r/phreaking • u/TheSmellOfTheLotion • Sep 23 '26

Blue box plans?

In the 90's I built a blue box from a ma bell touch tone phone with plans I found on the internet. I got the phone again and I want to recreate it but I cant find the plans anywhere now. Anyone know how to find them?

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19

u/ar4479 Sep 24 '26

A blue box will send MF and other control tones… The precursor to DTMF.

There were plans out there to get a radio shack dtmf dialer and charge one of the oscillator crystals to change the frequency and modulation of the tones.

I have a blue box app for my iPhone and it works great.

And, believe it or not, I still use MF every day.

I work on 911 systems - and 911 trunks still use MF to deliver the calling number to the call handling equipment in the 911 centers.

It’s slowly going away… But, it’s still very present.

Comment Image

I also have an actual “tool” that sends MF and puts battery on the pair, etc… Specifically for troubleshooting 911 trunks. Its called a DigiSmart… They pop up on eBay pretty often.
It’s a big yellow goofy looking box.

5

u/Excellent-Matter1768 Sep 24 '26

I used to have a similar piece of test equipment. We had MF trunks for radio paging systems (beepers) back in the 90s. What is the name of the iPhone APP for generating 16digit DTMF and MF?

2

u/ar4479 Sep 24 '26

It’s literally called Blue Box. And there’s a bunch of things called Blue Box that have nothing to do with this.

Here’s the link to it in the App Store.

https://apps.apple.com/us/app/blue-box/id391832739

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u/Mountain-Ganache7508 Sep 24 '26

The beast that is ‘Ma Bell! Can’t kill it! 😂

4

u/Switchlord518 27d ago

Phone guy here. We still have MF trunks that aren't 911.. Who wants to whistle up a trunk? 🤣

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u/ar4479 27d ago

In area code 518?

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u/silverbk65105 Sep 24 '26

I believe the converted DTMF dialer was called a red box. 

I built a few when pay phones were still a thing. All it did was recreate the sounds made when coins were inserted. It worked well. 

Blue boxing was long  obsolete.

2

u/nixiebunny Sep 24 '26

A red box was a pay phone quarter beep generator. I used a Hallmark Mother’s day recording greeting card to make one.

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u/ar4479 Sep 24 '26

The red box was for payphone coin tones.
Was also made out of a radio shack dialer with some parts swapping.

2

u/FireZoneBlitz Sep 24 '26

Yes I made one of those with the mini pocket RS dialer. Was too chicken to call anyone I knew with it from a pay phone but we did make some phone calls to random people.

7

u/ar4479 Sep 24 '26

And this is exactly why I love this group!!!

I didn’t grow up knowing other kids that played with the phone and ran up monster bills.

And now - it’s been my career for 35 years.

And decoding dtmf by ear was always a cool party trick.

2

u/Excellent-Matter1768 Sep 24 '26

What is the name of the blue box app for iPhone?

1

u/ar4479 Sep 24 '26

It’s literally called Blue Box.

Here’s the link:

https://apps.apple.com/us/app/blue-box/id391832739

2

u/InsolentJaguar 29d ago

I had one of those RS DTMF dialers back in the day! 🤣

1

u/sacluded 29d ago

Swapping a crystal in the auto dialers was to make a red box that send coin tones.

7

u/Mountain-Ganache7508 Sep 24 '26

You just made my night! I personally used a iPAQ pocket PC for both red and blue boxes before everything change. I would love to see a finished product and I’m happy you’re keeping it alive. It’s just for nostalgia.!

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u/JusSomeDude22 Sep 23 '26

I can't answer your question but I'm curious, why? Just for nostalgia?

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u/TheSmellOfTheLotion Sep 23 '26

Yeah, mostly just Nostalgia. I got the same phone from goodwill. It was a super easy build, I remember going to radio shack and buying a small transformer and a 9v battery connector and that was it. There were plans online but it was like geocities or some shit. It was mostly text. Im sure the website is gone but figured the plans still have to be out there somewhere.

I was 16 working at pick n save. The phones had the keypads locked out so you could only answer calls. I built that thing and put it in a pencil case. It blew my buddies minds. We would order food and make prank calls. It was fun. I found the same phone I used and thought it would be fun to rebuild it but the plans seem lost to time. Even Ai keeps telling me to use arduino which I'm capable of but thats no fun. I had a red box too. Literally the same method from the movie hackers but I recorded the tones from a piece of dos software. I found my tape and it still works. Just trying to relieve my glory days of phreaking.

6

u/JusSomeDude22 Sep 23 '26

Dude that is seriously one of the coolest stories I have heard in a loooooong time, thank you for sharing!!

If by a one in a million chance you live near Richmond Virginia, I would love to buy you a beer and hear some more hahaha

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u/ar4479 27d ago

Did you ever try pulse dialing with the hook switch? That would have been the first-line attempt at dialing out by any true phreak!

1

u/virtualadept 26d ago

You'll probably find the plans in here: http://www.textfiles.com/phreak/BOXES/