Need schematics or maintenance maual

I will need the model number of your set to assist. also some of the newer sets dont have schematics since they are designed for board replacement repairs only so schematics arent released for most of those models.

Most of the problems with the small guitar amps are blown power amp chips. They usually use chips like the TDA2030 which look like a power transistor.
Most other problems involve broken connectors, bad solder joints or cracked circuit boards. The power supply area is so simple one doesn't need a schematic for that part which is usually just three terminal regulators for +/-15 volts. Schematics are often hard to find.
Try this site, although this is a different model, much of the schematic will likely be the same.

http://elektrotanya.com/marshall_valvestate10_10w_8001_8010.pdf/download.html

first check the print head and printer head cable.
you need to check the fuse of main board and biasing transistor.

If ink flow the joint of head and cable. you need to change both first.
Then you check main board fuse and biasing transistor. Or change main board.
Thanks by
Sk. Abdus Sabur

I assume that should be "SC400"... This is an error which can be reset by turning the MAIN power switch off for a few seconds and then on. The code will be cleared, provided the problem does not happen again.

SC400 - Image transfer belt bias error

Detected Conditions:
- Timing -
While the image transfer belt bias is ON
- Condition -
The feedback voltage is 4.8V or higher, or PWM value is 50% or higher for 500ms continuously.

Possible Causes:
• Poor connections
• Defective high voltage supply board (T1/PCC/BR)
• Defective I/O control board
• Defective main control board
• Worn Transfer Belt

Troubleshooting Procedure:
1. Make sure the high voltage cable and trigger lines are properly connected to the high voltage supply board, I/O control board, and main control board.
2. Replace the high voltage supply board (T1/PCC/BR).
3. Replace the I/O control board.
4. Replace the main control board.
[Signal Check]
• Feedback signal: CN209-9, TP264, or CN211-A4 on I/O control board / CN302-A6 or TP106 on main control board.
• PWM: CN209-10 or TP272 on the I/O control board.

Hello, This is your classic convergence Amplifier IC problem. Here is a way to deal with it. These are generic instrustions: 1) Get the schematic/service manual for this TV (You will need it because it contains the part numbers and component values you will need for replacement) 2) On the schematic/service manual locate the convergence amplifiers (STK392-110, 120, 150) and the biasing resistors (Write the resistor values down from the schematic) 3) Unplug the TV and remove the rear cover to expose the electronic circuitry. 4) Using the schematic/service manual find the physical location of the two convergence amplifiers (Usually attached to a big metal silver in color heat sink) (Basically it will look like two big black six sided flat modules with a lot of pins on the bottom (18-22 to be exact)). 5) After finding the heat sink and amplifiers remove the screws or the tension bar holding the amplifiers in place. 6) Using a soldering iron and a de-soldering device (either a de-soldering pump or de-soldering wick) remove the solder from the pins of the amplifiers and biasing resistors that protrude from the solder side of the circuit board. (Take into mind that you may have to remove the board in order to do this, use the instructions in the schematic/service manual to do this, and make sure you mark everything you remove to make sure you have a guide as to how to put it back) 7) After removing the solder from the pins off the amplifiers and the biasing resistors, remove the resistors making a list of the value, part number, and location on the board (all of this should be in the schematic/service manual). Then remove the two convergence amplifier modules taking care so as not to damage the circuit board. NOTE: The heat sink compound (the white goopy stuff) may have hardened and caused the module to stick to the heat sink, you will have to gently pry the module away from the heat sink, I have used a light application of isopropyl alcohol to dissolve the heat sink paste. 8) Once the modules are loose from the heat sink, you can gradually remove them from the circuit board. 9) Clean the heat sink off by using the alcohol and a heavy paper towel (remove all of the heat sink paste, and yes this is messy) At this point you have removed the two convergence amplifier modules and the biasing resistors and cleaned the heat sink. Now you will have to use your schematic/service manual to find the part locations, values and numbers you will need to replace the old parts I suggest replacing the biasing resistors first. 1) Sort out the resistors you will need and as stated in the schematic/service manual and replace them according to the schematic/service manual locations and part numbers. 2) Solder the components (resistors) in place making sure not to short out anything in the process. 3) Apply heat sink paste to the metal side of the modules one at a time and the put the modules into the circuit board lining up the screw holes of the modules with the screw holes in the heat sink, use the removed screws or tension bar to hold the modules down once in place in the circuit board and on the heat sink. 4) Solder the pins of both amplifier modules to the circuit board, taking care not to short out anything. 5) Reinstall the board to the TV, reconnect all cables removed (DOUBLE CHECK EVERYTHING) If all went well the convergence amps should be working, and you will need to realign the convergence of your TV, I suggest using the AUTO Convergence feature of your TV (Use the instructions in the schematic/service manual). All should be good now. Now these instructions are generic in nature but can be use for a number of Models of Projection TVs. In addition to this also make sure your Yoke transformers on your CRTs are functioning as they should, check the voltages applied to them. I hope this helps, Thank you, Shuttle83 http://www.electron-age-technologies-llc.com

Hello,

This is not a bad tube it is a convergence problem. Your convergence amplifiers are malfunctioning, and need to be replaced. If you have a background in electronics, you can remove the back of the TV locate the Convergence ICs (using the schematic or service manual) and the order the parts you will need which are the two convergence ICs and the biasing resistors (you will see these on the schematic). To remove them unsolder the pins, unscrew the screws holding them on the heat sink and remove them carefully, if they stick use a solvent to break down the adhesion of the heat sink paste. Once loose, take them out and then unsolder the biasing resistors and replace them with the ones you ordered along with the ICs.

