / >>I / TUNING + ] to search for Aging History Error Display
The fluorescent indicator tube displays “Mx E1E2E3E4”. x: error history number
E1: Loading sequence JCP high
E2: Loading sequence JCP low
E3: Loading operation JCP
E4: Cam position operation JCP
7. Press [RETURN] to Aging Display
To release from CDM Aging Mode.
To release from this mode, press [STANDBY] button or perform COLD RESET operation.
POWER AMPLIFIER CIRCUIT DIAGRAM
STK416-120-E - STK416-130-E - STK433-320-E
CLICK ON THE IMAGE TO ZOOM IN