This Little Amp Is Trying to Kill Me and My Girlfriend

Discussion in 'Shock Brother's DIY Amps' started by ArcticWhite, May 22, 2020.

  1. ArcticWhite

    ArcticWhite Tele-Holic

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    I'm not sure what you mean.
    Can you elaborate?
    The only way I've seen PTs grounded is through a death cap..
     
  2. 985plowboy

    985plowboy Friend of Leo's

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    OP
    You do state in the original post that you plugged it into an ungrounded 3 prong outlet in your garage.
     
  3. GoldDeluxe5E3

    GoldDeluxe5E3 Tele-Afflicted Silver Supporter

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    Strictly speaking, misquoting someone is not rude, it's simply a mistake. I have edited my post to reflect your quote perfectly. Now, how about my theory about the girlfriend?
     
  4. ArcticWhite

    ArcticWhite Tele-Holic

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    I didn't say what was quoted.
    Can we please stick to the amp that is trying to kill me?
    Thanks
     
  5. The Ballzz

    The Ballzz Tele-Afflicted

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    Mr @ArcticWhite
    Its not the amp trying to kill you, its YOU trying to kill you! And you can certainly call me rude too after you hear what I have to say, but facts is FACTS! How you've gained enough knowledge to have "built this little 7 watt guitar amp out of a Silvertone organ amp" and not explicitly learned basic safety rules and/or choose to ignore them is beyond me! First, you have a home modified/built amplifier of questionable lineage, with its mains power cable connected completely improperly. Next, you have and use an outlet that you claim "is wired correctly with the exception of the lack of a ground." Anyone who does not clearly get how and why both that statement and outlet are absolutely incorrect, should not be working on and inside electrical/electronic gear! Just the issues I presented in this post are enough to create very dangerous and yes deadly conditions!

    I wish you a long, happy and healthy life, but unless you change your obviously cavalier attitude towards the importance of safety, I don' expect you to honor my wish! There is a very good reason we don't often hear stories from those who have ignored standard safety practices! SAFETY IS IMPORTANT, AND YOU SHOULD PAY ATTENTION TO IT!

    You Only Get To Die Once In This Lifetime!
    Gene
     
  6. tvas22

    tvas22 Tele-Meister Silver Supporter

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    Have you tested for continuity between each of your tag board terminals and ground? One of those might be shorted. A couple of them look really close to the chassis but it’s hard to tell on the pic.

    There’s a few points where it looks like some of the components might be making contact too - the resistor on pin 6 on the tube at top left of the photo.
     
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  7. voskarp

    voskarp Tele-Holic

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    Amps don't kill people, people... using them with ungrounded outlets may do.
     
  8. Hari Seldon

    Hari Seldon Tele-Meister

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    I'm astounded that almost all postings go into some details, but no one brings up the fact that this whole amp is an utter mess.
    I've rarely seen such sloppy workmanship. Lots of cold solder joints and blank wires.
    I wouldn't dare to bring this thing near a power source.

    Messing about like that is incompetent and careless, and the consequences can be fatal.
    This amp must be completely reconstructed with proper solder joints, isolated wires and careful layout before plugged in.
    (I'm glad somebody commented the ungrounded outlet.)
     
  9. Jimclarke100

    Jimclarke100 Tele-Afflicted

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    In my opinion, using the amp ungrounded is dangerous - that is whether the lack of ground is in the amp plug or in the socket is irrelevant.

    Basically it’ll mean your live and neutral will float at some unknown points and the chassis ground will not be true ground.

    This then means that you will be the route to ground, or maybe not if you are wearing insulated shoes - in the latter case, when your girlfriend hugged you she provided the ground.

    Guys have been killed on stage by this....

    Always use the amp properly grounded.
     
  10. tubelectron

    tubelectron Tele-Afflicted

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    Just a question @ArcticWhite : did you tested your amp on a 3-prong wall socket ? - I mean with GND connection to a differential circuit breaker ? If the circuit breaker opens, that means that there's a leak to the GND :

    - or a bare wire of some sort somewhere.
    - or power transformer with defective insulation.

    Moreover, it is often difficult to check an insulation leak problem on a transformer, since it is over 40 to 60M, that is to say way over the DMM Megohm ranges.

    On an audio power or output transformer, the dielectric rigidity (Hi POT) can be 1500/2000VDC between windings and between GND, with a winding to GND insulation over 5000 to 10000M.

    -tbln
     
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  11. Asmith

    Asmith Friend of Leo's

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    Someone correct me if I'm wrong.

    If you're using a transformer to isolate the DC from the wall and not giving it a reference again then the circuit and chassis will be floating. The fix is to use a grounded outlet when the circuit is connected to the chassis!

    I have a little 9V battery operated Marshall ms4 and when the back of my hand or inner side of my elbow touched the strings I'd feel a tingle.
     
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  12. sds1

    sds1 Tele-Afflicted

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    Wow this thread certainly brought in some randos.

    That is all.
     
  13. sds1

    sds1 Tele-Afflicted

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    Not that is not all.

    Reckon because it's severely off topic, irrelevant, and rude.

    This is all nonsense, not at all rooted in a practical understanding of electricity or tube amps, or even general troubleshooting methodology.

    This advice and poster can all be safely ignored.

    The OP brought it up himself. Too bad you chose to focus on less relevant things.
     
  14. Hari Seldon

    Hari Seldon Tele-Meister

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    Must have touched some nerves...

    (Better this than touching that amp ;- )
     
  15. sds1

    sds1 Tele-Afflicted

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    Your very own Mission Accomplished moment.
     
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  16. tubegeek

    tubegeek Tele-Holic

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    The OP is concerned because his DIY amp shocked him. (You can read the thread title for some confirmation if you think I'm misinterpreting this.)

    Surely a review of the construction, as shown in the pics provided by the OP, most likely for this exact purpose, is relevant.

    Please ignore me, too, then - I'd hate to disturb you, @sds1 .
     
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  17. sds1

    sds1 Tele-Afflicted

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    You're not disturbing me at all, I find your posts to be both friendly and helpful.

    "Your build is ugly, solder joints suck, no wonder it doesn't work. Oh, also what those other guys said"

    You could copy/paste that trollish nonsense into any build thread here, it would continue to be just as rude and just as useless.

    I think most ppl here can see the difference between your posts and his.
     
    Last edited: May 23, 2020
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  18. tubegeek

    tubegeek Tele-Holic

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    Well, I guess that makes sense, and, thanks for the kind words. And for explaining what was bugging you.

    Moving on....
     
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  19. Hari Seldon

    Hari Seldon Tele-Meister

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    Express you opinion, but don't misquote.
    And it's you who's getting personal from the beginning.
    So far no useful comment from you.
     
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  20. sds1

    sds1 Tele-Afflicted

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