Behringer B2031 Schematic - Active 2 way reference studio monitor speakers

  As is always the case with a two-way active monitor, each B2031 is equipped with two separate power amplifiers – one for the low frequency driver and one for the tweeter (150 watts and 75 watts respectively).  The low frequency polycarbonate driver is 22cm in diameter and the high frequency duties are handled by a one-inch ferofluid-cooled titanium dome tweeter. The crossover circuitry consists of an active fourth-order Linkwitz-Riley filter kicking in at 2kHz. The enclosure also employs a bass reflex porting system to extend the low frequency drivers’ overall frequency response down to a quoted 50Hz.  Other features of the B2031s worthy of note include: protection circuitry to look after the drivers and amplifiers in the event of overload; and electromagnetic shielding to allow close placement of the B2031’s to TV screens and computer monitors without interference.

At the back of the B2031s you’ll find a metal amplifier housing which extends about an inch or so beyond the dimensions of the speaker enclosure itself (H:W:D 400 x 250 x 290mm). The balanced XLR, balanced/unbalanced TRS and 240 volt IEC power cord all connect vertically upwards into the amplifier housing, leaving the back of the B2031s free of plugs jutting out at right angles. This arrangement makes it much easier to place these monitors close to rear walls – not the best placement, admittedly, but sometimes necessary.  The rear panel of the B2031 is also where you’ll find a number of active controls. These include: Input Trim – which adjusts the B2031’s input sensitivity to the signal source; Low Frequency cut – for adapting the B2031s to an additional subwoofer system; Room Compensation – which rolls off bottom-end relative to wall/corner placement (0, - 2, -4, -6dB); and High Frequency – which compensates for the amount of high frequency damping in the monitor environment (0, +2, -2, -4dB). High and low driver mute switches are also included, which the manual suggests are for maintenance and servicing only – although  found them quite useful while setting up, as they allowed  to get a feel for the individual speaker components.  First impressions of the B2031’s were clearly centered on their extended bottom-end and the impressive definition and detail in their stereo imaging. After much listening, and a bit of tweaking of the rear-panel settings, the B2031s did a creditable job of matching themselves to my particular monitoring environment – particularly in their ability to modify the bottom end in order to compensate for their less-than-ideal close-proximity to walls and corners.

Schematic (Circuit diagram)

A first mix on the B2031s – played back on a number of passive monitors I usually use – revealed a few home truths about the differences in working with passive and active monitor designs. Although the essential balance of the mix held up impressively when played back on the passives, overall it sounded a bit lifeless. All that wonderful detail and definition that oozes out of the B2031s gets lost among the inherent limitations of your typical near field passive monitors. In essence, you still need to ‘work the mix’ on the B2031s – sweetening it up, adding punch and color as the music requires – so as to get the mix to translate effectively into the all-pervasive passive world.  From the first time I heard active reference monitors I was a convert – particularly since I had the advantage of comparing a set of active monitors right alongside a passive version from the same manufacturer. The passive pair contained identical speaker components to the active monitors and were being powered by an amplifier of quite reputable design. The difference was such that it didn’t take an audiophile to pick which monitors had more detail and definition.

The Behringer TRUTH B2031s follow in this grand tradition of the active monitor. They certainly grabbed my attention from first listen and continued to impress after countless listening sessions and mixes. At their current price-point the B2031s will certainly keep the competition honest – as well as leaving many similarly priced passive speaker/external amplifier combinations sounding somewhat lifeless.

How to enter service mode – software update – initialization – White balance adjustment - Philips 49 inch LED LCD TVs.

Philips 49PFL4909/F7 – Serial No.: DS1, DS2
Philips 49PFL4609/F7 – Serial No.: DS1, DS2
Philips 49PFL4909/F8 – Serial No.: XA1, XA2, XA3
Philips 49PFL4909/F8 - Serial No.: XA1

Electrical adjustments are required after replacing circuit components and certain mechanical parts. It is important to perform these adjustments only after all repairs and replacements have been completed.  Also, do not attempt these adjustments unless the proper equipment is available.

Test Equipment Required
1. Remote control unit
2. Color Analyzer,
CA-310 (KONICA MINOLTA Luminance meter) or measuring instrument as good as CA-310.

How to set up the service mode

1. Turn the power on.

2. Press [MENU] button to display Setup menu.

3. Select “Features”.

4. Select “Software Upgrade”.

5. Select “Current Software Info”.

6. Press [0], [6], [2], [5], [9], [6] and [INFO] buttons on the remote control unit in this order. The following screen appears.

Purity Check Mode
This mode cycles through full-screen displays of red, green, blue, and white to check for non-active pixels.
1. Enter the service mode.
2. Each time the [7] button on the remote control unit is pressed, the display changes as follows.

3. To cancel or to exit from the Purity Check Mode, press [CH RETURN] or [PREV CH] button.

White Balance Adjustment

The White Balance Adjustment should be performed when replacing the LCD Panel or Digital Main CBA.

