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Help finding resistor for Craftsman 82357 R41

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    Help finding resistor for Craftsman 82357 R41

    Hi!

    I have a Craftsman 82357 that has been good to me. It's old, but we've been through a lot and I'd rather not replace it if I don't have to. It's been acting up lately so I pulled it apart and discovered a burned resistor.

    I am not 100% sure of the colour code. It looks like Red Black Red Red Green.

    It's the third red I am not so certain of. I read it as a 20.2 kohm resistor. I see R42, right next to it has Red Black Black Red Green, and I wonder if somehow the that red ban is showing red because it's burnt and should be a black band.

    What do you guys think? If it really is a 20.2 kohm resistor, I am having trouble locating one. Can anyone help me? It's a 1/2 watt 0.5%'er. Thanks!
    Last edited by Spork Schivago; 03-22-2019, 12:07 PM.
    -- Law of Expanding Memory: Applications Will Also Expand Until RAM Is Full

    #2
    Re: Help finding resistor for Craftsman 82357 R41

    Maybe a Yageo MFP50SBRD52-20K2? I just cannot seem to find much for this resistor. DigiKey and Mouser didn't seem to have any resistors that matched this value, unless I wanted to purchase a large quantity of them (DigiKey has that Yageo, but I'd have to purchase 5,000 of them!). Mouser had 20.1 kohm and 20.3 kohm, but no 20.2 kohm resistors.
    Last edited by Spork Schivago; 03-22-2019, 12:23 PM. Reason: Added Mouser info.
    -- Law of Expanding Memory: Applications Will Also Expand Until RAM Is Full

    Comment


      #3
      Re: Help finding resistor for Craftsman 82357 R41

      Originally posted by Spork Schivago View Post
      It's been acting up lately
      How so? What doesn't work and what is happening?

      so I pulled it apart and discovered a burned resistor.
      A clear focused picture in natural sunlight would help us. In addition, a picture of the entire pcb would help us determine what it's role is.

      PS. Craftsman doesn't make its own meters. They get someone to slap on their colors and part number. Since it's made in Korea, maybe Fine Instruments?
      Last edited by retiredcaps; 03-22-2019, 05:03 PM.
      --- begin sig file ---

      If you are new to this forum, we can help a lot more if you please post clear focused pictures (max resolution 2000x2000 and 2MB) of your boards using the manage attachments button so they are hosted here. Information and picture clarity compositions should look like this post.

      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.

      Please do not post inline and offsite as they slow down the loading of pages.

      --- end sig file ---

      Comment


        #4
        Re: Help finding resistor for Craftsman 82357 R41

        It takes well past 100V to roast a 20k 1/2W resistor.
        pcb pics will help. It's probably not 20k.

        It's a nice DMM, I did not know Sears offered such full featured multimeters.

        Comment


          #5
          Re: Help finding resistor for Craftsman 82357 R41

          Originally posted by retiredcaps View Post
          How so? What doesn't work and what is happening?
          I should have listed what was wrong. Taking measurements, such as resistance or checking continuity, sometimes, the meter will lock up. Measuring capacitance, same thing, sometimes, locks right up. Measuring voltage, same thing, sometimes, locks right up. The other day, using it, when it locked up, it showed two decimal points in the readout!

          Originally posted by retiredcaps View Post
          A clear focused picture in natural sunlight would help us. In addition, a picture of the entire pcb would help us determine what it's role is.

          PS. Craftsman doesn't make its own meters. They get someone to slap on their colors and part number. Since it's made in Korea, maybe Fine Instruments?
          I believe this meter was made for Sears by Wens Precision Company, Limited (source for this information: http://greyghost.mooo.com/82357/ )

          I will post clear pictures of both sides of the PCB, however, one side is mostly components, the other side is mostly traces. That might make it a little harder to trace it. I have tried but get lost pretty quick like because of my memory issues.
          -- Law of Expanding Memory: Applications Will Also Expand Until RAM Is Full

          Comment


            #6
            Re: Help finding resistor for Craftsman 82357 R41

            Originally posted by redwire View Post
            It takes well past 100V to roast a 20k 1/2W resistor.
            pcb pics will help. It's probably not 20k.

            It's a nice DMM, I did not know Sears offered such full featured multimeters.
            It was bought for me by my parents when I was very young. If I remember correctly, it actually came from RadioShack. They had it locked in their display case (well, same model, but the display version). That was a very very long time ago though, back in the 90's I believe.

