This is Planet Money from NPR.

Just a quick warning, this episode contains a phrase that might not be suitable for kids.

Nathan Barton is the kind of guy who likes to solve problems by tinkering around.

I'm an engineer by training, and with engineering you just start building things, measuring things,

paying attention to the outcome, and then take that and do better next time.

Nathan used to design microchips for Texas Instruments, but he brings that same engineering vibe to his new life as a stay-at-home dad outside Portland, Oregon.

If he gets stuck on a problem, he'll just keep working on it and working on it in his mind, breaking it down until he can figure out how all the pieces fit together.

I'm kind of obsessive-compulsive, so I don't let go of things very easily.

A couple years ago, Nathan turned his laser focus to a problem that a lot of us have sadly become intimately familiar with.

Telemarketing phone calls.

His kids had just become twin-agers, so Nathan had gotten them their first cell phones.

But whenever he'd actually try to call them to make plans or ask what they want for dinner or whatever, they wouldn't pick up the phone.

I want to get on them that well that's not the deal, and then they say, well I can't leave the phone on because it rings a lot.

Nathan had gotten these kinds of calls before, but it felt different now that his kids were getting them too.

They were going after his family.

And where before he might have applied his dogged engineering mind to designing a better microchip, all of a sudden he had a new mission.

I felt like it was kind of my job then to make the phone stop ringing.

So Nathan made the first obvious move. He put his kids' numbers on the government's do-not-call list.

The one that tells telemarketers do-not-call these people.

The calls kept coming. The system was not working the way it was supposed to.

But Nathan happened to know that the system offered regular citizens a more powerful tool, an obscure federal law.

He'd used it once before to get the sky to stop sending him junk faxes back when people stole fax machines.

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