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RE: [softrock40] Re: Need to confirm Si570 distroyed

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  • MIKE DURKIN
    you could send it to me and i can test it .... To: softrock40@yahoogroups.com From: billsmith952@yahoo.com Date: Mon, 22 Jul 2013 03:57:07 +0000 Subject:
    Message 1 of 20 , Jul 21 9:14 PM
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      you could send it to me and i can test it ....


      To: softrock40@yahoogroups.com
      From: billsmith952@...
      Date: Mon, 22 Jul 2013 03:57:07 +0000
      Subject: [softrock40] Re: Need to confirm Si570 distroyed

       
      I decided to replace the SMD cap at c51, just in case that was the cause of my problems. The CFGSR results are the same, so just need a way to confirm the Si570 chip bad.

      Thanks,
      Bill

      --- In softrock40@yahoogroups.com, "billsmith952" <billsmith952@...> wrote:
      >
      > I probably have destroyed my Si570 while attempting to remove solder bridge between pad 7 and the metal above and to the right of pad 7 (got it removed with razor blade). Also may have damaged 0.1 uF SMD cap at C51. The CFGSR program always says "No Si570 connected" on the test tab. Also, even after unclicking the ABPF enable, I am unable to change the frequency on the tune tab.
      >
      > My resistance measurements between ground (pad 3) and the other pads is as follows:
      > Pad Measure
      > 4 1.27M ohms
      > 5 infinite
      > 6 15.1M ohms
      > 7 infinite
      > 1 infinite
      > 2 1.8M ohms
      >
      > Any way to confirm status?
      >
      > Thanks,
      > Bill
      >


    • Alan
      ... Subject: [softrock40] Need to confirm Si570 distroyed ... Bill, A good way of removing excess solder and cleaning joints is solder wick, a very bad way is
      Message 2 of 20 , Jul 21 11:33 PM
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        ----- Original Message -----
        Subject: [softrock40] Need to confirm Si570 distroyed


        >I probably have destroyed my Si570 while attempting to remove solder bridge between pad 7 and the metal above and to the right of
        >pad 7 (got it removed with razor blade).

        Bill,

        A good way of removing excess solder and cleaning joints is solder wick, a very bad way is a raz...
        The Si570 is, like most modern components very tough, maybe yours is OK.


        >Also may have damaged 0.1 uF SMD cap at C51. The CFGSR program always says "No Si570 connected" on the test tab. Also, even after
        >unclicking the ABPF enable, I am unable to change the frequency on the tune tab.
        >
        > My resistance measurements between ground (pad 3) and the other pads is as follows:
        > Pad Measure
        > 4 1.27M ohms
        > 5 infinite
        > 6 15.1M ohms
        > 7 infinite
        > 1 infinite
        > 2 1.8M ohms
        >

        In circuit resistance readings are not usually particularly useful apart from checking for shorts to ground especially from the 5v
        and 3V3 power lines. Also other places to ground and adjacent pins. Yours, maybe, could indicate bad solder joints.

        Far better are voltage checks after checking for shorts. Have you got the 5V and 3V3? What are the voltages on the Si570 pins?

        Can you detect 56.34 or possibly 28.2MHz from the Si570?

        Most times Si570 problems are just bad solder joints.

        73 Alan G4ZFQ
      • billsmith952
        Thanks for your response Alan. I had tried your technique: I put some rosin on pad 7 bit of solder, then used the solder wick. I also placed a bit of solder on
        Message 3 of 20 , Jul 22 10:32 AM
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          Thanks for your response Alan.

          I had tried your technique: I put some rosin on pad 7 bit of solder, then used the solder wick. I also placed a bit of solder on the iron to make a good connection with the wick, I could not remove what appeared to be a bridge between pad 7 and the metal outcropping on Si570 (there are 2 each above and to the left and right of pads 4 and 7). I tried it at least 4 times, and might have destroyed the chip in the process. I finally resorted to the razor blade. The bridge appears to be gone.

          The voltages on the Si570 are as follows (3.28 at R10 for your reference; ground is pin 4 of the ATTiny85):
          pad 1 .004 volts
          pad 2 3.28 volts
          pad 3 (ground) 0 volts
          pad 4 3.28 volts
          pad 5 0 volts (sometime it is 1.6, but that is probably the SMD cap next to it)
          pad 6 0 volts
          pad 7 0.432 volts (the site of the "crime")

          I am unable to detect any mHz on Si570. I can only get the "No Si570 connected or" on the test tab of CFGSR program. I am also unable to manipulate the frequency on the tune tab.

          In the troubleshooting section of the LCL Osc section, it says that it should receive "12C signals". I don't believe that this is happening.

          (I have plugged in the board, started the CFGSR prog, turned off the Enable ABPR, and reconnected.)

          I tried a Calibrate function, and get the following error: "Xtal 1.#INFOO not in rage (LO=112 high=117MHz)Writing factory default to device!"

          Let me know if I can do any further tests. I have very limited electronics knowledge, and may have forgotten to do something very basic.

          Very best regards,
          Bill KC0TBO

          --- In softrock40@yahoogroups.com, "Alan" <alan4alan@...> wrote:
          >
          >
          > ----- Original Message -----
          > Subject: [softrock40] Need to confirm Si570 distroyed
          >
          >
          > >I probably have destroyed my Si570 while attempting to remove solder bridge between pad 7 and the metal above and to the right of
          > >pad 7 (got it removed with razor blade).
          >
          > Bill,
          >
          > A good way of removing excess solder and cleaning joints is solder wick, a very bad way is a raz...
          > The Si570 is, like most modern components very tough, maybe yours is OK.
          >
          >
          > >Also may have damaged 0.1 uF SMD cap at C51. The CFGSR program always says "No Si570 connected" on the test tab. Also, even after
          > >unclicking the ABPF enable, I am unable to change the frequency on the tune tab.
          > >
          > > My resistance measurements between ground (pad 3) and the other pads is as follows:
          > > Pad Measure
          > > 4 1.27M ohms
          > > 5 infinite
          > > 6 15.1M ohms
          > > 7 infinite
          > > 1 infinite
          > > 2 1.8M ohms
          > >
          >
          > In circuit resistance readings are not usually particularly useful apart from checking for shorts to ground especially from the 5v
          > and 3V3 power lines. Also other places to ground and adjacent pins. Yours, maybe, could indicate bad solder joints.
          >
          > Far better are voltage checks after checking for shorts. Have you got the 5V and 3V3? What are the voltages on the Si570 pins?
          >
          > Can you detect 56.34 or possibly 28.2MHz from the Si570?
          >
          > Most times Si570 problems are just bad solder joints.
          >
          > 73 Alan G4ZFQ
          >
        • The Silver Fox
          I doubt that soldering iron temperatures can harm the chip. The instructions from SiLabs indicates heating it in an oven to purge it of moisture which is far
          Message 4 of 20 , Jul 22 11:06 AM
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            I doubt that soldering iron temperatures can harm the chip.  The instructions from SiLabs indicates heating it in an oven to purge it of moisture which is far hotter than most irons.

