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Direct Current - An Podcast

Episode 8: Ho-Ho-How Holiday Lights Work TRANSCRIPT

(The sound of sleigh bells followed by the Direct Current theme plays.)

(Jingle Yule music plays)

ALLISON LANTERO: Welcome to our holiday edition of Direct Current, I’m Allison Lantero. My co-host Matt Dozier is on jury duty, so in here with me is our other resident holiday enthusiast, Katie Walsh.

KATIE WALSH: I’m so excited to be here. There’s pretty much nothing I like more than decorating for the holidays.

LANTERO: Me either. I watched Elf on repeat for an entire day, after I got mono.

WALSH: I call Thanksgiving “Holiday Kickoff Day” and dress in red and green the very next day.

LANTERO: I went as an elf for Halloween one year, complete with green felt costume and jingle bells.

WALSH: I told my family that I would never live on a street that doesn’t go all out with their holiday decorating.

LANTERO: Speaking of holiday decorations, let’s tell people about what happened when we were decorating yesterday.

WALSH: Can we do it in poem form?

AL: Yes!

(Hall of the Mountain King classical music plays)

NARRATOR: Twas a few weeks before Christmas…

VOICE 1: Hannukah!

VOICE 2: Kwanzaa!

VOICE 3: Festivus!

NARRATOR: Twas a few weeks before the holidays... at En-er-gee,

Allison and Katie were decorating their tree

WALSH: I strung up the lights, but hard as I tried,

Some of the strands would only light up on one side.

LANTERO: I plugged and unplugged, I wiggled the wire,

I twisted some bulbs and began to perspire

WALSH: I was ready to quit, to throw out my elf-hat,

NARRATOR: When along came Dan Wood saying,

DAN WOOD: Let me help with that!

(Hallelujah From Messiah classical music plays)

WOOD: I’ve studied these lights, and I know all their quirks.

Here check out this string, I’ll show you how it works.

(Sugar Plum Fairy Fantasy music plays)

These lights can show us how electric currents flow,

When the circuits are working, the bulbs how they glow!


WOOD: Now, there’s a filament inside of each incandescent,

That heats up and makes the bulb luminescent.


WOOD: When these lights are in a series, as these seem to be,

A single burnt filament can darken the tree.

WALSH: Cuz it breaks the circuit?

WOOD: Yes! That is quite right.

Electricity is blocked, which means there’s no light.

LANTERO: But what about strands that are partially lit?

Is there a problem within that circuit?

WOOD: The answer is yes, but there’s more to be said,

They’re wired in parallel, so just some are dead.

When multiple series are wired together,

They create longer strands, but don’t always work better.

WOOD: Wait, a filament breaks and the whole strand goes bust?

There’s gotta be a better way. Really, there must.

WOOD: There are! They’re called shunts, a helpful invention,

If a filament breaks it preserves the connection.

LANTERO: Then why aren’t they working? Are these just defective?

WOOD: Possibly. Or, from another perspective,

If dead lights aren’t replaced, the rest burn out faster,

That’s a surefire route to a holiday disaster.

WALSH: How do you know if the lights are all dead?

Or if just one single bulb is darkening the thread?

WOOD: Well, first you should make sure that each bulb is in tight,

Give each one a twist, and see if the strand lights.

If nothing will light, a fuse might’ve blown,

Which you can replace all on your own.

There’s a miniature door at the end of the wire,

The fuse nestled inside protects you from fire.

Now slide the door open, and if it’s all black,

Pop in a new one, and then slide it back.

(Jazzy Christmas music plays)

LANTERO: So we looked at the fuses, and tested each shunt,

And also embarked on a loosened light hunt.

But when we tried it again, some still didn’t light.

WALSH: This is taking forever. We’ll be here all night!

WOOD: Now don’t worry Katie, there’s more tricks up my sleeve,

You really should hang up some new LEDs.

LED lights are stronger, use less energy;

They also last longer on our homes and our trees.

(Joyful Deck the Halls music plays)

NARRATOR: From out of his sleeve came a long string of lights,

He plugged it right in, and the tree shined so bright!

The lights how they sparkled! The tree looked so merry!

Dan winked and he smiled, like a sugar plum fairy.

They heard him exclaim ‘ere he walked out of sight

WOOD: Happy holidays to all and to all working lights!

(Swingin' Jazz version of Jingle Bells plays)

WALSH: Now our tree’s covered in light emitting diodes,

Let’s thank some folks for help on this episode.

LANTERO: Direct Current’s produced by me, Simon and Matt,

Art by Cort, help from Paul, Atiq, Ernie and Pat.

WALSH: Thanks to Marissa  and Team Public Affairs,

For all of their edits, critiques and blank stares.

LANTERO: A big thank-you to Katie, my favorite guest host,

And to Dan Wood, for teaching us the most.

WALSH: Direct Current is from the Department of En-er-gee,

Produced out of our office in Washington D.C.

LANTERO: is where you should go,

To get more information about this very show.

Thanks for all your help, Katie.

WALSH: Anytime, Allison.

LANTERO: Think it’s time to take the Santa hat off now?

WALSH: No, this is never coming off.

LANTERO: Thanks for listening!

(Sparkle sound effect)



Why do holiday lights burn out all the time? We find out the answer, and do it in rhyme.

How Do Holiday Lights Work?


If the podcast didn't answer your question, or you just want to see some of the cool graphics we've made about holiday lights, this is the blog for you!