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  • #31
    Originally posted by Enzo View Post
    Oh I am all for you figuring it out, I am interested too.

    I was thinking about cleaning up the mess, it seems that just rebuilding might make more sense. But DO solve the problem first.
    And I am all about gutting it and rebuilding it right on an eyelet board. As soon as we figure this out, that is exactly what I'll do. The soldering is amateur and as pointed out above, some of the wiring and component placement are poorly implemented.

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    • #32
      Originally posted by Tone Meister View Post
      And I am all about gutting it and rebuilding it right on an eyelet board. As soon as we figure this out, that is exactly what I'll do. The soldering is amateur and as pointed out above, some of the wiring and component placement are poorly implemented.
      Don't underestimate the resistance of a bad solder joint.

      nosaj

      Just thinking out loud...using a scope at the input then input of 12ax7 and so on. You could see the signal size increase and at some point see it choke out.
      soldering stuff that's broken, breaking stuff that works, Yeah!

      Comment


      • #33
        Originally posted by Randall View Post
        "Also, the NFR is 1.4K and not 22K."

        A few posts earlier you said it was 22k measured out of circuit?
        Yes, it was under heatshrink so I had measured it in cirxuit amd got 1.4k. Out of circuit it measures 22k.

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        • #34
          Originally posted by The Dude View Post
          There are lots of ways to lower output. Also check to see if they are running the 6V6 in triode mode. Is the screen connected like the original schematic?
          6V6 is wired normal as in that.photo

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          • #35
            Originally posted by Tone Meister View Post
            6V6 is wired normal as in that.photo
            And the volume pot?
            nosaj
            soldering stuff that's broken, breaking stuff that works, Yeah!

            Comment


            • #36
              Originally posted by nosaj View Post
              Don't underestimate the resistance of a bad solder joint.

              nosaj

              Just thinking out loud...using a scope at the input then input of 12ax7 and so on. You could see the signal size increase and at some point see it choke out.
              The amp works fine and sounds fine. It was purposely built for 1 watt output but the new owner (my buddy) now wants full output.

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              • #37
                Originally posted by nosaj View Post
                And the volume pot?
                nosaj
                The volume pot is 1 Meg audio taper, switched

                Click image for larger version

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                • #38
                  Originally posted by Tone Meister View Post
                  The amp works fine and sounds fine. It was purposely built for 1 watt output but the new owner (my buddy) now wants full output.
                  Scope might make it faster and easier to see the signal changes throughout the amp. IT's being choked or throttled at 1 watt output somewhere
                  nosaj
                  soldering stuff that's broken, breaking stuff that works, Yeah!

                  Comment


                  • #39
                    Originally posted by nosaj View Post
                    Scope might make it faster and easier to see the signal changes throughout the amp. IT's being choked or throttled at 1 watt output somewhere
                    nosaj
                    https://music-electronics-forum.com/...ad.php?t=48333

                    I don't have a scope at present. Mine was killed over the summer. Got one incoming, but not today.

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                    • #40
                      Originally posted by Tone Meister View Post
                      https://music-electronics-forum.com/...ad.php?t=48333

                      I don't have a scope at present. Mine was killed over the summer. Got one incoming, but not today.
                      And the value of the input resistors?
                      nosaj
                      soldering stuff that's broken, breaking stuff that works, Yeah!

                      Comment


                      • #41
                        In the first picture in post #20, there looks to be a 100 ohm resistor (about middle of pic) going to a pin of the 5Y3. Can you tell us if it is indeed 100 ohm and where it actually goes.

                        Edit: Or maybe it just looks like 100 ohm in the pic and it's actually a 10K?
                        Last edited by The Dude; 01-30-2019, 02:05 AM.
                        "I took a photo of my ohm meter... It didn't help." Enzo 8/20/22

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                        • #42
                          Originally posted by The Dude View Post
                          In the first picture in post #20, there looks to be a 100 ohm resistor (about middle of pic) going to a pin of the 5Y3. Can you tell us if it is indeed 100 ohm and where it actually goes.

                          Edit: Or maybe it just looks like 100 ohm in the pic and it's actually the 10K?
                          That is a 10K dropping resistor and it goes from the 5Y3 to the 6V6 screen

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                          • #43
                            Originally posted by nosaj View Post
                            And the value of the input resistors?
                            nosaj
                            Both are 68K. Blue, Gray, Orange

                            Click image for larger version

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                            • #44
                              Originally posted by Tone Meister View Post
                              Both are 68K. Blue, Gray, Orange

                              [ATTACH=CONFIG]52281[/ATTACH]
                              Ok I'm counting 4 resistors out of 12 or so that have been measured. Almost halfway there, might as well start measuring them all and making your own schematic for this one.

                              nosaj
                              soldering stuff that's broken, breaking stuff that works, Yeah!

                              Comment


                              • #45
                                Leadfree solder + somebody who can't solder = mess.

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