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How to Build A Television Transmitter

Do you think that Building A Television Transmitter is not possible? For some time now it has been possible to construct a clandestine television station, which you can operate from your Telecommando Lair, or modify for Mobile Media Guerrilla campaigns.

We have named this device the Snow Box, due to its cool nature, and the snow seen on blank television channels waiting to be commandeered.

To put together a TV station you will need this stuff:

A VCR or Camcorder with video or RF outputs

A Ham Radio 6-meter Band Linear amplifier (This boosts the RF signal from the VCR for broadcasting) (The Linear Amp should have a bandwidth of 6 MHz for best results) A cable television RF distribution amplifier may also be used.

Coaxial cable with UHF connectors (Connects the Linear Amp to the Antenna)

A cable-TV patch cable with an F-connector and a UHF connector (To connect the RF signal to the Linear Amp) (F-connectors are the small ones used with cable TV) (UHF connectors are the large ones used for Ham Radio)

If your VCR does not have RF outputs: An external RF modulator (converts video to channel 3,6,12 etc.) a cable with RCA connectors (a standard stereo cord is ok)

A 6-meter Ham radio antenna.

If you do not have a pre-made 6-meter antenna:

About 20 feet of strong wire 3 ceramic antenna insulators another UHF connector

Likely places to get the linear amplifier, connectors and cables is a Ham Radio swapmeet, a Ham club newsletter’s classified ads, a Buy-Sell-Trade paper like The Recycler, or at a store specializing in Ham gear. RF modulators are available at specialty video stores, or major VCR dealers.

Setting Up the Transmitter:

Using a VCR with RF out:

how to build a television transmitter How to Build A Television Transmitter

Diagram Symbols:

U – UHF-connectors (Ham radio)
F – F-connectors (cable TV)
R – RCA connectors (stereos)
— coax, cables, wires
[] – devices (name of device in brackets)
<I> – ceramic insulator (the kind with a hole at each end)

Building The Dipole Antenna:

how to build a television transmitter2 How to Build A Television Transmitter

To Build A Television Transmitter, you should know that the antenna is set up much like a clothesline with the wires tethered straight out horizontally. The outer insulators are used to isolate the antenna from the tether lines, which should be rope or nylon cords for good results. The inner insulator isolates a gap between the two long wires of the antenna.

The length of the wires used for the antenna is critical. Look up the length in feet for the channel you want to use in the table below & make each of the two long wires that length. As a rule of thumb, a wire half-wave antenna’s length in feet is equal to 468 divided by the frequency in MHz.

how to build a television transmitter table How to Build A Television Transmitter

For Further information: Look in the ARRL Handbook published by the American Radio Relay League for detailed plans & theory for antennas, transmitters & linear amplifiers. The info in that book can be used for setting up an underground AM or FM radio station.

Uses for a TV Clandestine Station:

Public Education:

Make a videotape of each step in the process of constructing your transmitter. Show this tape in your broadcasts, “For informational purposes only”, of course.

Short-burst zipping:

From a fixed or mobile base of operation show short snippets of graffiti-like computer graphics, quick subliminal messages, images & suggestions, or brief phreaker manifestos. Commercials are an opportune time to break into TV broadcasts.

Live call-in shows:

Using a Cheese Box, or other device for receiving untraceable phone calls and a video camera do a live call-in show. Encourage people to call in using Red, Blue, and other phreaking boxes.

Cable TV Piracy:

With modifications it may be possible to feed the power RF signal directly into a cable TV system, overriding cablecasts or comandeering unused channels.

Mobile Operation:

Using storage batteries and a 110-volt inverter the transmitter may be modified for mobile use to avoid detection by the FCC during long broadcasts. Battery operated mobile linear amps and portable camcorders are also available.


Comments (1)

  • Professor, Paul West

    Most interesting concept indeed, building one’s own television transmitter. My only problem when using that VHF band is the unwanted creation of those troublesome spontaneous sidebands, with the root cause being that high video amplitude cross band interference. That can cause some real havoc, with police scanner frequencies and a few upper FM radio bands.

    Far better to use UHF starting with channel # 14 (471.250 MHZ) even a multiple sideband generation from this UHF channel can cause some weak interference on those highly sensitive cell phone frequencies. however,tests have shown, these higher frequencies to be far superior to the lower ones.

    You can easily build a single channel TV modulator using an old dis-guarded cable box that uses a PLL freq control chip. The frequency can be easily change by simply inserting a difference value crystal. Note: most cable boxes have UHF oscillators feeding the mixer converter stages. Once the transmit frequency has been established, that crisp clear video modulation is accomplished using a single high-frequency amplifier stage that his collector modulated.

    Thus,this single stage has its output alternated using a small signal diode clipped to ground. The RF output when modulated will be roughly .0035 of a Watt. Now although this sounds extremely weak it can be easily boosted to 2.5 watts using a high again UHF amplifier??? Such as the kind that are widely used in those older version mobile phones. The trick to using this type of amp is to never remove it completely from the cell phones circuitry, simply adapt it with a input/output port. Also note: the high freq module makes a perfect broadband amplifier However, your homemade UHF TV transmitter must operate on a frequency no lower than 777.250 MHZ channel # 65 OR 801.250 channel # 69.

    good luck!

  • sergio

    。◕‿◕。 Sua Smart TV est

  • Emerson Miranda

    Oi galera, gostaria de UMA Ajuda, eu adquirir hum Pacote de TV HD PC n

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