Purpose: To mix red and blue beams correctly for pure white.
Symptom of Maladjustment: White becomes bluish or reddish.

Operate the unit for more than 60 minutes.

2. Enter the service mode.

3. Press [VOLUME DOWN] button three times on the remote control unit to select “Drive setting” mode. “Drive” appears in the screen.

4. Set the color analyzer at the CHROMA mode and zero point calibration. Bring the optical receptor pointing at the center of the LCD-Panel. [To avoid interference from ambient light, this adjustment should be done in a dark room]

Note: The optical receptor must be set perpendicularly to the LCD Panel surface.

5. Press [3] button to select the “HDB” for High Drive Blue adjustment. (“HDB” appears in the screen.)

6. Press [MENU] button. The internal Raster signal appears in the screen. (“Internal (Single)” appears in the upper right of the screen as shown below.)

7. Press [CHANNEL UP/DOWN] buttons to adjust the color temperature becomes 12000°K (x= 0.272 / y= 0.278 ± 0.003).

8. Press [2] button to select the “HDG” for High Drive Green adjustment (“HDg” appears in the screen.) and press [CHANNEL UP/DOWN] buttons to adjust the color temperature.

9. Press [1] button to select the “HDR” for High Drive Red adjustment (“HDR” appears in the screen.) and press [CHANNEL UP/DOWN] buttons to adjust the color temperature.

10. If necessary, adjust the “HDB”, “HDG” or “HDR” again.

11. Press [6] button to select the “LDB” for Low Drive Blue adjustment (“LDB” appears in the screen.) and press [CHANNEL UP/DOWN] buttons to adjust the color temperature.

12. Press [5] button to select the “LDG” for Low Drive Green adjustment (“LDG” appears in the screen.) and press [CHANNEL UP/DOWN] buttons to adjust the color temperature.

13. Press [4] button to select the “LDR” for Low Drive Red adjustment (“LDR” appears in the screen.) and press [CHANNEL UP/DOWN] buttons to adjust the color temperature.

14. If necessary, adjust the “LDB”, “LDG” or “LDR” again.

15. Press [VOLUME DOWN] button to shift to the “Debugging Message” mode.  If there is no message under “[WB]” section, this adjustment completes.  If “Drive settings are NG. Retry again.” Is displayed, repeat above steps from 5. to 14. Then check “Debugging Message” again. 

If “Drive settings are NG. Retry again.” is displayed; replace the LCD Panel or Digital Main CBA.
16. To cancel or to exit from the White Balance Adjustment, press [CH RETURN] or [PREV CH] button.

HOW TO INITIALIZE THE LCD TV

The purpose of initialization is to place the set in a new out of box condition. The customer will be prompted to select a language and program channels after the set has been initialized.
To put the program back at the factory-default, initialize the LCD TV using the following procedure.

NOTE: Disconnect any device from the USB Port before you conduct on this procedure.

TYPE A
1. Turn the power on.
2. Enter the service mode.
- To cancel the service mode, press the “Power”  button on the remote control unit.
3. Press [BACK] button to enter the Control Panel Key Confirmation Menu.
4. Press all buttons on the control panel.
5. Press [INFO] button to proceed with the self check mode.
6. Make sure to confirm the "INITIALIZED : OK" appears in the green screen.
7. Unplug the AC Cord and plug it back on again.

TYPE B

1. Turn the power on.

2. Enter the service mode.

- To cancel the service mode, press the “Power”  button on the remote control unit.

3. Press [BACK] button to enter the Control Panel Key Confirmation Menu.

4. Press any button on the control panel.

5. Press [INFO] button to proceed with the self check mode.

6. Make sure to confirm the "INITIALIZED FINISH" appears in the green screen.

7. Unplug the AC Cord and plug it back on again.

FIRMWARE RENEWAL MODE

TYPE A

Equipment Required

a. USB storage device

b. Remote Control Unit

Firmware Update Procedure

1. Turn the power off and unplug the AC Cord.

2. Insert the USB storage device to the USB port.

3. Plug the AC Cord and turn the power on.

4. After few seconds, the menu mode will appear in the screen.

Note: After 30 seconds without an operation, the menu mode will disappear automatically.  To display the menu mode again, press the [MENU] button on the remote control unit.

5. Select “Setup” and press the [OK] button to display the setup menu.

6. Select “Software”.

7. Select “Software update”.

8. Select “USB”.

9. Press the [OK] button on the remote control unit to enter the update mode.

Update file selection screen appears. (Files included in the USB storage device are displayed.)

Note: To cancel the update mode, select “Cancel” and press the [OK] button.
10. Select the file and press [OK] button.
11. The update will start.

Note: If the above screen isn’t displayed, repeat from step 1.
12. Select “Yes” and press the [OK] button to update.
Note: Do not remove the USB storage device or turn the TV off while update is in progress.
13. When the firmware update is completed, and status will be displayed on the screen.

