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Urgent help! Can a second video source be added using 2 in 1 RCA splitter cable?

ZOGAM

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Hello, TV has only 1 input RCA port which means only one video source is available/activated at one time say CCTV1.

Now, I want to add second video source say CCTV2 to the same input RCA port using 2 input RCA to 1 output RCA splitter cable as shown in attached photos. I add a switch to the power supply side of the second CCTV2 so that I will be able to switch between the 2 CCTVs with only one camera activated at a time. CCTVs has 4 wires - power, ground, video signal and video ground.

The inner rings of the input 2 RCAs are internally connected marked as "BLUE COLOR" and through to the inner ring of the output RCA port.

And, the outer ring of the input 2 RCAs marked as "BLACK COLOR" are also connected together with the corresponding outer ring of the output RCA port. Hence, are grounded.

Now, that when the CCTV1 is ON, the video signal flows from pin 2 (BLUE COLOR) of the splitter RCA, and all the way to the inner ring of the output RCA, hence, displaying images/videos on the TV properly. But, at the same time, since the inner rings of the input RCAs are internally connected, the same video signal is also available at the pin 3 of the lower RCA port.

In this scenario, I have the following questions:-
1. Will this reverse signal voltage flows back into pin 3 of the lower RCA although the CCTV2 is not power ON i.E. Switch is OPEN?

2. Will this signal voltage of the CCTV1 have any affect/damages on the CCTV2 although the CCTV2 is power OFF i.E. Switch is OPEN?

3. Will there be signal distortion at the TV due to this signal voltage at pin 3?

4. Same confusion for CCTV1 when CCTV2 is ON.

5. If any affect arises due to this video signal voltage, how do I rectify this so that I can use any of the 2 CCTVs at one time using the same 2 in 1 RCA splitter cable? Will diode or capacitor etc works to BLOCK this signal voltage so that the signal voltage does not reach pin 3 when CCTV1 is ON, and does not reach pin 2 when CCTV2 is ON?
 
It MIGHT work but I wouldn't recommend it. The reason is as you thought, you are joining together two video outputs and the circuitry behind them will always be connected, regardless of whether the power is on or not. Most likely you will find the device turned off will load the active one and reduce or even distort the video level.

Your simplest solution is to use a change-over relay instead of the 2-1 splitter. If you power the relay from the 12V it will work as an electrically operated switch. Connect the common contact of the relay as the video output and one of the normally open or closed contacts to each of the sources.

Forget the diode/capacitor idea - it will not work.

Brian.
 
Connect the common contact of the relay as the video output and one of the normally open or closed contacts to each of the sources.

Brian.
But will not the magnetic field induced by the relay coil distorted or reduced the video signal flowing out to the TV unit???
 
No, it will not have any effect on the video. The magnetic field inside a relay is almost entirely confined to the core of the coil and is quite small anyway. The video goes through the switch contacts, the magnetic field is only there to pull the switch mechanism into place.

Brian.
 

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