Introduction: Double the Range of Your TV-B-Gone
With a handful of parts, a solder iron, and about an hour, you can double the range of your TV-B-Gone (R) universal remote control.
TV-B-Gone remotes work great to turn off TVs anywhere you go. But they work even better when they have more power.
We will be adding one more IR emitter to a TV-B-Gone remote, and powering the resultant two IR emitters with larger batteries than the small coin cell battery in the stock TV-B-Gone.
(There is also a more complex yet Ultra High Powered TV-B-Gone Instructable.)
This Instructable grew out of workshop that I did at 23C3, the hackers conference in Berlin in December, 2007. FoeBud, a German organization that educates the public about privacy issues with technology, let me use their workshop bench to teach people how to solder, using this project as an example.
Thanks to Rena Tangens, of FoeBud, who took all the photos.
Step 1: Materials and Tools
A -- TV-B-Gone (1)
B -- 940nm IR emitter (1)
C -- Battery Holders that holds two batteries (2)
D -- Batteries (4)
E -- Solder
F -- Solder iron
G -- Small Phillips screwdriver
H -- Needle nose pliers
I -- Diagonal cutters
-- Wire, several inches of two different colors
-- Wire stripper
-- Solder Wick (or a Solder Sucker)
This photo has Notes -- roll the mouse over the parts with squares to see these important notes.
Step 2: Take Apart TV-B-Gone
Unscrew the small Phillips screw on the back of the TV-B-Gone. (See 1st photo.)
Take off the back. (See 2nd photo.)
Take the PCB out of the plastic housing. (See 3rd photo.) (PCB stands for Printed Circuit Board -- it is the board that all of the components are soldered to.) Your modified TV-B-Gone will not fit into the cute batman-like keychain after you are finished, so please recycle or re-use the plastic and metal pieces for some other project.
Take the battery out of the battery holder marked B2. (See 4th photo.) Save this battery, as we will need again later.
Take the battery (or batteries) out of the battery holder marked B1. (See 5th photo.) This battery (or batteries) will not be needed for the modified TV-B-Gone, so please re-use or recycle.
Step 3: Prepare Battery Holders
Cut 1 1/2" of wire (I used red) and strip 1/8" off of each end. Solder it between the positive terminal of one battery holder and the negative terminal of the other. (The negative terminals of the battery holders are the ones that look like springs.) (See 1st photo.)
Cut 4" of one colored wire and 4" of the other colored wire. Strip 1/8" off of each end of each wire. Solder one wire (I used Red) to the unused positive terminal of the battery holder and the other wire (I used Blue) to the unused negative terminal of the battery holder. (See 2nd photo.)
The result is that when the batteries are installed in the battery holders, there will be 4 batteries in series, making 6 volts to power the IR emitters.
Step 4: Prepare Original IR Emitter
Unsolder the IR emitter from the PCB. To do this, hold onto the plastic part of the IR emitter with your fingers of one hand and pull gently, while using you other hand to melt the solder pads on the PCB with a solder iron. You will need to go back and forth, first melting one pad and pulling gently, then melting the other pad and pulling gently, then back to the first, etc., until the emitter comes out. (See 1st photo.)
Use Solder Wick (or a Solder Sucker) to open up the two holes on the PCB for the emitter. You should be able to see through the two holes. (See 2nd photo.)
Bend up the negative lead of the IR emitter as shown in the photo. (See 3rd photo.)
Solder the positive lead of the IR emitter (the one you did not bend up) into the pad marked "+" as shown in the photo. Now the IR emitter is in the same position it was in originally, but with the negative lead bent up. (See 4th and 5th photos.)
Step 5: Install 2nd IR Emitter
IR emitters come with one lead longer than the other. The longer lead is the positive lead and the shorter lead is negative. (See the first photo.)
Bend up the negative lead (the shorter lead) of the IR emitter as shown in the 2nd photo. There should be about 1/8" of lead sticking out from the emitter before the bend (as you can see in the 2nd photo).