            73,

            Alan – W6ARH

             

             

            From: softrock40@yahoogroups.com [mailto:softrock40@yahoogroups.com] On Behalf Of billsmith952
            Sent: Monday, July 22, 2013 10:33 AM
            To: softrock40@yahoogroups.com
            Subject: [softrock40] Re: Need to confirm Si570 distroyed

             

             

            Thanks for your response Alan.

            I had tried your technique: I put some rosin on pad 7 bit of solder, then used the solder wick. I also placed a bit of solder on the iron to make a good connection with the wick, I could not remove what appeared to be a bridge between pad 7 and the metal outcropping on Si570 (there are 2 each above and to the left and right of pads 4 and 7). I tried it at least 4 times, and might have destroyed the chip in the process. I finally resorted to the razor blade. The bridge appears to be gone.

            The voltages on the Si570 are as follows (3.28 at R10 for your reference; ground is pin 4 of the ATTiny85):
            pad 1 .004 volts
            pad 2 3.28 volts
            pad 3 (ground) 0 volts
            pad 4 3.28 volts
            pad 5 0 volts (sometime it is 1.6, but that is probably the SMD cap next to it)
            pad 6 0 volts
            pad 7 0.432 volts (the site of the "crime")

            I am unable to detect any mHz on Si570. I can only get the "No Si570 connected or" on the test tab of CFGSR program. I am also unable to manipulate the frequency on the tune tab.

            In the troubleshooting section of the LCL Osc section, it says that it should receive "12C signals". I don't believe that this is happening.

            (I have plugged in the board, started the CFGSR prog, turned off the Enable ABPR, and reconnected.)

            I tried a Calibrate function, and get the following error: "Xtal 1.#INFOO not in rage (LO=112 high=117MHz)Writing factory default to device!"

            Let me know if I can do any further tests. I have very limited electronics knowledge, and may have forgotten to do something very basic.

            Very best regards,
            Bill KC0TBO

            --- In softrock40@yahoogroups.com, "Alan" <alan4alan@...> wrote:
            >
            >
            > ----- Original Message -----
            > Subject: [softrock40] Need to confirm Si570 distroyed
            >
            >
            > >I probably have destroyed my Si570 while attempting to remove solder bridge between pad 7 and the metal above and to the right of
            > >pad 7 (got it removed with razor blade).
            >
            > Bill,
            >
            > A good way of removing excess solder and cleaning joints is solder wick, a very bad way is a raz...
            > The Si570 is, like most modern components very tough, maybe yours is OK.
            >
            >
            > >Also may have damaged 0.1 uF SMD cap at C51. The CFGSR program always says "No Si570 connected" on the test tab. Also, even after
            > >unclicking the ABPF enable, I am unable to change the frequency on the tune tab.
            > >
            > > My resistance measurements between ground (pad 3) and the other pads is as follows:
            > > Pad Measure
            > > 4 1.27M ohms
            > > 5 infinite
            > > 6 15.1M ohms
            > > 7 infinite
            > > 1 infinite
            > > 2 1.8M ohms
            > >
            >
            > In circuit resistance readings are not usually particularly useful apart from checking for shorts to ground especially from the 5v
            > and 3V3 power lines. Also other places to ground and adjacent pins. Yours, maybe, could indicate bad solder joints.
            >
            > Far better are voltage checks after checking for shorts. Have you got the 5V and 3V3? What are the voltages on the Si570 pins?
            >
            > Can you detect 56.34 or possibly 28.2MHz from the Si570?
            >
            > Most times Si570 problems are just bad solder joints.
            >
            > 73 Alan G4ZFQ
            >

          • Alan
            ... Subject: [softrock40] Re: Need to confirm Si570 distroyed ... I m not sure. no connection but I think it usually has a voltage. ... Should be, I think
            Message 5 of 20 , Jul 22 12:01 PM
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              ----- Original Message -----
              Subject: [softrock40] Re: Need to confirm Si570 distroyed


              >
              > The voltages on the Si570 are as follows (3.28 at R10 for your reference; ground is pin 4 of the ATTiny85):

              > pad 1 .004 volts

              I'm not sure. no connection but I think it usually has a voltage.

              > pad 2 3.28 volts
              > pad 3 (ground) 0 volts
              > pad 4 3.28 volts

              Should be, I think about 1V6

              > pad 5 0 volts (sometime it is 1.6, but that is probably the SMD cap next to it)

              Again should be about 1V6

              > pad 6 0 volts

              Are you sure? This is the 3V3 feed.

              > pad 7 0.432 volts (the site of the "crime")
              >

              Try this with the ATTiny removed.

              Pin 8??
              Carefully check again.

              > I am unable to detect any mHz on Si570. I can only get the "No Si570 connected or" on the test tab of CFGSR program.

              No point in doing anything else until this error message is not seen.


              73 Alan G4ZFQ






              > I am also unable to manipulate the frequency on the tune tab.
              >
              > In the troubleshooting section of the LCL Osc section, it says that it should receive "12C signals". I don't believe that this is
              > happening.
              >
              > (I have plugged in the board, started the CFGSR prog, turned off the Enable ABPR, and reconnected.)
              >
              > I tried a Calibrate function, and get the following error: "Xtal 1.#INFOO not in rage (LO=112 high=117MHz)Writing factory default
              > to device!"
              >
              > Let me know if I can do any further tests. I have very limited electronics knowledge, and may have
            • billsmith952
              Thanks for the reminder - There were 8 pads, not 7! The readings have been changing. Here are the new ones, followed by ones that I get after a few minutes and
              Message 6 of 20 , Jul 22 3:31 PM
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                Thanks for the reminder - There were 8 pads, not 7!