            I cannot say why the resistor failed or even if it has failed, because I currently have no way to measure it without using my DMM. I do not know if the resistor is causing the issues I described. I also noticed residue on the PCB that I cleaned up, thinking perhaps that could have been causing the intermident issues.

            I can not understand, why, if the resistor is what's causing the problem, and the resistor has in fact failed, why the problem is intermitent. It does happen fairly often now (I haven't used it since I cleaned it). These resistors might have something to do with measuring current, I do not know. I generally do not use my DMM to measure current, so I cannot say without testing, if that part of the DMM is broken or not. I also do not use the frequency part or the temperature part of the DMM>
            -- Law of Expanding Memory: Applications Will Also Expand Until RAM Is Full

            Comment


              #7
              Re: Help finding resistor for Craftsman 82357 R41

              I bet I know what I did!!!! Months ago, I was working on a TV and accidently grounded out the leads while measuring voltage across a very large capacitor on a teli! It actually disfigured my probe a little and took a chunk out of it!

              I bet you anything, that fried that 1/2 watt resistor...I just hadn't used the DMM much, if at all, since then to notice any issues. I had gotten caught up in some other non-electrical problems for a while there and had to finish them. So I think I broke it that day, and just never realized it till now.
              -- Law of Expanding Memory: Applications Will Also Expand Until RAM Is Full

              Comment


                #8
                Re: Help finding resistor for Craftsman 82357 R41

                what chipset does it use??

                Comment


                  #9
                  Re: Help finding resistor for Craftsman 82357 R41

                  Originally posted by stj View Post
                  what chipset does it use??
                  The IC says
                  Code:
                  FS9711_LP2
                  9952
                  http://www.fsc.com.tw
                  It was made by Fortune Semiconductor. The wayback machine has info on the FS9711_LP1, but not the LP2. I also believe it's successor was the FS9711_LP3. I could not find a datasheet on the processor, but the wayback machine says this about the FS9711_LP1
                  Code:
                  ╔════════════╦════════╦═════════════════════════════════════════════════════════╗
                  ║  NAME  ║ Pin No.║            Feature              ║
                  ╠════════════╬════════╬═════════════════════════════════════════════════════════╣
                  ║      ║    ║ 1.  ADC display 3 times per min.            ║
                  ║      ║    ║ 2.  Measurement Mode :                 ║
                  ║      ║    ║  DCV : 400.0mv, 4.000 V, 40.00V, 400.0V, 1000V    ║
                  ║      ║    ║  ACV :  00.0mv, 4.000 V, 40.00V, 400.0V, 1000V    ║
                  ║      ║    ║  DCV : (400.0uA, 4000uA), (40.00mA, 400.0mA), (10.00A) ║
                  ║      ║    ║  ACV : (400.0uA, 4000uA), (40.00mA, 400.0mA), (10.00A) ║
                  ║      ║    ║  Resistance : 400.0W, 4.000KW, 40.00KW, 400.0KW,   ║
                  ║      ║    ║        4.000MW, 40.00MW             ║
                  ║      ║    ║  Diode and short circuit testing.           ║
                  ║      ║    ║  Capacity :  4.000nF, 40.00nF, 400.0nF, 4.000uF,   ║
                  ║ FS9711_LP1 ║  64  ║        40.00uF, 200.0uF (30Sec)         ║
                  ║      ║    ║  Frequency : 9.999Hz, 99.99Hz, 999.9Hz, 9.999KHz,   ║
                  ║      ║    ║        99.99KHz, 999.9KHz, 9.999MHz       ║
                  ║      ║    ║  Duty Cycle: 0.1% ~ 99.9%               ║
                  ║      ║    ║ 3.  2*1.5V or 1*3V battery.              ║
                  ║      ║    ║ 4.  Chip duty subsidence is below 6mW.         ║
                  ║      ║    ║ 5.  1/3 bias, 1/4 duty LCD driver circuit.       ║
                  ║      ║    ║ 6.  2.4V battery changing warning.           ║
                  ║      ║    ║ 7.  Build-in OPAMP for DCV/ACV switch.         ║
                  ║      ║    ║ 8.  Build-in CMOS bandgap reference.          ║
                  ║      ║    ║ 9.  Display Hold/Relative/Auto Power-off.       ║
                  ╚════════════╩════════╩═════════════════════════════════════════════════════════╝
                  (source) https://web.archive.org/web/20010728...ish/chiint.htm

                  I removed a couple columns, such as Application Field and Production Status, so the table I made would fit on the screen.

                  Hope this helps! Gonna get some pictures soon of the PCB.
                  -- Law of Expanding Memory: Applications Will Also Expand Until RAM Is Full

                  Comment


                    #10
                    Re: Help finding resistor for Craftsman 82357 R41

                    Here are pictures that were taken in the sunlight. I hope these help.