To install the new ICs put heat sink paste on the back of the ICs and insert the pins into the proper holes in the circuit board. Screw the screws back in securely, and solder the connections back.

After doing this you will need to perform a convergence adjustment, using the cross hair adjustment screen (access this from your TV menu). and the you will need to do an advance adjustment using the crosshatch pattern (also accessed from your TV menu).

Once these are done use you service manual to follow the procedures on locking the adjustments into the TVs memory.

I hope this helps,

Thank you,

Shuttle83,

http://www.electron-age-technologies-llc.com

Hello,

I posted this before, however it fits your situation so here are my suggestions:

This is not a bad tube it is a convergence problem. Your convergence amplifiers are malfunctioning, and need to be replaced. If you have a background in electronics, you can remove the back of the TV locate the Convergence ICs (using the schematic or service manual) and the order the parts you will need which are the two convergence ICs and the biasing resistors (you will see these on the schematic). To remove them unsolder the pins, unscrew the screws holding them on the heat sink and remove them carefully, if they stick use a solvent to break down the adhesion of the heat sink paste. Once loose, take them out and then unsolder the biasing resistors and replace them with the ones you ordered along with the ICs.

To install the new ICs put heat sink paste on the back of the ICs and insert the pins into the proper holes in the circuit board. Screw the screws back in securely, and solder the connections back.

After doing this you will need to perform a convergence adjustment, using the cross hair adjustment screen (access this from your TV menu). and the you will need to do an advance adjustment using the crosshatch pattern (also accessed from your TV menu).

Once these are done use you service manual to follow the procedures on locking the adjustments into the TVs memory.

I hope this helps,

Thank you,

Shuttle83

Hello nursecmp,

You have a convergence amplifier problem. Now you have two choices: 1) fix it yourself or 2) Get it fix by a qualified TV repair person. Granted if you choose the latter, you will spend about $200-$500 depending on the shop. So as you stated you would want to do this yourself. OK, I will not get into the problems with this, rather I'll give you the basic procedure and the you can search fixya for a more in depth solution (I'll show you how to do this after the basic instruction on how to replace the Convergence Amplifiers (I rarely give these instructions) Here goes:

1) Get the schematic/service manual for this TV (You will need it because it contains the part numbers and component values you will need for replacement)

2) On the schematic/service manual locate the convergence amplifiers (STK392-110, 120, 150) and the biasing resistors (Write the resistor values down from the schematic)

3) Unplug the TV and remove the rear cover to expose the electronic circuitry.

4) Using the schematic/service manual find the physical location of the two convergence amplifiers (Usually attached to a big metal silver in color heat sink) (Basically it will look like two big black six sided flat modules with a lot of pins on the bottom (18-22 to be exact)).

5) After finding the heat sink and amplifiers remove the screws or the tension bar holding the amplifiers in place.

6) Using a soldering iron and a de-soldering device (either a de-soldering pump or de-soldering wick) remove the solder from the pins of the amplifiers and biasing resistors that protrude from the solder side of the circuit board. (Take into mind that you may have to remove the board in order to do this, use the instructions in the schematic/service manual to do this, and make sure you mark everything you remove to make sure you have a guide as to how to put it back)

7) After removing the solder from the pins off the amplifiers and the biasing resistors, remove the resistors making a list of the value, part number, and location on the board (all of this should be in the schematic/service manual). Then remove the two convergence amplifier modules taking care so as not to damage the circuit board. NOTE: The heat sink compound (the white goopy stuff) may have hardened and caused the module to stick to the heat sink, you will have to gently pry the module away from the heat sink, I have used a light application of isopropyl alcohol to dissolve the heat sink paste.

8) Once the modules are loose from the heat sink, you can gradually remove them from the circuit board.

9) Clean the heat sink off by using the alcohol and a heavy paper towel (remove all of the heat sink paste, and yes this is messy)

At this point you have removed the two convergence amplifier modules and the biasing resistors and cleaned the heat sink.

Now you will have to use your schematic/service manual to find the part locations, values and numbers you will need to replace the old parts I suggest replacing the biasing resistors first.

1) Sort out the resistors you will need and as stated in the schematic/service manual and replace them according to the schematic/service manual locations and part numbers.

2) Solder the components (resistors) in place making sure not to short out anything in the process.

3) Apply heat sink paste to the metal side of the modules one at a time and the put the modules into the circuit board lining up the screw holes of the modules with the screw holes in the heat sink, use the removed screws or tension bar to hold the modules down once in place in the circuit board and on the heat sink.