                The readings have been changing. Here are the new ones, followed by ones that I get after a few minutes and now:
                Pad 1 - 0.02 volts - 0.02 - 0.00
                Pad 2 - 3.28 volts - 3.24 - 0.00
                pad 3 - 0.00 volts - -0.03 - 0.00
                pad 4 - 0.00 volts - -0.03 - 0.00
                pad 5 - 0.00 volts - -0.03 - 0.00
                pad 6 - 3.28 volts - 3.24 - 0.00
                pad 7 - 0.42 volts - 0.40 - 0.00
                pad 8 - 3.28 volts - 3.24 - 0.00 - All this while pad 5 of the 3.3 regulator says 3.28!

                Comments:
                My lack of experience showed on electronics - I had assumed that the numbering started at pad 1, then increased clockwise (pad 3 ground was the 3rd one going clockwise) the rest of the way around.

                When I connected to CFGSR prog, I got a different message. This time on the Test tab, instead of "No Si570 connected or", I now get "?? RX Power down ??".

                When I do a calibrate, I get "Si570 not powered on?"

                I have unable been able to determine why output from my 3.3 regulator varies from 3.28 to 3.24.

                Summary:
                I have been writing this e-mail over a period of about 2 hours. The readings are getting worse (from my perspective). I am trying to get consistent measurements. -I am guessing the the Si570 was "sorta" working, and is now failing. What do you think?

                Again, my thanks to you as you are helping me learn some basics.

                Thank you for your patience.

                Very best regards,

                Bill KC0TBO

                --- In softrock40@yahoogroups.com, "Alan" <alan4alan@...> wrote:
                >
                >
                > ----- Original Message -----
                > Subject: [softrock40] Re: Need to confirm Si570 distroyed
                >
                >
                > >
                > > The voltages on the Si570 are as follows (3.28 at R10 for your reference; ground is pin 4 of the ATTiny85):
                >
                > > pad 1 .004 volts
                >
                > I'm not sure. no connection but I think it usually has a voltage.
                >
                > > pad 2 3.28 volts
                > > pad 3 (ground) 0 volts
                > > pad 4 3.28 volts
                >
                > Should be, I think about 1V6
                >
                > > pad 5 0 volts (sometime it is 1.6, but that is probably the SMD cap next to it)
                >
                > Again should be about 1V6
                >
                > > pad 6 0 volts
                >
                > Are you sure? This is the 3V3 feed.
                >
                > > pad 7 0.432 volts (the site of the "crime")
                > >
                >
                > Try this with the ATTiny removed.
                >
                > Pin 8??
                > Carefully check again.
                >
                > > I am unable to detect any mHz on Si570. I can only get the "No Si570 connected or" on the test tab of CFGSR program.
                >
                > No point in doing anything else until this error message is not seen.
                >
                >
                > 73 Alan G4ZFQ
                >
                >
                >
                >
                >
                >
                > > I am also unable to manipulate the frequency on the tune tab.
                > >
                > > In the troubleshooting section of the LCL Osc section, it says that it should receive "12C signals". I don't believe that this is
                > > happening.
                > >
                > > (I have plugged in the board, started the CFGSR prog, turned off the Enable ABPR, and reconnected.)
                > >
                > > I tried a Calibrate function, and get the following error: "Xtal 1.#INFOO not in rage (LO=112 high=117MHz)Writing factory default
                > > to device!"
                > >
                > > Let me know if I can do any further tests. I have very limited electronics knowledge, and may have
                >
              • Alan
                ... Subject: [softrock40] Re: Need to confirm Si570 distroyed ... Bill, I ve checked, this is normally around 3V3 ... Pads 3,4 should be around 1V5 ... Power
                Message 7 of 20 , Jul 23 1:16 AM
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                  ----- Original Message -----
                  Subject: [softrock40] Re: Need to confirm Si570 distroyed


                  > Thanks for the reminder - There were 8 pads, not 7!
                  >
                  > The readings have been changing. Here are the new ones, followed by ones that I get after a few minutes and now:
                  > Pad 1 - 0.02 volts - 0.02 - 0.00

                  Bill,
                  I've checked, this is normally around 3V3

                  > Pad 2 - 3.28 volts - 3.24 - 0.00
                  > pad 3 - 0.00 volts - -0.03 - 0.00
                  > pad 4 - 0.00 volts - -0.03 - 0.00
                  > pad 5 - 0.00 volts - -0.03 - 0.00

                  Pads 3,4 should be around 1V5

                  > pad 6 - 3.28 volts - 3.24 - 0.00

                  Power to Si570.
                  If you are definite about this there must be a break somewhere between the regulator and Si570. I'd say soldering but just possibly
                  a crack in the PCB track.

                  > pad 7 - 0.42 volts - 0.40 - 0.00

                  As before, should be 3V3. Check with ATTiny removed. Check R10 value and it's soldering. Could also be due to fault at Q1. (Yes, and
                  possibly the Si570)
                  Until this is right you will not control the Si570.

                  > pad 8 - 3.28 volts - 3.24 - 0.00 -

                  >All this while pad 5 of the 3.3 regulator says 3.28!
                  >
                  > Comments:
                  >
                  > When I connected to CFGSR prog, I got a different message. This time on the Test tab, instead of "No Si570 connected or", I now
                  > get "?? RX Power down ??".
                  >
                  > When I do a calibrate, I get "Si570 not powered on?"
                  >

                  Until the voltages are correct do not worry about CFGSR. "RX Power down" means the USB driver is not connected to CFGSR, "Si570 not
                  powered on" means the Si570 is not connected to CFGSR. But forget CFGSR.

                  > I have unable been able to determine why output from my 3.3 regulator varies from 3.28 to 3.24.
                  >

                  This is a very small change. Possibly due to the Si570 not taking current in fault mode.

                  > Summary:
                  > I have been writing this e-mail over a period of about 2 hours. The readings are getting worse (from my perspective). I am trying
                  > to get consistent measurements. -I am guessing the the Si570 was "sorta" working, and is now failing. >
                  >

                  It is impossible to say right now.
                  You have the basic 3V3 power fault which is NOT the Si570.
                  I always suspect soldering, it is not easy and many have declared theirs is good only to find later that resoldering cures a
                  problem.
                  And your comment about solder wick makes me think maybe your bit is not ideal. I suggest you look for the pad 6 fault, get a good
                  bit that will get close to the Si570 and clean as much solder as possible from it.

                  73 Alan G4ZFQ
                • billsmith952
                  You ve given me a number of things to try. One potential disaster: I read your idea of a possible crack in the PCB. This led me to try and reheat my SMD
                  Message 8 of 20 , Jul 23 1:57 PM
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                    You've given me a number of things to try.

