| Author | Views | Views Today | Rank | Comments |
| 16,148 | 4 |  |
6 |
| Author | Views | Views Today | Rank | Comments |
| 16,148 | 4 | |
6 |
| This simple circuit from the May 1996 Think Tank column of Popular Electronics activates a relay when it senses a composite video signal. This allows you to use the tuner built into your VCR to turn on and off older TVs that are not equipped with a remote. It can also be used to activate surround sound equipment, turn off the room lights, turn on video game consoles, etc. For such a simple circuit, it is very versatile. |
Schematic |
Parts |
|
Notes |
Related Circuits |
Comments |
| Simple, efficace, permet de multiples utilisations, par exemple dans la video HF... Merci pour ce petit montage. | ||
| what is the function of the video activated relay? | ||
| hello,plz i need circuit for my project can you kindly give me comphrensive note about it. | ||
| works great... but you have to use a 2n2222 for Q1... if you use a 2n3904 then you have to replace R1 with a smaller value(51 ohms worked... but it made the video going to the tv get slightly white-washed)... using the 2n2222 saturated the transistor and didnt make the video any different... | ||
| I think the D1 will cause a LOAD on the video signal, and maybe also R1 since it is only 10K. | ||
| This seems like a very good circuit. The only thing I see wrong is that it operates on 9V instead of 12V. Since most of the applications will normally be with a 12V video camera. | ||
| The last 10 comments are currently shown. Show All Comments. |
If you would like to leave a comment, you can do so using the form below. Comments can be things like suggestions, successes or failures, improvements, similar circuits, error reports, an answer to a previous commenter's question, or anything in between. However if you would like to ask a question it is suggested that you use the forum instead. The forum provides a more robust environment for discussion.
Important: If you post a technical question here, there is no guarantee it will be answered. All technical questions should be posted to the forum. The owner of this site generally does not answer questions in comments.
All comments are subject to approval before they are displayed here, so your comment will not appear immediately. This is done mainly to prevent spam and other abuse. If you wish to remain anonymous, simply enter "anonymous" for your name and/or email.