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Fluke 179 won't tun on

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    #41
    Re: Fluke 179 won't tun on

    the display is a matrix, but has no drive circuitry, the driver is integrated into the microcontroller usually.
    lcd requires a high frequency ac drive btw, if the mcu is dead or the crystal is dead you wont see anything.

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      #42
      Re: Fluke 179 won't tun on

      looking at page9, it can handle 2 crystals or clocks for some reason, and it has a reset/nmi pin that i would check is not stuck low.

      Comment


        #43
        Re: Fluke 179 won't tun on

        So I have attached the micro controller info that TI has. Right now we are interested in page 6 for the pinout, page 9 for block diagram function and pages16,17,18 for terminal functions. If you look at these you will know where to test the frequency and supply voltage. I love TI they tell you everything.
        Attached Files

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          #44
          Re: Fluke 179 won't tun on

          Later on, when I get home I will start measuring.

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            #45
            Re: Fluke 179 won't tun on

            I have turned to Ohm scale, with the switched installed.
            I'm measuring pin #1&2 of the TI IC, which are the digital + and analog + and they are not getting any voltage. Basically, the TI IC is not getting turned on.
            There is a 5 pin VDO(I assume) at the bottom right of the TI IC which also not getting any voltage.
            The measurement,s should I take from the COM, right?

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              #46
              Re: Fluke 179 won't tun on

              Make sure the switch is actually making contact

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                #47
                Re: Fluke 179 won't tun on

                I have placed the PCB in the case and that way I have turned the switch.
                I'm trying to measure DJ Ricoh's measurements, but I'm having problem seeing those small numbers.
                At pin #14 I have the battery voltage of 8.963V.
                At all the pins I'm measuring above 7V. That is normal?
                CD4069UBE

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                  #48
                  Re: Fluke 179 won't tun on

                  Pin#
                  1 - 13= 7.6V and slowly drops
                  14= 8.8V and slowly drops.
                  This slow drop, happens at the battery as well, measured from the COM.

                  Comment


                    #49
                    Re: Fluke 179 won't tun on

                    I'm noticing some kind of yellowish deposit inside the case, specially at the bottom of the meter around the plugs area.
                    Could be a spill victim?

                    Comment


                      #50
                      Re: Fluke 179 won't tun on

                      Originally posted by tibimakai View Post
                      Pin#
                      1 - 13= 7.6V and slowly drops
                      14= 8.8V and slowly drops.
                      This slow drop, happens at the battery as well, measured from the COM.
                      Are you measuring right across the battery when in circuit?
                      Last edited by keeney123; 08-20-2015, 12:28 AM.

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                        #51
                        Re: Fluke 179 won't tun on

                        is the battery good? i know it's a stupid question.

                        start at the board where the battery lead is soldered - i'v had the battery clips fail on stuff before.
                        i suppose there is a voltage regulator circuit we need to find.

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                          #52
                          Re: Fluke 179 won't tun on

                          Originally posted by tibimakai View Post
                          I have placed the PCB in the case and that way I have turned the switch.
                          I'm trying to measure DJ Ricoh's measurements, but I'm having problem seeing those small numbers.
                          At pin #14 I have the battery voltage of 8.963V.
                          At all the pins I'm measuring above 7V. That is normal?
                          CD4069UBE
                          Ill open it again check.

                          Tell me where to focus.
                          Just cook it! It's already broken.

                          Comment


                            #53
                            Re: Fluke 179 won't tun on

                            Thanks for opening yours, but I don't know where should be look for yet.
                            Maybe somebody else can point me what else to check first.
                            The battery has 8.963V.
                            When I measure and use the the battery's negative terminal, or the COM, it seems like the result is the same.
                            We need to find out, how the battery voltage reaches the TI IC.

                            Comment


                              #54
                              Re: Fluke 179 won't tun on

                              Originally posted by tibimakai View Post
                              Thanks for opening yours, but I don't know where should be look for yet.
                              Maybe somebody else can point me what else to check first.
                              The battery has 8.963V.
                              When I measure and use the the battery's negative terminal, or the COM, it seems like the result is the same.
                              We need to find out, how the battery voltage reaches the TI IC.
                              like i said mine got 5.7v

                              i`ll try to trace it down.

                              the sad part is that this is the only dmm at my home
                              Just cook it! It's already broken.

                              Comment


                                #55
                                Re: Fluke 179 won't tun on

                                That is not possible to trace it, if it's the only one dmm that you have. Thanks though, for you effort.