4) Solder the pins of both amplifier modules to the circuit board, taking care not to short out anything.

5) Reinstall the board to the TV, reconnect all cables removed (DOUBLE CHECK EVERYTHING)


If all went well the convergence amps should be working, and you will need to realign the convergence of your TV, I suggest using the AUTO Convergence feature of your TV (Use the instructions in the schematic/service manual).

All should be good now.

Now these instructions are generic in nature but can be use for a number of Models of Projection TVs.

Hello renning,

You may not have to buy a new board. It just might be the Convergence Amplifiers that have gone bad. You may just want to replace them first and then see if it corrects your problem before getting the whole board. The convergence amplifiers are easily identified they are tow big black modules attached to a big metal frame called a heat sync, normally it will be located on the right rear section of the TV set looking at it from the back or it would be located in the middle rear of the set looking at it from the rear. In any even look for two big six sided black components with 21-22 pins, now this is the important parts some electronics parts stores sell what are called Convergence Kits (Yes this problem is so common that they have put kits together to repair this issue), they contain the two modules and the biasing resistors needed to properly do the job. You will have to order the kit for your make and model of TV if they do not have a kit, you will have to use a schematic diagram to find the values of the biasing resistors needed. Once you have the modules and the biasing resistors, you will have to de-solder the modules and the associated resistors and replace them with the ones you purchased. You will also need to detach the modules from the heat sink clean the heat sink (with alcohol) and then attach the new modules (with a new application of heat sink paste, which is the white stuff the you removed with the alcohol) with the screws you removed to detach the modules. Once the modules and biasing resistors are installed you will need to turn on the TV and then perform a convergence setup, your TV most likely will have an auto convergence alignment setup feature on the setup menu , use this to do the convergence alignment setup (check your users manual for help in doing this). The cost for this repair will be as follows:

2 STK392-1XX series Convergence Amplifiers $4.00-$15.00 USD Total $8.00 - $30.00 USD

9-10 biasing resistors $5.00-$10.00 USD (multipack) $15.00 USD

Solder $5.00 USD

Soldering Iron $20.00 USD

Silicone Heat sink paste $6.00 USD

de-soldering brade $5.00

The cost of materials will be about $81.00 on the high end.

The cost of a new board will be about $150.00 - $200.00 depending on the vendor.

You can buy replacement boards from a manufacture approved vendor outlet, go to the manufacture's site find support and parts they should have a listing of supported vendors. I would suggest calling the vendor and ordering from the phone asking them to send you an RMA for the part (board) this protect you from having them asses charges without delivery of product.

You will need the schematic diagram to help you install it schematics can be purchased at http://www.servicemanuals.net
for about $19.00 USD.

I hope this helps,

Thank you,

Shuttle83

Hello n0lcl285,

I gave this advice before and I hope it helps you too.

You may not have to buy a new board. It just might be the Convergence Amplifiers that have gone bad. You may just want to replace them first and then see if it corrects your problem before getting the whole board. The convergence amplifiers are easily identified they are tow big black modules attached to a big metal frame called a heat sync, normally it will be located on the right rear section of the TV set looking at it from the back or it would be located in the middle rear of the set looking at it from the rear. In any even look for two big six sided black components with 21-22 pins, now this is the important parts some electronics parts stores sell what are called Convergence Kits (Yes this problem is so common that they have put kits together to repair this issue), they contain the two modules and the biasing resistors needed to properly do the job. You will have to order the kit for your make and model of TV if they do not have a kit, you will have to use a schematic diagram to find the values of the biasing resistors needed. Once you have the modules and the biasing resistors, you will have to de-solder the modules and the associated resistors and replace them with the ones you purchased. You will also need to detach the modules from the heat sink clean the heat sink (with alcohol) and then attach the new modules (with a new application of heat sink paste, which is the white stuff the you removed with the alcohol) with the screws you removed to detach the modules. Once the modules and biasing resistors are installed you will need to turn on the TV and then perform a convergence setup, your TV most likely will have an auto convergence alignment setup feature on the setup menu , use this to do the convergence alignment setup (check your users manual for help in doing this). The cost for this repair will be as follows:

2 STK392-1XX series Convergence Amplifiers $4.00-$15.00 USD Total $8.00 - $30.00 USD

9-10 biasing resistors $5.00-$10.00 USD (multipack) $15.00 USD

Solder $5.00 USD

Soldering Iron $20.00 USD

Silicone Heat sink paste $6.00 USD

de-soldering brade $5.00

The cost of materials will be about $81.00 on the high end.

The cost of a new board will be about $150.00 - $200.00 depending on the vendor.

You can buy replacement boards from a manufacture approved vendor outlet, go to the manufacture's site find support and parts they should have a listing of supported vendors. I would suggest calling the vendor and ordering from the phone asking them to send you an RMA for the part (board) this protect you from having them asses charges without delivery of product.

You will need the schematic diagram to help you install it schematics can be purchased at http://www.servicemanuals.net
for about $19.00 USD.

I hope this helps,

Thank you,

Shuttle83