5e3 build, filament/"pilot" light questions

Discussion in 'Amp Tech Center' started by twst1up, Aug 30, 2020.

  1. twst1up

    twst1up TDPRI Member

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    Hey now! Been building a mojotone kit.

    I've built a pedal, ive wired guitars, thats it. I can follow the wiring diagram that came with the kit but can't read schematics.

    I've been testing continuity along the way to make sure my soldering connections are good.
    I'm almost done, one of the things I've saved for last is the filament wires going from the pilot light to the power tube, jumping down to the preamp tubes. as I'm working left to right I test continuity. I work my way down to the last tube and I check continuity all the way back to the pilot light. So I have my two leads left for the last tube socket.

    Then, and I dont know how exactly (or why I checked), I discover both leads have continuity.

    I tracked back to the pilot light only to discover each lug of it has continuity ss well. Did I goo it up wirh solder , I wonder? Don't look like it.

    Then it occurs to me after a while to remove the light bulb!!! That'll break the continuity!!!.

    Nope. Damn

    For ****s and gigs I test and see rheres continuity between the two green leads from the transformer. hmmm

    But there's still continuity between the lugs on the pilot light

    Soooo.....is all this continuity correct or do I have a bum light?

    Should there be continuity on the leads from the transformer? (I'm guessing yes but dont know)
     
  2. Jon Snell

    Jon Snell Tele-Holic

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    There should be continuity between the pilot light contacts, if incandescent. It is wired across the 6.3volt heater winding. If LED there will be a diode and resistor in the circuit.
     
  3. robrob

    robrob Poster Extraordinaire Ad Free Member

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    Going from 120 or 240v down to 6.3v means the 6.3v winding is a relatively short length of wire wrapped around the iron core so it will usually give you a continuity beep from your meter. You are probably good to go.
     
  4. Paul G.

    Paul G. Friend of Leo's

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    As others have noted, the 6.3V winding is a short piece of wire. There should be almost zero resistance between the legs.
     
  5. twst1up

    twst1up TDPRI Member

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    Thanks all
     
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