Electrical Engineering question , do pedals not protect you from Widow makers?

Discussion in 'Glowing Bottle Tube Amp Forum' started by jomazq, Oct 9, 2019.

  1. jomazq

    jomazq Tele-Meister Silver Supporter

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    maybe a dumb question: if you have a widow maker amp, would pedals protect your from electrocution ? like a buffer pedal before input ? would the 120v be connected through ground side , still ?
     
  2. Speedy454

    Speedy454 Tele-Holic

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    Most likely they will not protect you or isolate you.
    If you get a 'hot' chassis, the voltage will be on the outer ground connector of the chassis, right down the outer ground of the cable, right through the metal chassis of the foot pedal, right through the next outer ground cable, right to your guitar bridge/strings, right to you.
     
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  3. mfguitar

    mfguitar Tele-Holic

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    I think you are more worried about tube voltage, 120 would just tingle a bit :) A wireless setup would be better.
     
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  4. gusfinley

    gusfinley Tele-Holic

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    Please elaborate on "widow maker amp."

    If iy want to be completely sure use one of those "hum bucking" boxes with a signal transformer in it,
     
  5. Mexitele Blues

    Mexitele Blues Tele-Holic

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    You could use an ABY pedal with a ground lift/isolation transformer.
     
  6. ICTRock

    ICTRock Tele-Afflicted

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    all you are doing is temporarily transferring fault to the pedal(s) until those are destroyed and that's no guarantee you still won't get bit as bad as if they weren't there ... it is a poor and equally expensive alternative to doing the right thing.
     
  7. wabashslim

    wabashslim Tele-Holic

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    Yeah, well, 120v can tingle you to death. You're gripping a guitar around the neck with your sweaty left hand and you grab the mic stand with your right - if one or the other is hot your hands can lock on and down goes Frazier. It happens.
     
  8. Wally

    Wally Telefied Ad Free Member

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    they are called widow makers because they have no power transformer or isolation transformer. They run the AC voltage directly to the circuit. They are sometimes called ‘American Five’ circuits....you can add up the first number of the tube designations and it will come very close to equaling the wall voltage back in the day.
    The lower power Silvertone single 6V6 amp-in-a-case guitar rig that came with a short scale, single pickup Danelectro is a widow maker. The amp/case that came with the longer scale, two pickup Dano has 2 x 6V6’s and a power transformer.
     
  9. fakeocaster

    fakeocaster Tele-Afflicted Silver Supporter

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    Make sure that the amp is earthed properly and you won't have a problem.
     
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  10. Wally

    Wally Telefied Ad Free Member

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    Unless an amp has a power transformer or an isolation transformer, earthing does not prevent possibilities of severe shock.
     
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  11. drf64

    drf64 Poster Extraordinaire Silver Supporter

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    Do you have a widow maker amp?
     
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  12. 24 track

    24 track Doctor of Teleocity Silver Supporter

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    I have a pine electronics Pepco widow maker and believe me as nice as that amp sounds the current goes right to chassis , at least pine was kind enough to post the transformer mod on line , I would not trust any amp that was not isolated from the current because in the correct circumstances you are the conduit for the full force of that, notice ther is no transformer on the voltage input

    P1011563.JPG P1011565.JPG P1011566.JPG P1011571.JPG
     
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  13. gusfinley

    gusfinley Tele-Holic

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    At the very least wire up an isolation transformer. I had a "widow maker" table radio on my bench once and it did some WIERD things. I finally wired up an isolation transformer I had laying around after it blew up my AUX out on my mixer!
     
    Last edited: Oct 9, 2019
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  14. LightningPhil

    LightningPhil TDPRI Member

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    It’ll help a lot if earthed properly by providing an easier current path than you do
     
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  15. rolandson

    rolandson Tele-Meister

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    Before the advent of wireless, I would get periodically zapped by the fine wiring that Mr. Gilbert's third grade cooking class students did on the electrical systems of some of our finer establishments...

    So I took my strings and bridge out of the circuit by simply cutting the ground lead to the bridge (actually the trem spring claw on Strats but what the hell), after which I did a thorough shielding job.

    No hum, no zap.
     
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  16. Bill Moore

    Bill Moore Tele-Afflicted Silver Supporter

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    I'm personally more concerned with the 120V zap than I am the high voltage, LOW AMPERAGE bite you get from most tube amps! There is 15 amps minimum available at the wall outlet!
     
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  17. getbent

    getbent Telefied Ad Free Member

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    the pedal won't save you.
     
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  18. peteb

    peteb Friend of Leo's

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    This won’t.






    55BE97BF-EB24-4DC6-9D2F-160DC7BD236C.png



    This will.
    6DC64ACB-8DC7-4DDE-B1A9-0F496230127D.jpeg


    Use a DMM and outlet checker, make sure the amp is grounded or plugged in properly, and then I do not think you can get shocked.
     
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  19. matmosphere

    matmosphere Tele-Meister

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    https://robrobinette.com/Widowmakers.htm

    There is a detailed explanation of how to safely wire this up at the bottom of the page. If you don’t understand it or have no experience working on high voltage electronics then take it to a tech and have them do it. If the amp sounds good and is worth using then it is worth making it safe to use. Otherwise, pitch it and buy something else.
     
  20. tvas22

    tvas22 Tele-Meister

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    My multi-pedal power supply is earthed through the amp - its plug just has a plastic earth pin (I’m in the UK).

    I have wondered how safe this is, as I have picked up quite a large voltage potential with my DMM between my pedals’ case and the amp’s ground when they were on but unplugged. But I assume it’s to cut down on ground loop noise?
     
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