In this review we examine an easy to build kit from adafruit industries that offers literally hours and hours of fun, if you like to get up to some mischief – the TV-B-Gone. This fascinating little device is basically an infra-red remote control for televisions and some monitors. It has a microcontroller programmed with the “off” code for a wide range of display brands, and four very strong infra-red transmitting LEDs, two with a wide beam, and two with a narrow but longer beam.
Here is the little culprit in standard assembled form:
It is a very easy kit to assemble, once again the team at adafruit have published an extensive amount of information, from assembly tutorials to how it works, and even the design itself as the kit is open-source hardware. So in this article you can follow the assembly, and use of this bag of fun.
As usual, this kit arrives in a resealable, anti-static bag. After ensuring I had the correct parts, from the documentation on the adafruit website, it was time to follow the simple instructions and start getting it together. Now this will be the second time I have built a TV-B-Gone… the first one is in the photo above, and had me removed from a department store (thanks Myer…) – so this time I am rebuilding it to fit inside a typical baseball cap.
Soldering it was quite simple, the PCB is solder-masked and has a very well detailed silk-screen:
Just following the instructions, and being careful not to rush is the key. Another feature of adafruit kits is that the are designed very well with regards to troubleshooting. For example, you have the opportunity to test it before finishing. So at this stage you can fit the AA cells and power it up, if the LED blinks you’re all good:
And we’re done… almost.
For installation into the hat, the button and the LEDs will need to be a distance away from the PCB. At this stage I was not sure where to put the button, so for now it can stay on the side of the cap:
Naturally you can use any momentary push button, however I will use the included example (above) with a length of wire. With this style of hat, especially a black one, slight bulges underneath the surface do not seem that apparent, however it is wiser to spread out the entire unit:
Although thinner AAA cells could be used for the power supply, for a good day’s action you will want the extra capacity of AA cells, so we’ll stick with them for now. The next step was to wire up the LEDs. They were connected individually to the PCB with lengths of wire, and heatshrink was used to insulate and darken the legs:
And finally the finished product, ready for insertion into a piece of clothing, or in our case – a cap:
At this point it was time to take it for a test toast. The quickest way to test an infra-red transmitter is to look at the LEDs through a digital camera – it can display the infra-red wavelengths whereas the human eye cannot see them. For example:
Those LEDs can get very bright (in infra-red terms), and is also how night-illumination for digital security cameras work. If you had a lot of those LEDs pointing at a security camera at night, you could blind it. That gives me an idea…
Assembling the kit in this format gives you lots of options for hiding it. For example, you could:
- put the PCB and power in a jacket’s inside pocket, and have the LEDs poke out the neck;
- place them in a cap as we are;
- use a large ladies’ handbag, with the LEDs out the top, and the button underneath a handle;
- sew the LEDs into the head-cover of a hooded jacket (with some longer leads) and have the PCB, power and button in the pockets
So here are the LEDs mounted under the brim of the cap:
If you are going to staple them in, be careful not to puncture the wires. The ends of the staple should come through to the top of the brim – in this case I covered them with black ink from a felt pen so they would blend in. The button lead’s position is down to personal preference, in my case the button is just poking out next to the strap on the back of the cap. So all I need to do is appear to scratch the back of my head to activate the TV-B-Gone.
And here is the finished product, with an unfinished author:
Well by now you want to see it working. So here you are… I went on a field trip wandering about the central business district of Brisbane, Australia:
My apologies for the shaky footage, doing this isn’t something you can really capture with a camera and a tripod. 🙂 The problem was getting close enough, or most places had either covered their IR receiver, had a brand of TV not recognised by the TV-B-Gone, or used a large monitor instead of a television. But it was fun nevertheless.
In conclusion, this is an easy to assemble kit which is fun and certainly will get you into harmless trouble. Again, this is the type of kit that would be good for those who are being introduced to the fascinating world of electronics (etc) as it is quick to build, and does something with the “real world” that young people love so much. Or anyone else for that matter.
As much fun as it is to switch off televisions and advertising monitors, I would hope that end users will still be responsible with their TV-B-Gone use. Please head into a department store, your favourite eatery, coffee shop or mall and switch off the TVs. However, please do not turn off displays in railway stations, airports or other places where the authorities will take offence. You will get in real trouble. Or if you’re feeling suicidal, go switch off the TVs at the OTB.