Candlestick Phone Goes Modern.

[Adam Ben-Dror] recently tipped us off to a project that he worked on recently. In this build he gutted an old candlestick-style phone and added modern technology to make it work as a cordless phone. We really liked this project because he married together new and old technology into an elegant package. There are a few hacks that he had to perform to get this to work. One was converting the rotary pulses into DTMF tones. The other was making the cordless phone that he gutted recognize when the phone was on or off of the hook.

Details of his build after the break. Continue reading “Candlestick Phone Goes Modern.”

Making A Bluetooth Headset Into A Wireless Music Streaming Device

This bluetooth headset hack, although simple, may provide some hacking inspiration. Turning a Bluetooth headset into a wireless input for one’s stereo is definitely something that makes one think “why didn’t I think of that?” It’s also good if you’ve got a tight hacking budget as there’s not a lot of stuff to buy.

In addition to a possibly broken headset, a 3.5mm stereo plug and some wires are needed for this. Throw in some tools that every good hacker should have around like a soldering iron and glue gun and you’re ready to get started. [Dex] does a good job of describing the process, from disassembling the headset to wiring the stereo plug to it. When making the conversion, one must remember to bridge the left and right output channels, as most headsets only output a mono signal.

There’s not a whole lot else required to do this hack.  Could be a good beginner project. For another Bluetooth-based hack using scrounged equipment, check out this Cellphone controlled retro-radio hack.

A Cellphone Based Interactive Voice Response System

We’re all familiar with IVRS systems that let you access information using a touch-tone telephone. [Achu Wilso] built his own version which uses a cellphone, microcontroller, and computer.

The cellphone is monitored by an LM324 op-amp with an attached 555 timer chip. When a call comes in the voltage on the headphone output goes high, activating the timer circuit. If it goes low and does not go high again for about 25 seconds the call will be ended. Each incoming touch tone acts as a keepalive for the circuit.

An MT8870 DTMF (touch tone) decoder chip monitors the user input. An ATmega8 microcontroller grabs the decoded touch tones from that chip, and pushes them to a PC via USB. The PC-side software is written in Python, using MySQL bindings to access database information. eSpeak, the open source speech synthesizer software is used to read menu and database information back to the caller.

Not a bad little system, we wish there was an audio clip so we could hear it in action.

Bluetooth Wristwatch Based On An Arduino

We hate to admit it, but we missed out on the TI Chronos watch deal last week. While we’re still a little bit burned over the fact that these watches sold out so fast, [Ahmet] sent in his Open Source Bluetooth Watch and we’re thinking this could eventually be a decent replacement.

The watch is built around an Arduino Pro Mini, a scavenged Nokia LCD, and a BlueSMiRF Gold. The Bluetooth connects to a Nokia N900 with a little Bluetooth client app [Ahmet] wrote. He also wrote a small GUI for the watch’s LCD display. Afterwards, he was able to display missed calls, new email, and is now working on support for changing songs on his N900’s media player.

Admittedly, a little work needs to be done on the enclosure. Still, the potential for this watch is much greater than the iPod as a watch project we saw last year. Right now, we’re thinking about what could be added to [Ahmet]’s watch. An accelerometer would probably be on the top of our list, but if you have any ideas feel free to leave them in the comments.

Check out the walk through of the watch’s functions after the break.

Continue reading “Bluetooth Wristwatch Based On An Arduino”

Hacking A2DP Support Into An Old Car Stereo

a2dp_tape_deck_retrofit

[Roofus] had an older car, and unfortunately his stereo’s cassette player just wasn’t doing it for him. He always wanted to simply get into his car, pull out his cell phone, and have his music ready to play without any fuss. After messing around with all sorts of different tape adapters, he got fed up and decided to rig up an A2DP (Stereo Bluetooth Audio) adapter on his own.

He pulled the head unit out and started looking around to see how he could wire an adapter in. He figured the best course of action would be to remove the tape deck, and fool the stereo into thinking that a tape had been inserted. After spending some time tracing wires and studying how his old tape adapters worked, [Roofus] had an A2DP connection wired in and was ready to rock out.

Greeted with nothing but silence, he turned to his favorite hacking site (Hackaday, naturally) for assistance. Some friendly forum-goers helped him identify a ground loop issue, and he set off to his nearest RadioShack for a pair of isolation transformers that would fix his problem.

Once he knocked out the ground loop issues, his adapter worked like a charm. He put everything back together, and aside from a tiny switch he installed to toggle between audio sources, you would never know it was there.

Build Your Own SMS Chatroom

While he was organizing a party, [Mike Seese] hit upon the idea of chatroom that would operate over SMS. Not being content with the ‘reply all’ function, [Mike] built a Group Messaging Service that runs on his home server.

The chat room is initiated by sending a text to a server. Your friends then reply, and the chatroom is then opened. The project was written in C++, and [Mike] put everything on github for your perusal. The software does use libraries from /n software’s IP*Works, but if you have any trouble obtaining those libraries feel free to drop [Mike] a line.

The great thing about this project is the fact that it’s platform independent – as long as a phone can do SMS, it’ll work. Seems like a great thing for those of us still using the old Nokia ‘bar’ phones. An SMS chatroom has been done before but this is the first time we’ve seen a build that will run off your server, and not internet-based services.

While it may not be the best idea for people without unlimited texts on their phone plan, it’s a really great idea and we’re wondering why something like this isn’t available via Google Voice.

Hacking QR Codes For Fun And Profit

QR codes are everywhere these days, from being printed onto receipts to chiseled into granite tombstones. [Will] came up with a way to modify existing QR codes, and his hack has the potential to cause quite a bit of harmless mischief.

[Will]’s hack involves a little photo editing, transparency film, and some white-out/Liquid Paper/Tippex. After the ‘target’ and ‘destination’ QR codes have been imported into Gimp, the differences are found and the result printed out on a transparency sheet. After that,  hang the transparency over the original and the QR code now goes to the URL of your choice.

Continue reading “Hacking QR Codes For Fun And Profit”