panasonic tx-p50s10b

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • paulstef
    Badcaps Veteran
    • Dec 2013
    • 724
    • Canada

    #41
    Re: panasonic tx-p50s10b

    Measure again the voltage on the reference pin and STB_IN.

    Comment

    • tom66
      EVs Rule
      • Apr 2011
      • 32560
      • UK

      #42
      Re: panasonic tx-p50s10b

      It is important not to connect the main board if you are fiddling with the reference until you are sure the PSU is working, this is to avoid a high standby voltage damaging the main. I have seen 12V come out of a 5V converter with failed feedback, this will obviously not do much for a board where most components will have an absolute maximum operating voltage of 5.5~6V.
      Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
      For service manual, schematic, boardview (board view), datasheet, cad - use our search.

      Comment

      • paulstef
        Badcaps Veteran
        • Dec 2013
        • 724
        • Canada

        #43
        Re: panasonic tx-p50s10b

        Originally posted by tom66
        It is important not to connect the main board if you are fiddling with the reference until you are sure the PSU is working, this is to avoid a high standby voltage damaging the main. I have seen 12V come out of a 5V converter with failed feedback, this will obviously not do much for a board where most components will have an absolute maximum operating voltage of 5.5~6V.
        I didn't even think about this but yes you're so right. There is also the uC on the PSU directly connected to STB_IN 5V... Better be careful.

        Comment

        • ronhayes
          TV Engineer
          • Mar 2014
          • 458
          • UK

          #44
          Re: panasonic tx-p50s10b

          Have checked the ref pin it is now 2.30v

          Comment

          • tom66
            EVs Rule
            • Apr 2011
            • 32560
            • UK

            #45
            Re: panasonic tx-p50s10b

            What is output voltage?
            Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
            For service manual, schematic, boardview (board view), datasheet, cad - use our search.

            Comment

            • ronhayes
              TV Engineer
              • Mar 2014
              • 458
              • UK

              #46
              Re: panasonic tx-p50s10b

              3.80v

              Comment

              • tom66
                EVs Rule
                • Apr 2011
                • 32560
                • UK

                #47
                Re: panasonic tx-p50s10b

                Ok, that is not good then, I think you might have to order a replacement TL431, preferably an exact replacement.
                Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
                For service manual, schematic, boardview (board view), datasheet, cad - use our search.

                Comment

                • paulstef
                  Badcaps Veteran
                  • Dec 2013
                  • 724
                  • Canada

                  #48
                  Re: panasonic tx-p50s10b

                  The relationship almost hasn't changed... 4.73/2.8, or 3.8/2.3... Weird.

                  From here I think you would really need a scope, checking signal on cathode of the TL431 (should be non conducting at 2.3V), the optocoupler input and output, duty cycle of the controller IC...

                  There is only so much you can do with a multimeter.

                  What's the DC voltage on the cathode of the TL431 measured with your meter?

                  Comment

                  • ronhayes
                    TV Engineer
                    • Mar 2014
                    • 458
                    • UK

                    #49
                    Re: panasonic tx-p50s10b

                    Maybe i am reading this all wrong !!
                    I have just measured volts on the IC551 (TL431C ) and what i am getting is pin 1 ref =2.30v pin 2 anode =0v pin3 cathode = 3.80v
                    Have not yet located my scope think i may have stored in the loft.

                    Comment

                    • paulstef
                      Badcaps Veteran
                      • Dec 2013
                      • 724
                      • Canada

                      #50
                      Re: panasonic tx-p50s10b

                      Ok, but what voltage is STB_IN, the power supply for the uC?
                      Attached Files
                      Last edited by paulstef; 04-22-2015, 12:18 PM.

                      Comment

                      • ronhayes
                        TV Engineer
                        • Mar 2014
                        • 458
                        • UK

                        #51
                        Re: panasonic tx-p50s10b

                        Don't know if this will give you any clues but now i have installed this TL431C i get at pin 5 of P7 steady 4.80v with power button pressed in then slowly decreasing volts from 4.80v when power button released. pin 9 of p7 i get 4.58v then 0v when power button pressed. and pin 9 of p25 getting 4.80v steady with power button pressed then slowly decreasing volts from 4.80v when power button released.
                        This is with the plugs disconnected from the A board ?