                    Thanks!
                    Attached Files
                    -- Law of Expanding Memory: Applications Will Also Expand Until RAM Is Full

                    Comment


                      #11
                      Re: Help finding resistor for Craftsman 82357 R41

                      To me, they look like they connect to the fuse there, the one that's used for measuring current.
                      -- Law of Expanding Memory: Applications Will Also Expand Until RAM Is Full

                      Comment


                        #12
                        Re: Help finding resistor for Craftsman 82357 R41

                        There are typically three current-shunt resistors in DMM's
                        0.01R for 10A range (RS)
                        0.99R or 1R for mA range (R40?)
                        99R for uA range (R41?)

                        I would put the meter in uA/mA, and using another multimeter, measure how many ohms is there across COM and current jacks (with good fuse).

                        It might be the uA shunt that is burnt.
                        Otherwise the resistor connects to the rotary switch and I can't trace that to anything in the pics.

                        Comment


                          #13
                          Re: Help finding resistor for Craftsman 82357 R41

                          Originally posted by redwire View Post
                          There are typically three current-shunt resistors in DMM's
                          0.01R for 10A range (RS)
                          0.99R or 1R for mA range (R40?)
                          99R for uA range (R41?)

                          I would put the meter in uA/mA, and using another multimeter, measure how many ohms is there across COM and current jacks (with good fuse).

                          It might be the uA shunt that is burnt.
                          Otherwise the resistor connects to the rotary switch and I can't trace that to anything in the pics.
                          I will track down my analog multimeter. Eventually, I'd love to purchase a used, but calibrated, benchtop meter. A real good one, and perhaps, now is the time to purchase that, in order to help fix this. Any suggestions on a good benchtop meter? I like Agilent, but any top of the notch bench top multimeter would be fine.
                          -- Law of Expanding Memory: Applications Will Also Expand Until RAM Is Full

                          Comment


                            #14
                            Re: Help finding resistor for Craftsman 82357 R41

                            For a bench multimeter, first I tried a Wavetek BDM-40 (LED) cheap on fleabay until I found out the hard way it has no over-voltage or surge protection. So it's easy to damage.

                            Next I ended up getting a HP34401a and replacing the VFD. It's doing OK for now.

                            I have used the new Agilent 34461a and hated it. It has a noisy cooling fan (in a bench multimeter!? ) and the firmware was quite buggy.

                            Comment


                              #15
                              Re: Help finding resistor for Craftsman 82357 R41

                              Originally posted by Spork Schivago View Post
                              A real good one, and perhaps, now is the time to purchase that, in order to help fix this. Any suggestions on a good benchtop meter?
                              Price range? New or used?
                              --- begin sig file ---

                              If you are new to this forum, we can help a lot more if you please post clear focused pictures (max resolution 2000x2000 and 2MB) of your boards using the manage attachments button so they are hosted here. Information and picture clarity compositions should look like this post.

                              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.

                              Please do not post inline and offsite as they slow down the loading of pages.

                              --- end sig file ---

                              Comment


                                #16
                                Re: Help finding resistor for Craftsman 82357 R41

                                Originally posted by redwire View Post
                                For a bench multimeter, first I tried a Wavetek BDM-40 (LED) cheap on fleabay until I found out the hard way it has no over-voltage or surge protection. So it's easy to damage.

                                Next I ended up getting a HP34401a and replacing the VFD. It's doing OK for now.

                                I have used the new Agilent 34461a and hated it. It has a noisy cooling fan (in a bench multimeter!? ) and the firmware was quite buggy.
                                What's the VFD? I want a nice benchtop multimeter, calibrated, certified. I figure eBay would be the source, and I'd get traceable certification for it. I was looking at some HP and Agilent ones. I had one in mind a few years back, but cannot remember which one it was.
                                -- Law of Expanding Memory: Applications Will Also Expand Until RAM Is Full

                                Comment


                                  #17
                                  Re: Help finding resistor for Craftsman 82357 R41

                                  Originally posted by retiredcaps View Post
                                  Price range? New or used?
                                  For this, I think I'd get more bang for my buck going used. I was hoping I wouldn't have to go over 800$, but being used, I want a traceable calibration. DMM don't do me no good if it isn't calibrated.

                                  If I found a good one for, let's say, 200$, I'd buy it! I just don't really want to go over 800$ right now.
                                  -- Law of Expanding Memory: Applications Will Also Expand Until RAM Is Full

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