                    One potential disaster: I read your idea of a possible crack in the PCB. This led me to try and reheat my SMD contacts to repair any cold solder joints. I was shocked to hear the "DONG ding" of a USB device removal while reheating some of the pads around the 3.3 volt regulator - I had left the USB plugged into the board! I thought that I had one permanent damage to my ATTiny85 microchip. I took it out for a few hours. I reinstalled, and was pleasantly surprised to hear the "ding DONG". Hopefully, no permanent damage done.

                    After reheating a number of joints and adding solder to a few (Some pads had gotten insufficient solder, as I soldered the paid only to avoid bridges), I have been taking measurements:

                    pad 1 spec 3.3 me 3.23
                    Pad 2 spec 3.3 me 3.23
                    pad 3 spec 0.0 me -.038 Note: ground
                    pad 4 spec 1.5 me 1.52, but sometimes to 3.23 (connection to pad 8?)
                    pad 5 spec 1.6 me 0.00
                    pad 6 spec 3.3 me 3.24 Note: after reheating a few pads, this reading is now stable here
                    pad 7 spec 3.3 me 0.307 Note: same w or w/o ATTiny85
                    pad 8 spec 3.3 me 3.24

                    Voltages on Q1:
                    E - 0.307
                    B - 5.01
                    C - -0.038

                    Comments
                    I seem to be able to get all the pads into spec with the exception of pad 3 (I get 0.0, and spec is 1.6) and pad 7 where I did the surgery (0.3 to 0.4, spec at 3.3).

                    Also, pad 4 is strange. I read 1.52, then wiggle the probe and get 3.24.

                    Is the -0.038 ground plane voltage a problem?

                    Thanks again for your help. This has been a real course in applied SMD technology and electronics.

                    Very best regards,
                    Bill

                    --- In softrock40@yahoogroups.com, "Alan" <alan4alan@...> wrote:
                    >
                    >
                    > ----- Original Message -----
                    > Subject: [softrock40] Re: Need to confirm Si570 distroyed
                    >
                    >
                    > > Thanks for the reminder - There were 8 pads, not 7!
                    > >
                    > > The readings have been changing. Here are the new ones, followed by ones that I get after a few minutes and now:
                    > > Pad 1 - 0.02 volts - 0.02 - 0.00
                    >
                    > Bill,
                    > I've checked, this is normally around 3V3
                    >
                    > > Pad 2 - 3.28 volts - 3.24 - 0.00
                    > > pad 3 - 0.00 volts - -0.03 - 0.00
                    > > pad 4 - 0.00 volts - -0.03 - 0.00
                    > > pad 5 - 0.00 volts - -0.03 - 0.00
                    >
                    > Pads 3,4 should be around 1V5
                    >
                    > > pad 6 - 3.28 volts - 3.24 - 0.00
                    >
                    > Power to Si570.
                    > If you are definite about this there must be a break somewhere between the regulator and Si570. I'd say soldering but just possibly
                    > a crack in the PCB track.
                    >
                    > > pad 7 - 0.42 volts - 0.40 - 0.00
                    >
                    > As before, should be 3V3. Check with ATTiny removed. Check R10 value and it's soldering. Could also be due to fault at Q1. (Yes, and
                    > possibly the Si570)
                    > Until this is right you will not control the Si570.
                    >
                    > > pad 8 - 3.28 volts - 3.24 - 0.00 -
                    >
                    > >All this while pad 5 of the 3.3 regulator says 3.28!
                    > >
                    > > Comments:
                    > >
                    > > When I connected to CFGSR prog, I got a different message. This time on the Test tab, instead of "No Si570 connected or", I now
                    > > get "?? RX Power down ??".
                    > >
                    > > When I do a calibrate, I get "Si570 not powered on?"
                    > >
                    >
                    > Until the voltages are correct do not worry about CFGSR. "RX Power down" means the USB driver is not connected to CFGSR, "Si570 not
                    > powered on" means the Si570 is not connected to CFGSR. But forget CFGSR.
                    >
                    > > I have unable been able to determine why output from my 3.3 regulator varies from 3.28 to 3.24.
                    > >
                    >
                    > This is a very small change. Possibly due to the Si570 not taking current in fault mode.
                    >
                    > > Summary:
                    > > I have been writing this e-mail over a period of about 2 hours. The readings are getting worse (from my perspective). I am trying
                    > > to get consistent measurements. -I am guessing the the Si570 was "sorta" working, and is now failing. >
                    > >
                    >
                    > It is impossible to say right now.
                    > You have the basic 3V3 power fault which is NOT the Si570.
                    > I always suspect soldering, it is not easy and many have declared theirs is good only to find later that resoldering cures a
                    > problem.
                    > And your comment about solder wick makes me think maybe your bit is not ideal. I suggest you look for the pad 6 fault, get a good
                    > bit that will get close to the Si570 and clean as much solder as possible from it.
                    >
                    > 73 Alan G4ZFQ
                    >
                  • Alan
                    ... Subject: [softrock40] Re: Need to confirm Si570 distroyed ... This is a worry, if there is a bridge. ... I think I may be wrong here, maybe should be 0,
                    Message 9 of 20 , Jul 24 12:07 AM
                    • 0 Attachment
                      ----- Original Message -----
                      Subject: [softrock40] Re: Need to confirm Si570 distroyed


                      > You've given me a number of things to try.
                      >
                      > After reheating a number of joints and adding solder to a few (Some pads had gotten insufficient solder, as I soldered the paid
                      > only to avoid bridges), I have been taking measurements:
                      >
                      > pad 1 spec 3.3 me 3.23
                      > Pad 2 spec 3.3 me 3.23
                      > pad 3 spec 0.0 me -.038 Note: ground
                      > pad 4 spec 1.5 me 1.52, but sometimes to 3.23 (connection to pad 8?)

                      This is a worry, if there is a bridge.

                      > pad 5 spec 1.6 me 0.00

                      I think I may be wrong here, maybe should be 0, but other things are not right..

                      > pad 6 spec 3.3 me 3.24 Note: after reheating a few pads, this reading is now stable here
                      > pad 7 spec 3.3 me 0.307 Note: same w or w/o ATTiny85

                      This is a key voltage.
                      Remove the ATTiny and Q1.
                      If it is still about 0V3 then it points to the Si570.

                      It will have to come off. One method is a hot air embossing tool. Cover everything else with foil.
                      You could then send it to the gent who offered to test it.

