In this instuctable, I will show you how to make a cheap analog tv transmitter for channels 3-4.
Disclaimer: I am not responsible for ANY damage or an laws broken. REMEMBER, talk to local officials about any transmissions you plan to make because in some states, THIS IS ILEGAL, so be warned.
Anyway, if you succesfully complete theses easy steps, you could get a transmission radius of 5 miles easy. There is one problem, you need to have some knowledge about antenna lengths and tuning them. Other than that you are good to go! ;)
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Step 1: Materials:
This is what you need:
1. one RCA to TV RF Modulator- you can get it at any superstore like wal-mart or at Radio Shack (even at most Doller Generals)
B. Most mid-90's vcr players of a tv rf module, but you have to unsolder it after ripping apert the case.
2. RF TV cable with type-F connecters.
3. One power strip- can get it anywhere cheap.
4. Any vhf tv signal amplifiers you can get your hands on. For short range transmission, I recomend at least two amps.
5. You need one aditional tv amp but this one absolutely needs a Gain control. It is Essential you get one of these because your tv transmitter will not work. Radio Shack does carry these but they can get pricey. Try wal-mart first, or online.
6. You need an 75ohm to 300ohm converter with a copper wire attached as an antenna.
7. Finally, you need a video source-in this case it is a jazz digital camcorder- and a means of connecting your video source into the rca modulator.
Now that you have collected all of these components, it is time to assemble your transmitter.
Step 2: Assemble...
Now that every component is gathered, You first take the TV modulator and plug it in into your video source. Then you plug all of your amps and the modulator into your power strip.
Next, you take one of your tv rf cables you plug one end into the rf socket that says "tv out". The other end of that cable connects into the "in" socket of the amp with the variable gain. After that, you daisy chain all of the other amps onto the first amp with gain control. At the last amp attatch your antenna, just make sure it i tuned. That's it!!
Here is a picture of the one I made, it should give you an idea of how to rig this up...
Step 3: The Show
To Operate the Transmitter, you video source into the modulator. Some modulators turn on when it senses a video signal but others have a switch. Anyway, after that you choose either channel 3 or 4, attatch your antenna, then turn your tv on two channel 3 or 4 and ajust your gain control to view your video over the airwaves.
Here is the transmitter in operation.!!!