Video switching ( 14 ) :

• MOSFETs reduce crosstalk effects on analog switches - Some cost-effective analog multiplexer/demultiplexer ICs, such as the CD4053 and CD4066, find frequent use as signal distributors. These digitally controlled analog switches have low on-resistance. However, with all channels in the same package, crosstalk can be annoying and unavoidable. The circuit presented in this article provides a cost-effective and viable method of solving this problem.   
• 48-input�16-output crosspoint IC eliminates the need for multiplexer amps - multiple camera inputs while providing playback and multiple loop-through to multiple monitors. To provide video loop-through or monitor outputs, these systems often require additional multiplexer amplifiers that can drive standard video loads. Thus, one or more external multiplexer amps often follow a crosspoint-matrix switch. As an alternative, you can employ a 32�16 nonblocking crosspoint-matrix switch, whose 16 2-to-1 multiplexers eliminate the need for extra multiplexer amps. The MAX4358 IC is a fully buffered, 32-input�16-output nonblocking crosspoint switch that includes 16 additional buffered analog-video inputs (OSDFILL) intended for the insertion of OSD (on-screen-display) information.   
• Build A Video Switcher - Automatically or manually switch the outputs from up to four cameras into one video monitor, pdf file
• Printer port controls video multiplexer - four-channel computer controlled video-signal multiplexer for video frequencies as high as 300 MHz   
• Remote Controlled AV Switch with S-Video, Composite Video, and Audio
• S-Video Source Selector   
• Low-Cost, Two-Chip Voltage-Controlled Amplifier and Video Switch   
• S-Video Source Selector - Connecting a DVD player to the S-video input on a television produces an amazingly sharp picture. However, what if you have more than one device that generates S-video but only one input on your TV? Then you'll need this simple switch to select between the two sources. This is a simple mechnical switch design for S-video signals.   
• Video multiplexer uses high-speed op amps - This circuit shows a video multiplexer configuration using high-speed op amps in a video-multiplexing application.   
• Video Switch - This article (published in Circuit Cellar Magazine) describes a circuit which switches RGB signals between two genlocked cameras. This project used analogue switcheds and programmable logig (programmed using VHDL). This article is also available in   
• VISW 8 x 4 Stereo audio/video router - VISW module (mono) was designed years ago, primarly as main AV crossing switch for ATV repeaters. Years after, the Win95/98 VIPS package was written to enable simple use at home with help of PC as main controller.   
• Zoomkat's "El Cheapo" Parallel Port Video/Audio Switcher - Homemade web controlled parallel port video switcher made from Radio shack parts. ). This one is set up for 3 cam video/audios in and one out to capture card and audio card. The schematic shows for one parallel pin to switch a cam video/audio on/off using 2 resistors and 2 transistors. The combined output of 3 of these are connected at the video out and audio out RCA connectors for single seperate outputs to the video and audio cards.   
• Zoomkat's "El Cheapo #2" Parallel Port Video/Audio Switcher - This is version #2 of a homemade web controlled parallel port video switcher made from Radio shack parts. It can be used with other webcam programs, but you will need to make accomidations with a webserver CGI setup for web control. This switcher is set up for 4 cam video/audios in, and one video/audio out to capture card and audio card.   
• Zoomkat's "El Cheapo #3" Parallel Port Video/Audio Switcher - This is version #3 of a homemade web controlled parallel port video switcher made from Radio shack parts, using the 74HCT259 8-Bit Addressable latch switch. . It can be used with other webcam programs, but you will need to make accomidations with a webserver CGI setup for web control. This type switcher should work for up to 40 cams (using 5 chips) video/audios in, and one video/audio out to capture card and audio card. The schematic shows the wiring for four parallel port pins to switch 8 cams video/audio on/off using 2 resistors and 2 transistors per cam.   

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