Video Operated Relay

Posted on Sep 16, 2012

Many Video Operated Relay (VOR) circuits have been published in recent years for use in connection with ATV repeater controllers or automatic videotape logging systems. Unfortunately, many of these circuits fail to properly detect certain video signals depending on their signal-to-noise ratio or their picture content. Most designs rely on using an LM567 phase locked loop (PLL) tone decoder chip to detect the presence of horizontal sync energy in a composite video signal, and this alone is probably the greatest cause of the poor performance provided by many of these circuits.

Video Operated Relay
Click here to download the full size of the above Circuit.

One of the worst approaches to video sync detection has been the design used by the Micro Computer Concepts VS-100 ATV Repeater Controller. This controller couples baseband video directly into an LM567 PLL tone decoder tuned to the video horizontal sync f

Leave Comment

characters left:

New Circuits



Popular Circuits

FM reciever with classic TDA7000
Photodiode signal conditioner
Simple FM transmitter
5V Supply High-Side Switcher
Easy Build Motorcycle Alarm
Door Knock Alarm Circuit
dimmer circuit puzzle
LM1036 volume controller equalizer electronic project
The Wien Bridge theremin
0 to 10V output multiplexer measuring circuit