                      73 Alan G4ZFQ

                      > pad 8 spec 3.3 me 3.24
                      >
                      > Voltages on Q1:
                      > E - 0.307
                      > B - 5.01
                      > C - -0.038
                      >
                    • billsmith952
                      I m about ready to give up on this chip. The only possible way for the chip to be good is if the funny condition on pad 4 is resolved. I did measure the
                      Message 10 of 20 , Jul 24 1:40 PM
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                        I'm about ready to give up on this chip.

                        The only possible way for the chip to be good is if the funny condition on pad 4 is resolved. I did measure the resistance between pad 4 and 8: 1.5+ MegOhms. I don't know if this is sufficient to warrant the chip problems that I have created.

                        The options for removal are (as I can tell):
                        1. Use hot air embossing tool. This would require a gun purchase at $??.??.
                        2. Use desolder paste that will combine with solder to lower the melting temp of the solder so that it could be easily removed.

                        http://store.curiousinventor.com/chip-quikr-surface-mount-desoldering-kit.html
                        Or
                        http://www.ebay.com/itm/Proskit-BGA-Desoldering-Reballing-Repairing-Flux-paste-/360441849209

                        These two methods would preserve the chip for potential salvage.

                        The alternative is to:
                        1. Desolder the 4 SMD caps near the Si570
                        2. Remove as much solder as possible with solder wick
                        3. Use 2 soldering irons (one on each side) and rosin to melt the solder for removal of chip.

                        This last method would require resoldering the 4 SMD caps, in addition to the Si570. It would also probably destroy the chip. The advantage is that I do it with what I currently have.

                        You have been a great help in teaching a number of things about working with SMD component and basic electronics. Thanks.

                        Best regards,
                        Bill


                        --- In softrock40@yahoogroups.com, "Alan" <alan4alan@...> wrote:
                        >
                        >
                        > ----- Original Message -----
                        > Subject: [softrock40] Re: Need to confirm Si570 distroyed
                        >
                        >
                        > > You've given me a number of things to try.
                        > >
                        > > After reheating a number of joints and adding solder to a few (Some pads had gotten insufficient solder, as I soldered the paid
                        > > only to avoid bridges), I have been taking measurements:
                        > >
                        > > pad 1 spec 3.3 me 3.23
                        > > Pad 2 spec 3.3 me 3.23
                        > > pad 3 spec 0.0 me -.038 Note: ground
                        > > pad 4 spec 1.5 me 1.52, but sometimes to 3.23 (connection to pad 8?)
                        >
                        > This is a worry, if there is a bridge.
                        >
                        > > pad 5 spec 1.6 me 0.00
                        >
                        > I think I may be wrong here, maybe should be 0, but other things are not right..
                        >
                        > > pad 6 spec 3.3 me 3.24 Note: after reheating a few pads, this reading is now stable here
                        > > pad 7 spec 3.3 me 0.307 Note: same w or w/o ATTiny85
                        >
                        > This is a key voltage.
                        > Remove the ATTiny and Q1.
                        > If it is still about 0V3 then it points to the Si570.
                        >
                        > It will have to come off. One method is a hot air embossing tool. Cover everything else with foil.
                        > You could then send it to the gent who offered to test it.
                        >
                        > 73 Alan G4ZFQ
                        >
                        > > pad 8 spec 3.3 me 3.24
                        > >
                        > > Voltages on Q1:
                        > > E - 0.307
                        > > B - 5.01
                        > > C - -0.038
                        > >
                        >
                      • Alan
                        Bill, I ve only used a reasonably cheap embossing tool. Others have recommended quick-chip or something named like that. I would not recommend any crude
                        Message 11 of 20 , Jul 24 1:50 PM
                        • 0 Attachment
                          Bill,

                          I've only used a reasonably cheap embossing tool.
                          Others have recommended quick-chip or something named like that.

                          I would not recommend any crude attempt, I usually find that means trying to repair more damage.

                          73 Alan G4ZFQ

                          ----- Original Message -----
                          Subject: [softrock40] Re: Need to confirm Si570 distroyed


                          > I'm about ready to give up on this chip.
                          >
                          > The only possible way for the chip to be good is if the funny condition on pad 4 is resolved. I did measure the resistance between
                          > pad 4 and 8: 1.5+ MegOhms. I don't know if this is sufficient to warrant the chip problems that I have created.
                          >
                          > The options for removal are (as I can tell):
                          > 1. Use hot air embossing tool. This would require a gun purchase at $??.??.
                          > 2. Use desolder paste that will combine with solder to lower the melting temp of the solder so that it could be easily removed.
                          >
                          > http://store.curiousinventor.com/chip-quikr-surface-mount-desoldering-kit.html
                          > Or
                          > http://www.ebay.com/itm/Proskit-BGA-Desoldering-Reballing-Repairing-Flux-paste-/360441849209
                          >
                          > These two methods would preserve the chip for potential salvage.
                          >
                          > The alternative is to:
                          > 1. Desolder the 4 SMD caps near the Si570
                          > 2. Remove as much solder as possible with solder wick
                          > 3. Use 2 soldering irons (one on each side) and rosin to melt the solder for removal of chip.
                          >
                          > This last method would require resoldering the 4 SMD caps, in addition to the Si570. It would also probably destroy the chip. The
                          > advantage is that I do it with what I currently have.
                          >
                          > You have been a great help in teaching a number of things about working with SMD component and basic electronics. Thanks.
                          >
                          > Best regards,
                          > Bill
                          >
                          >
                          > --- In softrock40@yahoogroups.com, "Alan" <alan4alan@...> wrote:
                          >>
                          >>
                          >> ----- Original Message -----
                          >> Subject: [softrock40] Re: Need to confirm Si570 distroyed
                          >>
                          >>
                          >> > You've given me a number of things to try.
                          >> >
                          >> > After reheating a number of joints and adding solder to a few (Some pads had gotten insufficient solder, as I soldered the paid
                          >> > only to avoid bridges), I have been taking measurements:
                          >> >
                          >> > pad 1 spec 3.3 me 3.23
                          >> > Pad 2 spec 3.3 me 3.23
                          >> > pad 3 spec 0.0 me -.038 Note: ground
                          >> > pad 4 spec 1.5 me 1.52, but sometimes to 3.23 (connection to pad 8?)
                          >>
                          >> This is a worry, if there is a bridge.
                          >>
                          >> > pad 5 spec 1.6 me 0.00
                          >>
                          >> I think I may be wrong here, maybe should be 0, but other things are not right..
                          >>
                          >> > pad 6 spec 3.3 me 3.24 Note: after reheating a few pads, this reading is now stable here
                          >> > pad 7 spec 3.3 me 0.307 Note: same w or w/o ATTiny85
                          >>
                          >> This is a key voltage.
                          >> Remove the ATTiny and Q1.
                          >> If it is still about 0V3 then it points to the Si570.
                          >>
                          >> It will have to come off. One method is a hot air embossing tool. Cover everything else with foil.
                          >> You could then send it to the gent who offered to test it.
                          >>
                          >> 73 Alan G4ZFQ
                          >>
                          >> > pad 8 spec 3.3 me 3.24
                          >> >
                          >> > Voltages on Q1:
                          >> > E - 0.307
                          >> > B - 5.01
                          >> > C - -0.038
                          >> >
                          >>
                          >
                          >
                          >
                          >
                          > ------------------------------------
                          >
                          > Yahoo! Groups Links
                          >
                          >
                          >
                        • John Greusel
                          Bill, The embossing guns are about $15- at hobby/craft stores. I ve put together many softrocks and other things with one. Useful to have around even if you
                          Message 12 of 20 , Jul 24 1:53 PM
                          • 0 Attachment
                            Bill,

