Hush Those Old-Fashioned Phones

Most people hate unsolicited calls, and it’s worse in the dead of night when we’re all trying to sleep. Smartphones are easy to configure to block nuisance calls, but what if you need a solution for your Plain Old Telephone System (POTS)? [Molecular Descriptor] has built a system to invisibly stop landline phones ringing after hours.

The basic principle relies on an analog circuit that detects the AC ringing signal from the phone network, and then switches in an impedance to make the phone company think the phone has been picked up. The circuit is able to operate solely on …read more

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Banana Phone Blocks Robocalls

Despite the implementation of the National Do Not Call Registry in the US (and similar programs in other countries), many robocallers still manage to get around the system. Whether they’re operating outside the law somehow (or they simply don’t care about it) there are some ways you can take action to keep these annoying calls from coming through. [Alex] is among those to take matters into his own hands and built a specialty robocall-blocking device.

Based on a Raspberry Pi, the “Banana Phone” is able to intercept incoming calls on standard land lines or VoIP phones. After playing a short …read more

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GSM Sniffing on a Budget with Multi-RTL

If you want to eavesdrop on GSM phone conversations or data, it pays to have deep pockets, because you’re going to need to listen to a wide frequency range. Or, you can just use two cheap RTL-SDR units and some clever syncing software. [Piotr Krysik] presented his work on budget GSM hacking at Camp++ in August 2016, and the video of the presentation just came online now (embedded below). The punchline is a method of listening to both the uplink and downlink channels for a pittance.

[Piotr] knows his GSM phone tech, studying it by day and hacking on a …read more

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ZeroPhone gives Smartphones the Raspberry (Pi)

There are several open source phones out there these days, but all of them have a downside. Hard to obtain parts, hard to solder, or difficult programming systems abound. [Arsenijs] is looking to change all that with ZeroPhone. ZeroPhone is based upon the popular Raspberry Pi Zero. The $5 price tag of the CPU module means that you can build this entire phone for around $50 USD.

The radio module in the ZeroPhone is the well known SIM800L 2G module. 2G is going away or gone in many places, so [Arsenijs] is already researching more modern devices. An ESP8266 serves …read more

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ZeroPhone gives Smartphones the Raspberry (Pi)

There are several open source phones out there these days, but all of them have a downside. Hard to obtain parts, hard to solder, or difficult programming systems abound. [Arsenijs] is looking to change all that with ZeroPhone. ZeroPhone is based upon the popular Raspberry Pi Zero. The $5 price tag of the CPU module means that you can build this entire phone for around $50 USD.

The radio module in the ZeroPhone is the well known SIM800L 2G module. 2G is going away or gone in many places, so [Arsenijs] is already researching more modern devices. An ESP8266 serves …read more

Continue reading ZeroPhone gives Smartphones the Raspberry (Pi)

Smartphone Case For The Retro Gamer

A well-designed phone case will protect your phone from everyday bumps with only as much style flair as you’d like. While protection is usually the only real function of a case, some designs — like [Gabbelago]’s Emucase — add specific utility that you might not have known you needed.

Contrary to most cases, the Emucase fits over your phone’s screen, and the resulting facelift emulates the appearance of a Game Boy for easier — you guessed it — Game Boy emulation play on your smartphone.

Cannibalizing a USB SNES gamepad for its buttons and rubber contact pads, Gabbelago then threaded …read more

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Blynk with Joy

Last time, I talked about how my storage situation and my cheap nature led me to build an RC joystick controller with a cell phone app and an ESP8266. The key to making this easy was to use the GUI builder called Blynk to make a user interface for an Android or Apple phone. Blynk can communicate with the ESP8266 and makes the project relatively simple.

ESP8266 and Arduino IDE

The ESP8266 Blynk code is straightforward. You do need to set up the Arduino IDE to build for the ESP8266. That can vary by board, but here’s the instructions for …read more

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Payphone Boombox Straight Out of the 1990’s.

Due largely to the overwhelming dominance of mobile phones, payphones are a sometimes overlooked relic from the 90’s and earlier eras. While seldom seen out in the wild these days, they can however still be acquired for a moderate fee — how many of you knew that? Setting out to prove the lasting usefulness of the payphone, Instructables user [Fuzzy-Wobble] has dialed the retro spirit way past eleven to his ’90 from the ’90s’ payphone boombox.

Conspicuously mounted in the corner of his office, a rangefinder sets the phone to ringing when somebody walks by — a fantastic trap for …read more

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The Joy of the ESP8266 and Blynk

I’ll admit it. I can be a little cheap. I also find it hard to pass up a bargain. So when I saw a robot kit at the local store that had been originally $125 marked down to $20, I had to bite. There was only one problem. After I got the thing home, I found they expected you to supply your own radio control transmitter and receiver.

Normally, that wouldn’t be a problem but lately… let’s just say a lot of my stuff is in storage and I didn’t have anything handy. I certainly didn’t want to go buy …read more

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Star Trek Phone Dock Might as Well Be From Picard’s Night Stand

Star Trek is often credited with helping spur the development of technologies we have today — the go-to example being cell phones. When a Star Trek April Fool’s product inspires a maker to build the real thing? Well, that seems par for the course. [MS3FGX] decided to make it so. The 3D printed Star Trek-themed phone dock acts as a Bluetooth speaker and white noise generator. The result is shown off in the video below and equals the special effects you expect to find on the silver screen.

Taking a few liberties from the product it’s based on — which …read more

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