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HP W22 lights up then goes dark.

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    #21
    Re: HP W22 lights up then goes dark.

    This link may help.
    http://www.elexp.com/t_test.htm

    But the hissing problem needs sorting first,if its coming from the conector it must be a bad conection problem, if you have something that is burnt then you will be able to see it, if it is not conector, search all components on front and back of board for signs of burning or bad heat damage, or it possible it could be damage to wire or conector to lamp inside screen,

    Once you sort that out, go to page 9 of this thread, DAVMAX gives you every thing you need to know, good luck.

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      #22
      Re: HP W22 lights up then goes dark.

      Thanks Bobdee a great help

      Comment


        #23
        Re: HP W22 lights up then goes dark.

        I am looking at replacing the two transistors in this unit but I cannot get a number off them. On one it looks like ?960GH. Any help would be appreciated.
        Attached Files

        Comment


          #24
          Re: HP W22 lights up then goes dark.

          hello again davg
          its probably 9960gh,
          read post 3 of this thread, by logistics, it will give you info on what you want to know, I think, good luck,
          bob

          Comment


            #25
            Re: HP W22 lights up then goes dark.

            Thanks Bobdee I should have read all post and been more informed. I have Goggled that # can't seem to find a data sheet looks like the # I was looking for though. I highlighted the wrong component in the first picture. here is the right ones. will keep searching.
            I pulled these two fets still can't get a good number off them but I took a chance and put back a couple of 5707's that I had on hand. The screen flickers quite a bit than lights up. I have had it sitting for an hour or so with some flickering and the screen is darker than normal. I still get a hissing sound on startup like a loose connection but I cannot find it.
            Attached Files

            Comment


              #26
              Re: HP W22 lights up then goes dark.

              hello again
              if I understand you righ, you have put c5707 in place of those two that you have highlightedi in photo, If thats the case I think you made error, c5707 are transistors, those are mosfets they have markings on board G D S , transistors would have B E C ,
              (please if you can, someone in the know,help out and confirm,) as I am only hobbyist

              Comment


                #27
                Re: HP W22 lights up then goes dark.

                Originally posted by Bobdee
                hello again
                if I understand you righ, you have put c5707 in place of those two that you have highlightedi in photo, If thats the case I think you made error, c5707 are transistors, those are mosfets they have markings on board G D S , transistors would have B E C ,
                (please if you can, someone in the know,help out and confirm,) as I am only hobbyist
                Thats correct Bobdee and I though both were transistors but than I am not a tech person either just a retiree enjoying a new challenge. As I indicated I now have video whereas before a black screen. I have been searching these numbers but no luck. If anyone knows what the # is on these two mosfets and the spec, it would be greatly appreciated.

                Comment


                  #28
                  Re: HP W22 lights up then goes dark.

                  Originally posted by davg
                  Thanks Bobdee I should have read all post and been more informed. I have Goggled that # can't seem to find a data sheet looks like the # I was looking for though. I highlighted the wrong component in the first picture. here is the right ones. will keep searching.
                  I pulled these two fets still can't get a good number off them but I took a chance and put back a couple of 5707's that I had on hand. The screen flickers quite a bit than lights up. I have had it sitting for an hour or so with some flickering and the screen is darker than normal. I still get a hissing sound on startup like a loose connection but I cannot find it.
                  Is there someone who can tell me what the specifications are for these two frets. Q858 & Q859. It looks like 9960gh but I am unable to find data sheet for that number I have looked through cross references but that number do not appear?? As indicated I have two 5707's in there right now and I know they do not meet the specs.

                  Comment


                    #29
                    Re: HP W22 lights up then goes dark.

                    cancel
                    Last edited by Bobdee; 02-19-2009, 07:25 PM.

                    Comment


                      #30
                      Re: HP W22 lights up then goes dark.

                      Hello again Davg
                      I think I got your mosfet, hope its not to late, try this,



                      good luck
                      bob

                      Comment


                        #31
                        Re: HP W22 lights up then goes dark.

                        Originally posted by Bobdee
                        Hello again Davg
                        I think I got your mosfet, hope its not to late, try this,



                        good luck
                        bob
                        Thanks pal I have looked and looked but to no avail. Appreciate it.

                        Comment


                          #32
                          Re: HP W22 lights up then goes dark.

                          I am having the same issue. How did you remove the back panel; where are the clips located so I can pop this thing off with minimal damage?

