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Hello world, today I am bringing you another instructable at the request of another member.

I recently made an instructable about booting the Raspberry Pi from a usb flash drive (Boot the Raspberry Pi from USB). In that instructable I had my RCA connection "jerry-rigged" to work fast to display on a small CRT television to test that my method actually worked. Member Mason Wright asked if I could post a tutorial on how I connected the monitor using RCA with the Raspberry Pi 2, along with a few others who had questions regarding the deal with the alligator clips on the Raspberry Pi. I figured I'm on summer vacation, so why not give the people what they want?

What you need is:

1x - Raspberry Pi 2 (or I think maybe B+)

2x - Alligator clips

1x - RCA cable

1x - Monitor to connect to

Step 1: Raspberry Pi 2 TRRS Connection

Here I just give some info about the connection on the Raspberry Pi 2, feel free to skip this step if you don't care.

The audio jack on the Raspberry Pi 2 is one called a TRRS jack, which stands for Tip Ring Ring Sleeve. What this means is that it had four connections instead of the standard three that is common with normal audio applications. The TRRS jack is used on smartphones to provide audio as well as a microphone input, but on the Raspberry Pi 2, it provides audio as well as composite video.

By the diagram above, the farthest two connections are for audio, the closest is for video and the one in between is ground. The position of the video being closest to the jack housing, or farthest out in the female jack is critical for this method.

Step 2: The Raspberry Pi's Jack

If you take a look at the TRRS jack of the Raspberry Pi 2, you'll see that you can see a little metal prong which is very close to the opening of the jack. This little prong is the video output pin. It is close to the outside since on the previous diagram, the video pin on the male jack was also in the same place.

This makes wiring it up very easy since all you have to do is connect an alligator clip to that little pin. It's very close to the opening so it doesn't even have to go in very far.

But word of caution, if you do put it too far in, then you won't get any video since it might short with ground or an audio pin. Shorting with ground should not damage the Raspberry Pi since a standard TRS (yes, only one R this time) will short the video and ground, so safety measures have been implemented to prevent damage. BUT!!! In the rare event that your Raspberry Pi does get damaged by shorting video with something else, it is IN NO WAY MY FAULT since I am not forcing you to do this (and I see no reason why anything would get damaged).

Step 3: Connecting the Pi

Here you can see a picture of my Raspberry Pi 2 with an alligator clip in the audio jack.

Here is also where I got a few questions. Some people were asking why I had a black alligator clip connected to the HDMI casing, and they speculated that it was for static discharge purposes or something. It is actually used as a ground connection for the video signal since composite video uses one signal wire and one ground wire. You can use anything that is grounded on the Pi (HDMI casing, ethernet casing, USB casing, gpio ground, circuit board ground, etc) as long as it is connected to ground. I just chose HDMI since connecting to that case would make the black alligator clip face the same direction as the white one (I like symmetry :p ).

In the second picture, you can see the white alligator clip connected to the signal pin of an RCA connector and the black clip connected to the grounding part of the RCA connector. The other end of the RCA cable went into this little portable CRT tv I have that can also accept composite video input.

Step 4: Alternate Method

For those who are eccentric or need their Pi for a super compact, flat embedded project, I have just the thing.

If you need/want to solder your video connection, I have provided a picture of the underside of the Raspberry Pi 2 and have circled the video pin in red. If you solder one wire to any grounding point, and another to the video pin circled in red, then you can get video out in a very compact way.

I originally did something similar where I used an alligator clip on the HDMI casing and one clip to the little tab barely sticking through the solder to get my video. This was before I figured out I could do it straight through the TRRS jack.

Do you know if this works on the 3 still?
<p>It's the way it's wired on a Raspberry.</p><p><a href="http://www.raspberrypi-spy.co.uk/2014/07/raspberry-pi-model-b-3-5mm-audiovideo-jack/" rel="nofollow">http://www.raspberrypi-spy.co.uk/2014/07/raspberry...</a></p><p>I've no idea why this instructable exists. Using a TRRS plug is easiest for analog audio and analog video.</p>
<p>This instructable exists because not all of us have a TRRS to RCA adapter.</p><p>There are cases in which it makes more sense to cobble one together and use it now than order one and wait 2 weeks to get it.</p>
<p>Can I use it for audio input?</p>
<p>There is no audio INPUT on a Raspberry without using a USB sound card or an add on Audio DAC HAT (or pHAT).</p>
<p>I don't think so, the hardware connected to those pins is for outputting audio and video, not inputting.</p><p>Now, if you have mad hacking skills, then you could probably find some way to add audio input besides connecting a USB soundcard to it ;)</p>
<p>what is 3 rd wire</p>
<p>If you're talking about step 1, it's the ground pin, kind of like the baseline voltage pin.</p><p>If you're talking about step 2, it's the micro USB plug to supply power to the Pi.</p>
<p>Your TRRS diagram is wrong. It's left audio on the tip, right audio on the first ring.</p>
<p>Is this exclusive to the Raspberry Pi, or is it in general?</p>
<p>thank you I need help</p>
<p>Great instruction, especially the soldering on the back is helpful to get to the video signal.</p><p>Thanks</p>
<p>if i desolder the TRSS jack, i can use one of its two mounting through-holes as my video ground, right?</p><p>since the TRRS &quot;case&quot; is grounded?</p>
<p>Should work, but anyways, try it and let us know :)</p>
it did, thanks!
thanks
<p>I actually tried this and it worked. One question though, how were you able to force the rpi2 to use the composite video? I have an old portable dvd player with video in jack. I was able to get a display during set-up (you know the hold the &quot;shift key&quot; &amp; press &quot;1,2,3,4&quot;) but everytime the rpi2 rebooted it reverts back to using hdmi. I followed instructions from this site. (https://bhavyanshu.me/tutorials/force-raspberry-pi-output-to-composite-video-instead-of-hdmi/03/03/2014/). hope you can help me with this. thanks!</p>
<p>never mind the comment above, I just saw that I was using a UK keyboard layout when I was editing the config.txt. This together with the barely legible characters on the screen meant I was not typing the commands correctly. Cheers to this awesome RCA connection! :)</p>
I found an old 4 mini plug but ground and video are swapped.
Thank you this really helps :)
it may be different on the pi 2, but with my pi a+ I you can actually scratch out the trace on solder on a wire so that if you plug in a TRS, you still have video output. I will publish an instructable soon on my pi project and it will have more details.
<p>Thank you very much for this 'ible. :)</p>
very cool

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Bio: I am a total nerd who works as a software developer, and knows a bit about computer/software technology. Plus I like space and vintage ...
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