Remove the USB storage device from the USB port.
Turn the power off and turn the power on again.

TYPE B

Equipment Required

a. USB storage device

b. Remote Control Unit

Firmware Update Procedure

User Upgrade (Filename example: TVNB2001_00_PH_XX91_FB1.bin)

Upgrade the firmware only. The setting values will not be initialized.

The User Upgrade and the Firmware Upgrade (Factory Upgrade) will be done by the same file. If you want to upgrade the firmware and initialize the setting values also, add “FACT_” at the beginning of the filename.  If you want to upgrade the firmware only and leave the setting values as they are, eliminate the “FACT_” from the filename.

 Update procedure
1. Turn the power on.
2. Press [MENU] button to display Menu.
3. Select “Features”.
4. Select “Software Upgrade”.
5. Select “Upgrade” to display Upgrade screen.
6. Press [OK] button to display Software Upgrade screen.
7. Select “USB” and press [OK] button.
8. Insert the USB storage device to the USB port.

9. Select “Check” and press [OK] button.
10. Select “Upgrade” and press [OK] button to start software upgrade.

11. The update will start and the status will be displayed.

Note: If the above screen isn’t displayed, repeat from step 1.
The appearance shown in *1 is described as follows.

12. When the firmware update is completed, the status will appear in the screen.

Remove the USB storage device from the USB port.
Turn the power off and turn the power on again.

Factory Upgrade (Firmware Upgrade/Flash Upgrade)

Firmware Upgrade (Filename example: FACT_TVNB2001_00_PH_XX91_FB1.bin)

Upgrade the firmware and initialize the setting values.

The User Upgrade and the Firmware Upgrade (Factory Upgrade) will be done by the same file. If you want to upgrade the firmware and initialize the setting values also, add “FACT_” at the beginning of the filename.

If you want to upgrade the firmware only and leave the setting values as they are, eliminate the “FACT_” from the filename.

Flash Upgrade (Filename example: ALL_TVNB2001_00_PH_XX91_FB1.bin)

Upgrade the firmware and initialize the setting values along with the factory default such as White Balance, etc.

Before the upgrade, you will need to make a note of all the factory default so you will be able to set it back on the TV after the initialization.

The Flash Upgrade will be done by its unique file.

The User Upgrade/Firmware Upgrade (Factory Upgrade) file cannot be used for this upgrade.

Update procedure

1. Turn the power off.

2. Insert the USB storage device to the USB port.

3. Turn the power on.

4. The update will start.

Note: If the relevant screen isn’t displayed, repeat from step 1.

5. When the firmware update is completed, the status will appear in the screen.

Remove the USB storage device from the USB port.

Turn the power off and turn the power on again.  Service mode initial screen with a word “INITIALIZED” will appear in the screen. The color of the word “INITIALIZED” will change from red to green when initialization is completed.

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Click on the schematic to magnify

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Circuit Diagram

Aiwa HT DV50 HTS – DVD system – Power Amplifier and SMPS circuit diagram - STR-F6676 – TA2020-020

Used ICs: STR-F6676 – TA2020-020. Optical pickup – SF-HD3AV / HD3AVC

Circuit diagram (Schematic)

PWB

Optical pick-up

Philips QFU2.1E Chassis LCD TV - SMPS circuits - troubleshooting

Power Supply Unit
For 32", 37", and 55" sets, power supply units should be repaired on component level.  All other power supplies are a black box for Service. When any of these power supplies is defective, a new board must be ordered and the defective one must be returned, unless the main fuse of the board is broken. Always replace a defective fuse with one with the correct specifications. This part is available in the regular market.
Replace safety components, indicated by the symbol , only by components identical to the original ones. Any other component substitution (other than original type) may increase risk of fire or electrical shock hazard.

PLDC-P109B (32" sets) and PLDD-P109A (37" sets)

The output voltages to the chassis are:
* V STB (+3.3 V; stand-by mode)
* V SSB (+12.3 V; on-mode)
* V SND (+12.3 V; audio circuit).

Test instructions 32" & 37"

* check fuse (F101)

* standby check VSTB (C306), measure 3.3 V

* PFC voltage check (C644), measure 380 - 400 V; if no PFC applied, measure 311 @ 220 V

* multi-level check V SSB (C203), measure 12.3 V

* multi-level check V SND (C206), measure 12.3V

* reference voltage check (U401), measure 5.96 V (appr.).

PLDK-P107B (55" sets)

The output voltages to the chassis are:

* V STB (+3.3 V; stand-by mode)

* V SSB (+12.3 V; on-mode)

* V SND (+12.3 V; audio circuit).

Test instructions 55"

* check fuse (F101)

* standby check VSTB (C301), measure 3.3 V

* PFC voltage check (C646), measure 380 - 400 V; if no PFC applied, measure 311 @ 220 V

* multi-level check V SSB (C203), measure 12.3 V

* multi-level check V SND (C202), measure 12.3V

* reference voltage check (U401), measure 5.96 V (appr.).

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