                        Comment

                        • paulstef
                          Badcaps Veteran
                          • Dec 2013
                          • 724
                          • Canada

                          #52
                          Re: panasonic tx-p50s10b

                          Pin5 of P7 and pin9 of P25 are the same signal, the switched STB voltage (5V). No need to measure both.

                          Anyway... Now we gained 70mV , up from 4.73V to 4.8V. No progress so far.

                          When the mainboard is connected, does the voltage at pin 5 of P7 remain ON even after releasing the push button?

                          Comment

                          • paulstef
                            Badcaps Veteran
                            • Dec 2013
                            • 724
                            • Canada

                            #53
                            Re: panasonic tx-p50s10b

                            I think I would try to force the PSU on by activating the signals PANEL_Main_ON and F_STBY_ON.

                            You would need to connect the 4.8V to these signal inputs on P7 and P25. Without the A-board of course.

                            Comment

                            • ronhayes
                              TV Engineer
                              • Mar 2014
                              • 458
                              • UK

                              #54
                              Re: panasonic tx-p50s10b

                              I get 4.80v at that point.

                              Comment

                              • tom66
                                EVs Rule
                                • Apr 2011
                                • 32560
                                • UK

                                #55
                                Re: panasonic tx-p50s10b

                                @ron, are we sure your multimeter is good?
                                Could you check against a known good reference? Or use another meter?
                                Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
                                For service manual, schematic, boardview (board view), datasheet, cad - use our search.

                                Comment

                                • ronhayes
                                  TV Engineer
                                  • Mar 2014
                                  • 458
                                  • UK

                                  #56
                                  Re: panasonic tx-p50s10b

                                  On pin 5 of p7 i get a steady 4.80v when power button pressed then when power button depressed it drops to less than 1v and slowly decreases from that 1v.
                                  So would i link from pin 5 to pin 6 on p7 and from pin 5 of p7 to pin 11 on p25 or from pin 9 of p25 to pin 11.

                                  Comment

                                  • ronhayes
                                    TV Engineer
                                    • Mar 2014
                                    • 458
                                    • UK

                                    #57
                                    Re: panasonic tx-p50s10b

                                    Tom
                                    I have a couple more cheaper type meters than my M92A one of them is a Hilix DT-830B
                                    I have just put a new battery in it and tried that one and was getting 5,21v at pin 5 p7
                                    (st-by 5v)
                                    I just never thought to try another meter maybe it would be time to invest in a new multi meter,

                                    Comment

                                    • tom66
                                      EVs Rule
                                      • Apr 2011
                                      • 32560
                                      • UK

                                      #58
                                      Re: panasonic tx-p50s10b

                                      Certainly, given that it appears to have put is on the proverbial "wild goose chase", as it appears nothing was wrong with the power supply! But, you live and you learn
                                      Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
                                      For service manual, schematic, boardview (board view), datasheet, cad - use our search.

                                      Comment

                                      • paulstef
                                        Badcaps Veteran
                                        • Dec 2013
                                        • 724
                                        • Canada

                                        #59
                                        Re: panasonic tx-p50s10b

                                        Originally posted by ronhayes
                                        On pin 5 of p7 i get a steady 4.80v when power button pressed then when power button depressed it drops to less than 1v and slowly decreases from that 1v.
                                        So would i link from pin 5 to pin 6 on p7 and from pin 5 of p7 to pin 11 on p25 or from pin 9 of p25 to pin 11.
                                        Yes, and there is probably a sequence to turn them on.
                                        Both signals go to the uC IC701 which will then activate RLY_MAIN and RLY_RUSH.

                                        I'm assuming /RLY_MAIN turns on first and then /RLY_RUSH, therefore first will close relays K604 and K605 and then K602.