Push the negative lead (the one you just bent) into the empty emitter pad on the PCB and solder it. Be sure to solder it on the opposite side of the PCB from the original IR emitter. (See the 3rd photo.)
Clip the excess lead that sticks up through the PCB. (See the 4th photo.)
Bend the positive lead of the new emitter around as shown in the 5th photo.
Continue bending the positive lead of the new emitter around the bent up lead of the original emitter as shown in the 6th photo.
Solder this connection between the positive lead of the new IR emitter and the negative lead of the original IR emitter. Then cut the excess lead. (See the 7th photo.)
Step 6: Attach Batteries
Solder the negative wire (I used blue) from the battery holders to the pad on the PCB shown in the 1st photo.
Solder the positive wire (I used red) from the battery holders to the pad on the PCB shown in the 2nd photo.
Insert the 4 batteries into the battery holders, making sure the negative of each battery is at the spring in the battery holders, as in the 3rd photo.
Insert the CR2032 coin cell in battery holder B2 on the PCB, with the side marked "+" facing out. (See 4th photo.) Do not insert any coin cell batteries into battery holder B1 on the PCB.
As soon as you insert the coin cell into B2, the visible LED on the PCB will blink (see 5th photo) -- 6 times for European database, or 3 times for North American database (see Step 9 for changing between North American and European databases). If it does not blink, then there is probably something wrong with the voltage from the new battery holders you added (see the next step, Step 7, for testing & debugging tips).
See the 6th and 7th photos for two views of the finished high-power TV-B-Gone.
You can use your High Powered TV-B-Gone as it is, or you can put it in a new case (it won't fit in the original, cute batman-like case any more). Some people have used a cigarette box.
Step 7: Testing and Debugging Tips
The IR emitters emit very bright light! But the light they emit is invisible to our eyes (IR stands for Infra Red, which means that its frequency is below visible red light). IR remote receivers in TVs can "see" IR, and so can digital cameras.
To test your new high-powered TV-B-Gone you can point it at a TV, push the button on the TV-B-Gone, and keep it pointing at the TV until the TV turns on or off. To test it more thoroughly, push the button on the TV-B-Gone and point it at a digital camera -- if your high-powered TV-B-Gone is working you will see the three blinking lights on the camera: the visible LED, and both IR emitters (even though you will not see the IR emitters blinking with your eye).
If the visible LED didn't blink when you inserted the coin cell into B2, or if both IR emitters do not blink when viewed with a camera (and you can't turn a TV on or off) then you will need to debug the circuit. There are only two areas that can go wrong: the voltage from the new battery packs, or the orientation of the new emitter.
If you have a volt meter, measure the voltage where the wires from the battery holders are soldered to the PCB -- is there 6 volts, with the correct polarity? One of the battery packs I bought at Conrad in Berlin was defective (they are made pretty cheaply), so I had to replace it.
If the voltage is OK, the only other problem could be with the IR emitter -- maybe it is a freaky one with the polarity reversed (one that I bought at Conrad in Berlin had the negative lead longer than the positive lead, unlike any LED I had ever encountered before). If so, then remove the new emitter, reverse it, and test again.
Step 8: Use It!
Go out into the world and enjoy the satisfaction of making it a better place by turning off TVs everywhere you go.
Step 9: North American Vs European TV-B-Gone
Since there are so many different makes and models of TVs around the world, with hundreds of different POWER codes, TV-B-Gone has a different database for Europe (EU) and for North America (NA). The NA model also works well in Asia. TV-B-Gone determines whether to use its EU or NA database by looking at the jumper in R5 (see the red circle in the photo -- the photo shows an EU TV-B-Gone). R5 can be anywhere from 0 ohms through 15Kohms. If the jumper across R5 is present then the TV-B-Gone uses its EU database. If the jumper is absent it uses its NA database. You can change your TV-B-Gone from one to the other by removing or adding the jumper (but please remove all of the batteries while soldering). Some people have installed a small switch to make it easier to change between databases.
Step 10: Schematic Diagram
Although you don't need it to follow the previous steps, here is a schematic diagram for those who want one.