                                Comment


                                  #56
                                  Re: Fluke 179 won't tun on

                                  you need a cheaper meter for "risky" work.

                                  most people i know have a good meter on the bench - usually fluke or UNI-T and a cheap meter for outside work incase it gets lost or damaged.

                                  the same with the soldering iron, good one on the desk, and a cheap one for "away" work.

                                  Comment


                                    #57
                                    Re: Fluke 179 won't tun on

                                    So we need to go back to the information sheet on the micro controller. The supplied voltage to this chip is measured from Vcc to Vss. You can see this on page 53 of the attachment I provide previously. The range of the low supplied voltage is from 1.8 Volt to 3.6 volts maximum this can be seen on page one. If this measurement is at or above 3.6 volts maximum the chip will be damaged. So if you can try to measure this voltage. If it is too hard to measure on the processor then follow the traces back to a component that would be easier to measure. So there are two possible available supplies voltages. One pair is DVcc1 the positive and DVss1 the negative. The other pair is DVcc2 the positive and DVss2 the negative. You will need to measure across each pair. Also, you want to measure the pin under pz terminal which is the 100 pin chip not the 80 pin chip
                                    Last edited by keeney123; 08-20-2015, 05:09 PM.

                                    Comment


                                      #58
                                      Re: Fluke 179 won't tun on

                                      Originally posted by tibimakai View Post
                                      We need to find out, how the battery voltage reaches the TI IC.
                                      Finally, the right question is being asked.

                                      The MSP430 maximum voltage is 3.6V. The Fluke 179 uses a 9V battery.

                                      So something has to drop the voltage down into the 3V range. If the photos weren't so bad, I would be able to see the 5V LDO that you are talking about.

                                      Thus, if the MSP430 isn't getting around 3V, check the 5V LDO. If there is no output on the 5V LDO, check the input voltage on the LDO. If there is no voltage on the input pin, check the trace from the 9V Battery positive terminal to see if the track/via is broken. If I found one broken track, there might be more.

                                      As I said, there are no schematics, but if you photograph the 179 PCB and use a very bright source like the sun from behind, you might be able to see the traces. For example, here is my photo of the UEI DM393

                                      http://www.eevblog.com/forum/repair/...-all-the-time/

                                      As you can see, the picture is focused and you can see all the writing even on the smd components. You can see all the traces despite it being a multilayer board.
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                                      We respectfully ask that you make some time and effort to read some of the guides available for basic troubleshooting. After you have read through them, then ask clarification questions or report your findings.

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                                        #59
                                        Re: Fluke 179 won't tun on

                                        Originally posted by retiredcaps View Post
                                        Finally, the right question is being asked.

                                        The MSP430 maximum voltage is 3.6V. The Fluke 179 uses a 9V battery.

                                        So something has to drop the voltage down into the 3V range. If the photos weren't so bad, I would be able to see the 5V LDO that you are talking about.

                                        Thus, if the MSP430 isn't getting around 3V, check the 5V LDO. If there is no output on the 5V LDO, check the input voltage on the LDO. If there is no voltage on the input pin, check the trace from the 9V Battery positive terminal to see if the track/via is broken. If I found one broken track, there might be more.

                                        As I said, there are no schematics, but if you photograph the 179 PCB and use a very bright source like the sun from behind, you might be able to see the traces. For example, here is my photo of the UEI DM393

                                        http://www.eevblog.com/forum/repair/...-all-the-time/

                                        As you can see, the picture is focused and you can see all the writing even on the smd components. You can see all the traces despite it being a multilayer board.
                                        I have cleaned the image up some. If you magnify it I think you will be able to see the runs.
                                        Attached Files

                                        Comment


                                          #60
                                          Re: Fluke 179 won't tun on

                                          This is the best I can touch up of the picture for you retiredcaps.

                                          Tibimakai the way to take the picture would be to put a white light under it, somewhere around 5000 kelvin. Make sure the board is completely flat. If the light shines around the edges of the board use black paper from the board to the light to block this out just use scotch tape to secure the black paper. Next if your camera has a macro setting then set it to this. Get with-in 30" of the board aim down making sure the camera is completely parallel with the board. Fill up the entire camera view, however close the camera will let you get. Take pictures with flash off and then flash on. With flash off it is best to take picture outside if you can. Good luck.
                                          Attached Files
                                          Last edited by keeney123; 08-20-2015, 09:12 PM.

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