Video Transmitter Sender Circuit # 3

Video Transmitter Sender Circuit # 3 VHF ½ Watt

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Microphone Preamplifier Circuit using a TL071 Chip
This is a very powerful video transmitter, sender circuit that transmits its signal for quite a distance. L1 and L2 are 3 to 4 turns of #24 copper wire about ¼” diameter. The Video Adjust 2K trimmer is the video balance. The input video signal is provided by an external camera, CCD black and white or color.
The 2N4427 - Power Amplifier requires a heat sink. The 2N4427 is capable of delivering 1 Watt of RF at VHF frequencies so be sure that either a 50-75 Ohm dummy load or antenna is connected at all times before applying power when testing. Never turn the unit on without a dummy load or an antenna attached. Use a small piece of flex wire about 18" for an antenna.
Any composite output device to feed the transmitter will work. Cameras, game consoles, etc.  Tune the transmitter to an unused channel. For reception use a small portable and tunable battery operated TV set of the type you find in thrift stores or at a flea market.
Since there are three trimmer capacitors, you should use some form of field strength meter that will indicate power. Tune all three trimmers until a maximum signal is obtained. When at that point, tune your TV receiver to the upper channels and slightly adjust the two 30pf capacitors until you see your video signal.