                                        Is RF601 the white big resistor near the relays?
                                        Last edited by paulstef; 04-22-2015, 02:29 PM.

                                        Comment

                                        • paulstef
                                          Badcaps Veteran
                                          • Dec 2013
                                          • 724
                                          • Canada

                                          #60
                                          Re: panasonic tx-p50s10b

                                          You turn on one signal and observe what happens and then the other.And post the result here. Like which relay turned on when and which voltages you get on the different connectors.

                                          Be careful :-)

                                          Comment

                                          Related Topics

                                          Collapse

                                          • Andre Gilbert
                                            Panasonic TC-P55ST50 8 blinks then no blinks
                                            by Andre Gilbert
                                            Hello! yes I know there is already lots of information about this issue. I have a Panasonic TC-P55ST50 that originally displayed an 8-blink error code. Following the troubleshooting flowchart, I ended up replacing the SS board. However, even after replacing it, the issue persists. The TV turns on and stays on without displaying an image, and continuity is confirmed on all connectors. What am I missing hereπŸ€”?
                                            Ok Im a mechanical engineer ...but I thought I was able to follow a rather simple flowchart for electric troubleshooting πŸ˜‚.

                                            TV Model: Panasonic TC-P55ST50
                                            ...
                                            11-20-2024, 08:52 PM
                                          • AquaMan Ua
                                            Problem with PANASONIC CF53 laptop after changing BIOS settings
                                            by AquaMan Ua
                                            Hello. I am asking you for a hint on how to solve the problem with my touchbook Panasonic CF53-2 standart model. After setting up the BIOS, the laptop displays the wrong image until Windows loads. (More precisely, it displays, but distorted, instead of the Panasonic image immediately after turning it on, it displays what is in photo #1 in the attached file) Then the image appears when Windows starts loading and then there are no problems with the screen until the reboot. If you enter the BIOS, just a black screen. If you connect an external screen, the image on it is the same as on the built-in...
                                            05-17-2025, 09:40 AM
                                          • stecos
                                            Panasonic Plasma main board repair (ST30 GT30 VT30 ST50 GT50 VT50),LED with 3 blincks
                                            by stecos
                                            Hi everyone!
                                            I happened several times, in the search for help from the web, to consult this very interesting forum.
                                            So I decided to sign up and I intend to participate actively by making available my knowledge and experience on the subject, I'm a new user but at the same time I'm old in the sense that I have 4 decades of experience in repairing and designing electronics but above all I'm a great passionate about the subject.

                                            Having said that I come to the gist of my post on the forum as the title suggests.
                                            For my passion for technology I'm now collecting several...
                                            11-28-2022, 11:39 AM
                                          • aa10aa10
                                            Panasonic Toughbook CF-33 mk1 BIOS repair
                                            by aa10aa10
                                            Good day,

                                            I have tried to remove BIOS supervisor password from Panasonic Toughbook CF-33 mk1. Model number CF-33AENABTG, unfortunately I don't have any other info.

                                            I read the BIOS using afuwin, edited it and tried to flash new edited BIOS using afuwin. Unsuccessfully. Afuwin showed "Error: Problem erasing flash." starting with 0x00040000 and stoped. Then I tried many other options to flash BIOS from Windows without any luck. Finally i rebooted the device - and no post. Afterwards I have read the corrupted bios chip (MX25L12873F) using EZP2010 programmer....
                                            01-21-2025, 06:13 AM
                                          • Mnawar27
                                            Panasonic CF-H2AU24EF3 bios locked
                                            by Mnawar27
                                            Hello ,my Panasonic CF-H2AU24EF3 I get bios password locked after factory reset, can't enter bios
                                            I need help to remove it,
                                            thankyou all.

                                            Panasonic CF-H2AU24EF3
                                            SN; 2FKCA26876...
                                            11-16-2024, 08:00 AM
                                          • Loading...
                                          • No more items.
                                          Working...