Video detection

Kryten

New Member

• Oct 29, 2007

• #1

Hi
I need a circiut or an ide to help me with a build.
Im going to amplify composite video and are looking for a way to detect if there is input to my box.

Does anybody have any ide how to do this.

I was thinkin about usin a standard transistor as a switch to the amplifier but i dont know if i get enough voltage out of the camera to make it trigger.

 

Nigel Goodwin

Super Moderator

Most Helpful Member

• Oct 29, 2007

• #2

Use a 'missing pulse' detector, fed from a sync seperator - check for either the line or frame sync pulses.

 

ronsimpson

Well-Known Member

Most Helpful Member

• Oct 29, 2007

• #3

Use LM1881, EL1881, or EL4581 to get from “video” to TTL levels. (0 to 5Volts) As Nigel pointed out look for signals/no-signals on the H. Sync pin.
OR
The EL4583 Has a “no video” output.

 

Kryten

New Member

• Oct 29, 2007

• #4

Ok i should have said that i am going to use this in a cabin where there are only 12v solar power so low current is essential.

My plans are to use the detector insted of power switch.
Is that possible?

 

Nigel Goodwin

Super Moderator

Most Helpful Member

• Oct 29, 2007

• #5

I don't see the reasoning behind it?, if you're switching the source off, then just switch the monitor (or whatever) off as well.

 

Kryten

New Member

• Oct 29, 2007

• #6

Ahh I see I forgot to say that its for a amplifier. Need to get the signal 30 - 40 Meters away from the scource

(sorry for my bad english, Im norwegian)

 

Nigel Goodwin

Super Moderator

Most Helpful Member

• Oct 29, 2007

• #7

Kryten said:

Ahh I see I forgot to say that its for a amplifier. Need to get the signal 30 - 40 Meters away from the scource

(sorry for my bad english, Im norwegian)

Click to expand...

Then just switch the amplifier off along with the camera?.

 

Kryten

New Member

• Oct 29, 2007

• #8

hmm havent thought of that. Might be why im just a student still

Nice idea

 

Kryten

New Member

• Nov 19, 2007

• #9

Well ive just foundout where the amplifier are going to be placed. Under the cabin itself and it will have two scources to switch between, both going on the same line out from the amp.

Im going to use TI's OPA2690 (soic 14 pin with disable) so im looking for a easy way to detect either input a or b.