                          Thanks

                          Comment


                            #33
                            Re: HP W22 lights up then goes dark.

                            @ davg: if you can't find the exact type you can try with other similar MOSFET.

                            I have searched something close to AP9960GH and I found STF60N55F3 on ST.com.
                            I tried also on Fairchild with a filter of Vds, Id and package and there are several type, the FDD8647L seems a good replacement.
                            The most important parameters are Vds, Id and Rdson, if they are close to the original one, you can try to use them.

                            Ciao
                            Gianni
                            "In the confrontation between the stream and the rock, the stream always wins...Not through strength, but through persistence."
                            H. J. Brown

                            Comment


                              #34
                              Re: HP W22 lights up then goes dark.

                              Hello

                              Please forgive me , english is not my native language

                              I have repaired several monitors like the mentioned one

                              Mainly, I you have CHI MEI LCD, your problem is CCFL related,

                              Comment


                                #35
                                Re: HP W22 lights up then goes dark.

                                Originally posted by davg
                                I am looking at replacing the two transistors in this unit but I cannot get a number off them. On one it looks like ?960GH. Any help would be appreciated.
                                POATE TE AJUTA.
                                Attached Files

                                Comment


                                  #36
                                  Re: HP W22 lights up then goes dark.

                                  Where may one find a schematic diagram for this monitor?

                                  Comment


                                    #37
                                    Re: HP W22 lights up then goes dark.

                                    Hello friends! I Too received a HP w22 monitor as a "freebie" in a collection I picked up from a friend who bought new computers, and it is in MINT shape.....except it only stays on for a minute or two, and then goes black. I suspected the inverter circuit and I am inclined to believe that the two FETS mentioned in this thread are bad -- I asked the original owner and he said it went out right after (or during?) a thunderstorm. Of course, He had no surge protector. I have ordered a set of these FETS and will do a replacement of both -- All the caps, other active and passive components come up good in my tests, but the two FETS are a bit shakey -- I think they break down as soon as they start to get warm. If this repairs the monitor, I will post for everyone so they can perform the same operation. Thanks to everyone for their input!!

                                    Comment


                                      #38
                                      Re: HP W22 lights up then goes dark.

                                      Originally posted by TAG333 View Post
                                      Where may one find a schematic diagram for this monitor?
                                      I have tried to get a schematic for this unit for months on end -- Forget asking HP as you can't even buy one. Local shops don't have or can't get it either! The best I can do is reverse engineer it in my spare time. If I get the schematic together, I will post it or offer it FREE by email.

                                      Comment


                                        #39
                                        Re: HP W22 lights up then goes dark.

                                        Originally posted by fjbirdman View Post
                                        Hello friends! I Too received a HP w22 monitor as a "freebie" in a collection I picked up from a friend who bought new computers, and it is in MINT shape.....except it only stays on for a minute or two, and then goes black. I suspected the inverter circuit and I am inclined to believe that the two FETS mentioned in this thread are bad -- I asked the original owner and he said it went out right after (or during?) a thunderstorm. Of course, He had no surge protector. I have ordered a set of these FETS and will do a replacement of both -- All the caps, other active and passive components come up good in my tests, but the two FETS are a bit shakey -- I think they break down as soon as they start to get warm. If this repairs the monitor, I will post for everyone so they can perform the same operation. Thanks to everyone for their input!!
                                        Mind if I ask what your tests are? I'm always up for learning new ways if I don't do them myself already. If I can get a hold of this guy on craigslist, I might be getting a HP w2207 myself, so if you could post your results that would be great!

                                        Comment


                                          #40
                                          Re: HP W22 lights up then goes dark.

                                          Here is an interesting thing from my work with this monitor I determined there were sharp edges that nicked the wires that run to the CCFL's I could see rust spots so I carefully plugged it in and powered it on outside of the case and seen that it was sparking and smoking in these corners appears that chi mei problems are indeed mostly backlight related so check your wires check for oxidation on your monitor you will find oxidation because of the electrical charge the frame is getting at certain points.

                                          Be very careful when testing there is a risk of electric shock! I am not responsible for your injuries! Or damage caused to anything or anyone!
                                          Please note: I am not responsible for any harm caused to you anything discussed is just discussion. Before you try anything discussed be sure that you have the appropriate knowledge and safety gear for the job. Like with anything education and safety are first! Do not try anything @ home without it.

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