                            The embossing guns are about $15- at hobby/craft stores.
                            I've put together many softrocks and other things with one.
                            Useful to have around even if you don't use it for assembly.
                            Look at Youtube for examples of people using them.

                            John
                            KC9OJV

                             



                            From: billsmith952 <billsmith952@...>
                            To: softrock40@yahoogroups.com
                            Sent: Wednesday, July 24, 2013 3:40 PM
                            Subject: [softrock40] Re: Need to confirm Si570 distroyed

                             
                            I'm about ready to give up on this chip.

                            The only possible way for the chip to be good is if the funny condition on pad 4 is resolved. I did measure the resistance between pad 4 and 8: 1.5+ MegOhms. I don't know if this is sufficient to warrant the chip problems that I have created.

                            The options for removal are (as I can tell):
                            1. Use hot air embossing tool. This would require a gun purchase at $??.??.
                            2. Use desolder paste that will combine with solder to lower the melting temp of the solder so that it could be easily removed.

                            http://store.curiousinventor.com/chip-quikr-surface-mount-desoldering-kit.html
                            Or
                            http://www.ebay.com/itm/Proskit-BGA-Desoldering-Reballing-Repairing-Flux-paste-/360441849209

                            These two methods would preserve the chip for potential salvage.

                            The alternative is to:
                            1. Desolder the 4 SMD caps near the Si570
                            2. Remove as much solder as possible with solder wick
                            3. Use 2 soldering irons (one on each side) and rosin to melt the solder for removal of chip.

                            This last method would require resoldering the 4 SMD caps, in addition to the Si570. It would also probably destroy the chip. The advantage is that I do it with what I currently have.

                            You have been a great help in teaching a number of things about working with SMD component and basic electronics. Thanks.

                            Best regards,
                            Bill

                            --- In softrock40@yahoogroups.com, "Alan" <alan4alan@...> wrote:
                            >
                            >
                            > ----- Original Message -----
                            > Subject: [softrock40] Re: Need to confirm Si570 distroyed
                            >
                            >
                            > > You've given me a number of things to try.
                            > >
                            > > After reheating a number of joints and adding solder to a few (Some pads had gotten insufficient solder, as I soldered the paid
                            > > only to avoid bridges), I have been taking measurements:
                            > >
                            > > pad 1 spec 3.3 me 3.23
                            > > Pad 2 spec 3.3 me 3.23
                            > > pad 3 spec 0.0 me -.038 Note: ground
                            > > pad 4 spec 1.5 me 1.52, but sometimes to 3.23 (connection to pad 8?)
                            >
                            > This is a worry, if there is a bridge.
                            >
                            > > pad 5 spec 1.6 me 0.00
                            >
                            > I think I may be wrong here, maybe should be 0, but other things are not right..
                            >
                            > > pad 6 spec 3.3 me 3.24 Note: after reheating a few pads, this reading is now stable here
                            > > pad 7 spec 3.3 me 0.307 Note: same w or w/o ATTiny85
                            >
                            > This is a key voltage.
                            > Remove the ATTiny and Q1.
                            > If it is still about 0V3 then it points to the Si570.
                            >
                            > It will have to come off. One method is a hot air embossing tool. Cover everything else with foil.
                            > You could then send it to the gent who offered to test it.
                            >
                            > 73 Alan G4ZFQ
                            >
                            > > pad 8 spec 3.3 me 3.24
                            > >
                            > > Voltages on Q1:
                            > > E - 0.307
                            > > B - 5.01
                            > > C - -0.038
                            > >
                            >



                          • Nick Norman
                            ... The other thing that works is a hot-air paint stripper type gun. But _do_ shield the rest of the board and only use for the minimum time needed, as it is
                            Message 13 of 20 , Jul 24 1:59 PM
                            • 0 Attachment
                              On 24/07/13 21:53, John Greusel wrote:
                              > Bill,
                              >
                              > The embossing guns are about $15- at hobby/craft stores.
                              > I've put together many softrocks and other things with one.
                              > Useful to have around even if you don't use it for assembly.
                              > Look at Youtube for examples of people using them.
                              >
                              > John
                              > KC9OJV
                              >
                              >

                              The other thing that works is a hot-air paint stripper type gun. But
                              _do_ shield the rest of the board and only use for the minimum time
                              needed, as it is a bit of a hammer to crack a nut solution - but works!

                              HTH

                              Nick
                              M0HGU

                              --
                              "Quick, you must come with me, you're in great
                              danger!" "Why?" "Because I'll kill you if you dont."
                              (Sourcery)
                              21:55:01 up 3 days, 12:06, 7 users, load average: 1.53, 1.41, 1.28
                            • billsmith952
                              Thank you all for your suggestions. I will be checking out a hot air embossing gun at Michael s very soon. Bill KC0TBO
                              Message 14 of 20 , Jul 24 2:42 PM
                              • 0 Attachment
                                Thank you all for your suggestions. I will be checking out a hot air embossing gun at Michael's very soon.

