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Everything posted by felto

  1. You know that noise that comes on when turning on the monitor
  2. Ok I get squelching noise when I turn the monitor on but no LED light. I also do not get anything on the screen. Let me know if you can help thanks
  3. That part no. is from the working monitor as for the non-working one the part no. is C5302 I checked the diode test from C-E junction and it get a reading of about .4 volts Is there another test from another junction that I can hookup my meter to?
  4. The Horizontal Output Transistor from my old monitor is part no. DE9704
  5. I have another monitor that has one can I just swap to into this one. The part no. is different and I dont know if these things are interchangeable. Will that work?
  6. New York City The part no. for the HOT is C5302 hope that helps
  7. Whats a good site in trying to find a replacement for the Horizontial Output Transistor? thanks
  8. I forgot to ask you on my last post. What value should I get when checking resistance on collector-emitter junction of the HOT? Do I set the volt and the highest resistance scale? Let me know
  9. Step down converter you say. Is that the same as the flyback transformer? Is there an easy way to check this part without disconnecting it from the board. As for the HOT what readings should I get out of it. by doing the diode test I think getting the .6 volts is sufficient no? What else can I check on the mainboard that would likely be the culprit? Thanks always for your help
  10. Go into your systems settings of your control panel then click where it says usb ports and you will see the current supplied for each. I thing it was between 450 and 500MA
  11. It is a Sony monitor and I dont remeber the model no. I do hear it making a sound when it is turns on. The LED power light does not come on when I power it up. The screen remains blank when I power it on. As for the output transistor I do get a .6 volts across collector and emitter when tested. But I get an open between the Base and the Emitter. What is EHT? Let me know if you need more info Thanks again
  12. My computer monitor just went on the frizzs. So I decided to open it up and investigate. I do not see the obvious burnt component and also checked out the fuse if it was burnt. I put a voltmeter on the output transistor and I get around .6 volts which tells me that it is probably good. Can anyone give me some advise on what can be wrong with my monitor. I get no power coming out of the unit when I fire it up. I would really like to fix this because it is a sony monitor and payed alot for it. Any advise will be greatly appreciated. Thanks
  13. Can you tell me what site I can find this step up transformer? Do I just wire it into the other transformer?
  14. ok upon further inspecting the unit it says that it uses 250V and 1 amp. So where do I go from there? It looks as if the transformer is part of the whole unit and it cant be replaced. Can I add something within the circuit to let it run at 110V. Maybe a power transistor or something.............
  15. instead of doind all that why dont you just run jumper wires to whatever part of the circuit it was hooked up to. In other words where it was broken off just take the wires and solder them into the traces where they were connected or find a junction point and solder it there.
  16. Can you tell me what readings are you looking for on the tranformer? I have the unit disassembled and the tranformer is exposed. Where do I hook up my voltmeter and do you need volts, amps or what? Thanks
  17. Pretty neat labs you guys got there Have you guys actually repaired anything in these labs? All i see are broken parts hanging around
  18. Thanks for the reply It says that its at 1ma current and I think 140 watts of power.
  19. Hi I just would like to inquire about a coffegrinder that was given to me from europe. The plug on it was not the standard 110V supply so I changed the plug on it to suit my outlet. Now it still grinds but the problem is that it runs slower. I think I need to change the transformer or something on it. How exactly do I do this and what type of transformer do I need to install to suit my 110V outlet. Thanks
  20. I checked the power supply already with a voltmeter and it checks out ok. I get 30 Volt output which is what it calls for. Something on the board itself burnt out. I think it may be the voltage regulator on the board. Lets hope that is it. It a 7812CT version made by Motorola. I just bought a new one from Radio Shack and am going to solder the new one in tonight. I think it is bad because it gives me an open circuit alert on my voltmeter, which is capable of checking diodes also. Anyway do you know exactly how to check the regulator with a voltmeter. It has three pins to it. One for the input, middle for ground and the third pin is the output. Thanks for your help
  21. but can I test the leads just like I would test a diode?
  22. Thanks Do you know how to test a voltage regulator? I have a 7812CT 3-pin voltage regulator and I think its bad. Can you tell me what pins are what and how to test it with a voltmeter? Its for a multiprinter gizmo and when I hook up the power it sparks back and I get no juice from it. Thanks again for your help
  23. Has anyone ever heard of this switch? It looks like a 'U' shape and has four terminals to it soldered to the circuitboard. In between the 'U' shape is a grove where something blocks the optics and I guess that it turns it on or off. My question is does anyone know how to measure this with a voltmeter? I know there are diodes inside to measure for .6 volts or something but can someone tell me which terminals to test and what readings should I get. Thanks in advance
  24. That has something to do with your phone line that needs distintive device so that your fax can understand your phone line when it is sending a fax. Look into your phone modem options in control panel and there should be something in there about distintive ring. I think you should check that option so that your fax and phone line can communicate with each other.
  25. Hi all, Can anyone help me in fixing my lexmark printer? I have a multiprinter type (scanner, fax, print) and the problem is in the main circuit board of the printer. When I connect the power cord I can see a spark from the connection but I get no power to the unit. The board does not have any fuses where I can check. The only thing I can find is a diode thats right next to the power connection of the board. It gives me an open diode with my voltmeter. I preceeded to change that diode with a new one, but the same thing happens to the diode. Something weird that I dont understand, when I unsolder the diode from the board it give me a .6V reading which is good, but when I solder it to the board it reads an overload, which is a bad diode. Anyone can explain this mystery to me and any help in diagnosing my printer. The board does not have any transformers to. It is part of the plug itself. For your information I have checked all of the other diodes that are soldered to the board and they all come out ok. Its only the one nest to the connector. thanks for your help.
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