Romantic Glow of the Electron Valve




Nerdmance is in the air! This is a tongue-in-cheek romantic gift for my dear, sweet, long suffering wife.

Dig through your "in progress" electronics bin and find some long forgotten project to resurrect as cheeky nerd gift.

In this case, I'm using a fried data logger, an old electron tube, and a slow color changing LED.

Step 1: Gather Your Parts!

1- Pick out a complex looking, dead PCB. Optionally, have your year-old daughter pick it for you.

2- Choose a suitably sized electron valve (vacuum tube) from your hoard. Don't be shy; you KNOW you'll never use them for anything, especially that DIY tube amp you are going to build next year.

3- Grab a 3V coin cell battery and holder. Keep the coin cell away from sticky-pawed-one-year-olds.

4- Grab a slide switch.

5- Check your stock of self cycling RGB LEDs. These things are awesome, because you don't need a micro-controller to get them to change colors. They do it by themselves. Because magic.

Step 2: Assemble Your Parts!

The 3V coin cell hits a sweet spot for LEDs. It's just the right voltage so that you don't need a current limiting resistor to protect the LED.

Here's how to wire it.

1-Tuck the LED under the valve, so it'll look like the valve is glowing romantically.

2- Wrap solid core wire around the shaft of a screwdriver, this will give you a lovely yuletide bomb-making aesthetic.

3- Solder the long lead of the LED (positive) to the positive of the coin cell holder. We are not going to lessen ourselves by devolving into a conventional current versus electron flow debate. Put it out of your mind.

4- Solder the short lead of the LED (negative) to the end pin of the slide switch.

5- Solder the middle pin of the slide switch to the negative of the coin cell holder.

6- Solder, or hot snot the vacuum tube to the PCB board.

7- Install the battery, turn on the slide switch and make sure it works. You will know it works by the romance that the vacuum tube emits. Should you be in the presence of strangers, be mindful not to get twitterpated.

8- CLICK ON THE GIF OF THE GLOWING TUBE! It took me a longer to make the animated GIF than to build the nerdmantic light. This is what it looks like if you got it right!



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    6 Discussions


    4 years ago on Introduction

    that tube can do so much better stuff

    even if you connected the fillaments without the led

    it would look nicer

    2 replies

    pfff easy

    to bad the battery wont last one hour

    you know what i have a display that already can do that

    i tried it

    and my battery was to empty to power it

    it worked on 2 AA battery's


    4 years ago on Introduction

    You should seriously do an instructable on making a tube amp!


    4 years ago

    I hate to use the word 'adorable' but I'm afraid I must. This is ADORABLE! Total nerd love, doesn't get any more cute!

    1 reply