                                Bill KC0TBO

                                --- In softrock40@yahoogroups.com, Nick Norman <m6bvj@...> wrote:
                                >
                                > On 24/07/13 21:53, John Greusel wrote:
                                > > Bill,
                                > >
                                > > The embossing guns are about $15- at hobby/craft stores.
                                > > I've put together many softrocks and other things with one.
                                > > Useful to have around even if you don't use it for assembly.
                                > > Look at Youtube for examples of people using them.
                                > >
                                > > John
                                > > KC9OJV
                                > >
                                > >
                                >
                                > The other thing that works is a hot-air paint stripper type gun. But
                                > _do_ shield the rest of the board and only use for the minimum time
                                > needed, as it is a bit of a hammer to crack a nut solution - but works!
                                >
                                > HTH
                                >
                                > Nick
                                > M0HGU
                                >
                                > --
                                > "Quick, you must come with me, you're in great
                                > danger!" "Why?" "Because I'll kill you if you dont."
                                > (Sourcery)
                                > 21:55:01 up 3 days, 12:06, 7 users, load average: 1.53, 1.41, 1.28
                                >
                              • John Greusel
                                Actually it might be worth a try reflowing the solder joints (with the embossing gun) before removing anything. John KC9OJV   ________________________________
                                Message 15 of 20 , Jul 24 2:47 PM
                                • 0 Attachment
                                  Actually it might be worth a try reflowing the solder joints (with the embossing gun) before removing anything.

                                  John
                                  KC9OJV

                                   



                                  From: billsmith952 <billsmith952@...>
                                  To: softrock40@yahoogroups.com
                                  Sent: Wednesday, July 24, 2013 4:42 PM
                                  Subject: [softrock40] Re: Need to confirm Si570 distroyed

                                   
                                  Thank you all for your suggestions. I will be checking out a hot air embossing gun at Michael's very soon.

                                  Bill KC0TBO

                                  --- In softrock40@yahoogroups.com, Nick Norman <m6bvj@...> wrote:
                                  >
                                  > On 24/07/13 21:53, John Greusel wrote:
                                  > > Bill,
                                  > >
                                  > > The embossing guns are about $15- at hobby/craft stores.
                                  > > I've put together many softrocks and other things with one.
                                  > > Useful to have around even if you don't use it for assembly.
                                  > > Look at Youtube for examples of people using them.
                                  > >
                                  > > John
                                  > > KC9OJV
                                  > >
                                  > >
                                  >
                                  > The other thing that works is a hot-air paint stripper type gun. But
                                  > _do_ shield the rest of the board and only use for the minimum time
                                  > needed, as it is a bit of a hammer to crack a nut solution - but works!
                                  >
                                  > HTH
                                  >
                                  > Nick
                                  > M0HGU
                                  >
                                  > --
                                  > "Quick, you must come with me, you're in great
                                  > danger!" "Why?" "Because I'll kill you if you dont."
                                  > (Sourcery)
                                  > 21:55:01 up 3 days, 12:06, 7 users, load average: 1.53, 1.41, 1.28
                                  >



                                • rainerfeldkamp
                                  Hi, At least in Europe we have a little bit time consuming but less intrusive possibility of removing the Si570 since we have or may may get brass tubes having
                                  Message 16 of 20 , Jul 24 3:44 PM
                                  • 0 Attachment
                                    Hi,

                                    At least in Europe we have a little bit time consuming but less intrusive possibility of removing the Si570 since we have or may may get brass tubes having an OD of 10mm (7/16'' should fit) and an ID of 8mm in hardware shops. Similar tubes should be available in the 'inch' world.

                                    Further, most soldering irons in the range of 80 to 150W have soldering tips with a shaft diameter of 7 to 8mm. Cut off the flattened end of an old soldering tip up to the circular portion thereof.

                                    Cut a length of about 25mm (1'') of the brass tube, slit one end thereof over a short length (10 mm), crimp it with pliers onto the remaining shaft portion of the soldering tip so that the tube protrudes about 6 to 10mm beyond and the shaft end (sufficient to take up the height of the Si570 with some clearance not to contact the upper surface of the Si570 with the soldering shaft stub).

                                    For convenience and for better heat transfer heat this construction in the soldering iron and solder the slotted end to the soldering shaft stub. Let it cool down and deform the free end of the tube with the help of pliers to the rectangular shape of the Si570 so that it snugly fits over it.

                                    With this 'tool' which is of course reusable many times, heat the soldering iron until you can melt a little bit of solder on the rectangular end and the inner sides thereof and place it quickly over the Si570 and onto the circuit board.

                                    Softly wiggle the soldering iron until you feel that the Si570 is loose and you will be able to lift it up from the board and shake it out of the tube as quick as possible so that it is not heat damaged.

                                    A beer mug or similar comes in handy to throw the Si570 into it so that you don't loose it.

                                    All three Si570 removed so far with this tool have survived.

                                    73, Rianer DJ6OA


                                    --- In softrock40@yahoogroups.com, Nick Norman <m6bvj@...> wrote:
                                    >
                                    > On 24/07/13 21:53, John Greusel wrote:
                                    > > Bill,
                                    > >
                                    > > The embossing guns are about $15- at hobby/craft stores.
                                    > > I've put together many softrocks and other things with one.
                                    > > Useful to have around even if you don't use it for assembly.
                                    > > Look at Youtube for examples of people using them.
                                    > >
                                    > > John
                                    > > KC9OJV
                                    > >
                                    > >
                                    >
                                    > The other thing that works is a hot-air paint stripper type gun. But
                                    > _do_ shield the rest of the board and only use for the minimum time
                                    > needed, as it is a bit of a hammer to crack a nut solution - but works!
                                    >
                                    > HTH
                                    >
                                    > Nick
                                    > M0HGU
                                    >
                                    > --
                                    > "Quick, you must come with me, you're in great
                                    > danger!" "Why?" "Because I'll kill you if you dont."
                                    > (Sourcery)
                                    > 21:55:01 up 3 days, 12:06, 7 users, load average: 1.53, 1.41, 1.28
                                    >
                                  • Lawrence Galea
                                    HI rainer, would it then get drunk? ________________________________ Da: rainerfeldkamp A: softrock40@yahoogroups.com Inviato:
                                    Message 17 of 20 , Jul 29 2:00 PM
                                    • 0 Attachment
                                      HI rainer, would it then get drunk?


