Fedtro Vacuum Tube Tester to USB Conversion





Introduction: Fedtro Vacuum Tube Tester to USB Conversion

About: I love Technology with a passion its constantly changing on a daily basis. This phenomenon is so overlooked by the most of the world we use it on a daily and the majority of the world is completely oblivious...

Well, I basically took the tester and removed the battery spacers out that were obsolete

Due to the size of the battery which was slightly smaller by a 5th of it. I then took an old Phone usb and usb adapter charger and clipped the micro usb connection off exposing the internal wires I then soldered the negative to negative and positive to positive and ran several test to confirm if is usefulness it worked like a charm.

tested the tester by plugging it into the outlet and computers even my car and it worked :)

so here you go enjoy

a Fedtro Vacuum tube tester circa 1966

To USB Conversion.



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    14 Discussions

    this isnt a real tube tester

    it is a fillament checker

    it checks the fillamtents


    11 replies

    i know but i like to warn people about it
    becaus i was fooled by it once (when i just started working with tubes)

    To bad the technology is so great even at its age it is so much fun the image you have as your avatar what is that

    it is my firsth oscilloscope
    i got it for free from a co worker
    i had to dismantle it affter a year of service
    it stoped working

    omg I would work on it if it was mine. I actually had a hughes mitchell VFO i purchased online circa 1939 it was pretty busted up but I fixed it up really nice bought it for 90 sold it for 200.

    is that a vintage oscilliscop? man its a beautiful piece

    cant really tell without my glasses

    You are both right to a certain degree, it is technically a filament continuity tester, the most likely part of a vacuum tube circuit to fail. More electronic circuitry is required to determine gain, leakage, and other useful information about a tube (valve for our Brit friends). My teenage buddy and I used to make these back in the '60's to test tubes from old television and radios we salvaged. For more comprehensive data, we would take them to a local food store which had the big console type tube tester that would check all parameters. I recall we used the venerable #47 6.3 volt mini- lamp as the indicator. That jeweled lens cap is a keeper, they don't make 'em like that any more.