This is a hat with integrated Tv-B-Gone and a couple added features such as rapid fire mode which will turn off (and on) the most common tvs more frequently and constant on mode which will repeat the off codes for all tvs indefinately.

Questions or comments? jacob@makezine.com

Step 1: Gather the Materials

MATERIALS
1 TV-B-Gone
1 Hat
1 555 Timer IC
1 5V Relay
3 IR LED's
2 Micro-Switches
1 0.1uF Capacitor
1 220uF Capacitor
1 10K Resistor
1 100K Potentiometer

TOOLS
Soldering Iron
Wire Cutters/Strippers
Plyers
Sewing Stuff

Step 2: Build the Timer Circuit

We will be configuring the timer in astable mode the relavant schematic is on page 9 of the NE555 datasheet from Texas Instruments, available at: http://www.ortodoxism.ro/datasheets/texasinstruments/ne555.pdf
Ra = 100K pot
Rb = 10K res
C = 220uF cap

Note that pin 4 may be left unconnected and I have replaced the 0.01uF capacitor in the schematic with a 0.1uF, either will work.

The first thing to do is clip off the leads we wont be using, in this case pins 4 and 5 should be removed. Next bend pin 2 under the bottom of the timer, this will be connected to pin 6. Flatten the remaining leads using a small pair of plyers.

Now that the IC is prepared the components can be added. It is important to keep the layout as flat as possible since this will be mounted on the bill of the hat.

Once all the components are added solder wires for gnd to pin 1, power to pin 8 and the timer output to pin 3.

Step 3: Attach the Relay

If your relay did not come with a datasheet or any useful information you will probably have to figure out which pin is which on your own. To do this use a multimeter checking between all possible combinations of pins to find a pair which have a resistance of a couple K ohms. This is the coil. Connect the coil to a 5v supply and check for continuity on other pin combinations, when you find a combination that is continuous, remove power from the relay. If the two pins are still continuous keep looking (also try reversing the polarity of the 5v supply). If the connection breaks then these are the NO (Normally Open) pins, the pins we want.

Connect the output of the 555 to the + side of the coil and connect the coil gnd to pin 1 of the 555. Next add wires to the two pins you just itdentified as the NO contacts.

Step 4: Modify the Tv-B-Gone

Open up the case and remove the circuit board. The circuitry of the Tv-B-Gone is pretty simple so our modifications are relatively mundane. Remove the IR LED and replace it with wires. Next solder wires to opposing sides of the push button switch. At this point we chose to spray paint our board black. Flip the board over and make connections to +6v and gnd.

Step 5: Attach the Circuitry to the Hat

You can really put this wherever you want but the underside of the bill seemed like the most appealing place. Sewing through the bill of a hat sucks but it works, attach the ground from the 555 to the Tv-B-Gone ground and connect the outputs from the relay to opposite sides of the push switch. Next run the wire from pin 8 of the 555 (+) and the 6v supply from the Tv-B-Gone to one slide switch and the remaining two leads from the push button switch to the second slide switch. Finally connect the three IR LED's in series to the LED output on the Tv-B-Gone. Thats it. Done.

Step 6: Use It

The slide switch that is connected directly to the push button switch puts the Tv-B-Gone into repeat mode where it repeats the 60 second cycle indefinately. The slide switch connected to the 555 timer puts the hat into rapid fire mode where it will repeat the first X seconds of tv off codes (these are the more common codes that are placed first). To adjust the number of seconds before the cycle repeats adjust the 100K potentiometer, a good value is about 70K. Note that if the repeat switch is on the rapid fire switch will have no effect.

To test out your creation use a cell phone with a camera, put the cell phone into picture taking mode and point it at an IR LED then hit the push button on the Tv-B-Gone. You should be able to observe the LED blinking on the screen of the cell phone.

Once your sure it works you should spend some time aiming the LEDs properly so that they turn off tvs you are looking at and they dont get shielded by the bill of the hat.