                                      Da: rainerfeldkamp <rainerfeldkamp@...>
                                      A: softrock40@yahoogroups.com
                                      Inviato: Giovedì 25 Luglio 2013 0:44
                                      Oggetto: [softrock40] Re: Need to confirm Si570 distroyed

                                       
                                      Hi,

                                      At least in Europe we have a little bit time consuming but less intrusive possibility of removing the Si570 since we have or may may get brass tubes having an OD of 10mm (7/16'' should fit) and an ID of 8mm in hardware shops. Similar tubes should be available in the 'inch' world.

                                      Further, most soldering irons in the range of 80 to 150W have soldering tips with a shaft diameter of 7 to 8mm. Cut off the flattened end of an old soldering tip up to the circular portion thereof.

                                      Cut a length of about 25mm (1'') of the brass tube, slit one end thereof over a short length (10 mm), crimp it with pliers onto the remaining shaft portion of the soldering tip so that the tube protrudes about 6 to 10mm beyond and the shaft end (sufficient to take up the height of the Si570 with some clearance not to contact the upper surface of the Si570 with the soldering shaft stub).

                                      For convenience and for better heat transfer heat this construction in the soldering iron and solder the slotted end to the soldering shaft stub. Let it cool down and deform the free end of the tube with the help of pliers to the rectangular shape of the Si570 so that it snugly fits over it.

                                      With this 'tool' which is of course reusable many times, heat the soldering iron until you can melt a little bit of solder on the rectangular end and the inner sides thereof and place it quickly over the Si570 and onto the circuit board.

                                      Softly wiggle the soldering iron until you feel that the Si570 is loose and you will be able to lift it up from the board and shake it out of the tube as quick as possible so that it is not heat damaged.

                                      A beer mug or similar comes in handy to throw the Si570 into it so that you don't loose it.

                                      All three Si570 removed so far with this tool have survived.

                                      73, Rianer DJ6OA

                                      --- In softrock40@yahoogroups.com, Nick Norman <m6bvj@...> wrote:
                                      >
                                      > On 24/07/13 21:53, John Greusel wrote:
                                      > > Bill,
                                      > >
                                      > > The embossing guns are about $15- at hobby/craft stores.
                                      > > I've put together many softrocks and other things with one.
                                      > > Useful to have around even if you don't use it for assembly.
                                      > > Look at Youtube for examples of people using them.
                                      > >
                                      > > John
                                      > > KC9OJV
                                      > >
                                      > >
                                      >
                                      > The other thing that works is a hot-air paint stripper type gun. But
                                      > _do_ shield the rest of the board and only use for the minimum time
                                      > needed, as it is a bit of a hammer to crack a nut solution - but works!
                                      >
                                      > HTH
                                      >
                                      > Nick
                                      > M0HGU
                                      >
                                      > --
                                      > "Quick, you must come with me, you're in great
                                      > danger!" "Why?" "Because I'll kill you if you dont."
                                      > (Sourcery)
                                      > 21:55:01 up 3 days, 12:06, 7 users, load average: 1.53, 1.41, 1.28
                                      >



                                    • Jasmine Strong
                                      A much better way of removing these parts is using Chipquik low-melting solder paste. Gob it on liberally around the part, then melt it with the iron; it
                                      Message 18 of 20 , Jul 29 2:15 PM
                                      • 0 Attachment

                                        A much better way of removing these parts is using Chipquik low-melting solder paste.  Gob it on liberally around the part, then melt it with the iron;  it will stay molten long enough that you can remove even large components easily.

                                        -J.

                                        On 29 Jul 2013, at 14:00, Lawrence Galea <galea_lawrence@...> wrote:

                                         

                                        HI rainer, would it then get drunk?


                                        Da: rainerfeldkamp <rainerfeldkamp@...>
                                        A: softrock40@yahoogroups.com
                                        Inviato: Giovedì 25 Luglio 2013 0:44
                                        Oggetto: [softrock40] Re: Need to confirm Si570 distroyed

                                         
                                        Hi,

                                        At least in Europe we have a little bit time consuming but less intrusive possibility of removing the Si570 since we have or may may get brass tubes having an OD of 10mm (7/16'' should fit) and an ID of 8mm in hardware shops. Similar tubes should be available in the 'inch' world.

                                        Further, most soldering irons in the range of 80 to 150W have soldering tips with a shaft diameter of 7 to 8mm. Cut off the flattened end of an old soldering tip up to the circular portion thereof.

                                        Cut a length of about 25mm (1'') of the brass tube, slit one end thereof over a short length (10 mm), crimp it with pliers onto the remaining shaft portion of the soldering tip so that the tube protrudes about 6 to 10mm beyond and the shaft end (sufficient to take up the height of the Si570 with some clearance not to contact the upper surface of the Si570 with the soldering shaft stub).

                                        For convenience and for better heat transfer heat this construction in the soldering iron and solder the slotted end to the soldering shaft stub. Let it cool down and deform the free end of the tube with the help of pliers to the rectangular shape of the Si570 so that it snugly fits over it.

                                        With this 'tool' which is of course reusable many times, heat the soldering iron until you can melt a little bit of solder on the rectangular end and the inner sides thereof and place it quickly over the Si570 and onto the circuit board.

                                        Softly wiggle the soldering iron until you feel that the Si570 is loose and you will be able to lift it up from the board and shake it out of the tube as quick as possible so that it is not heat damaged.

                                        A beer mug or similar comes in handy to throw the Si570 into it so that you don't loose it.

                                        All three Si570 removed so far with this tool have survived.

                                        73, Rianer DJ6OA

                                        --- In softrock40@yahoogroups.com, Nick Norman <m6bvj@...> wrote:
                                        >
                                        > On 24/07/13 21:53, John Greusel wrote:
                                        > > Bill,
                                        > >
                                        > > The embossing guns are about $15- at hobby/craft stores.
                                        > > I've put together many softrocks and other things with one.
                                        > > Useful to have around even if you don't use it for assembly.
                                        > > Look at Youtube for examples of people using them.
                                        > >
                                        > > John
                                        > > KC9OJV
                                        > >
                                        > >
                                        >
                                        > The other thing that works is a hot-air paint stripper type gun. But
                                        > _do_ shield the rest of the board and only use for the minimum time
                                        > needed, as it is a bit of a hammer to crack a nut solution - but works!
                                        >
                                        > HTH
                                        >
                                        > Nick
                                        > M0HGU
                                        >
                                        > --
                                        > "Quick, you must come with me, you're in great
                                        > danger!" "Why?" "Because I'll kill you if you dont."
                                        > (Sourcery)
                                        > 21:55:01 up 3 days, 12:06, 7 users, load average: 1.53, 1.41, 1.28
                                        >





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