No video using aux channel on t.v.

[skaldicpoet9]

Just got a Raspberry Pi but the video isn't showing up on the aux channel on my television. I have the yellow composite cable plugged into the front video input on the t.v. When I turn on the Pi the television only displays a black screen. In using a model b pi with the Raspbian Wheezy image.

[drgeoff]

Can you use another video source(*) to test the cable, the TV input circuitry, selection of the correct Aux input?

*eg a VCR, a DVD player, a games console, a camcorder, some digital stills cameras etc.

What OS are you booting and how did you obtain it - ready-made or flashed it yourself?

Does the green LED labelled 'Act' flash?

[skaldicpoet9]

Unfortunately the only input device I own currently is the Pi. However, I have tried plugging the Pi into another t.v. aux input with the same results. The next thing I was considering was visiting Free Geek and using one of their monitors.


The image is the Raspbian pre-made image that is on the official Pi downloads page. I just used the Win32 disc imaging utility to flash the SD card.

Yes, the green l.e.d blinks intermittently. As a side note, I have booted into Raspbian through vncserver on a laptop and installed dungeon crawl, so I know it does boot. (no longer have access to the laptop though)

[Burngate]

It sounds like the Pi is booting, but the TV isn't seeing it.
If there is no HDMI connection the Pi will default to the RCA composite output (unless told otherwise in config.txt)

If you unplug the cable from the TV, does anything change? Does the TV now complain about no signal? If so, then something's going down the cable.
Otherwise it could be that the TV isn't actually looking at the correct input. Any reason for that is down to the set manufacturer, and may have no logic behind it!

[mahjongg]

Maybe your TV isn't accepting the NTSC signals that a PI defaults to!
you can choose PAL by changing a line in the config.txt file on the card, you can use notepad under windows to do it.

see the wiki section on config.txt

[skaldicpoet9]

I don't know why that would be the case. The televisions are both NTSC sets. My only guess is that maybe the video cable I'm using is not outputting a signal. When I get the chance I'll buy a new one and see if that's the case.

[drgeoff]

I don't know why that would be the case. The televisions are both NTSC sets. My only guess is that maybe the video cable I'm using is not outputting a signal. When I get the chance I'll buy a new one and see if that's the case.

If you have an audio cable with RCA phono plugs at each end - typically one red and one white at each end - that will work well enough to test if the other cable is the problem.

[skaldicpoet9]

Yeah, I hooked up my girlfriend's android via RCA audio and her music outputted through aux perfectly. I am really starting to think it's the video cable at this point.

[drgeoff]

Yeah, I hooked up my girlfriend's android via RCA audio and her music outputted through aux perfectly. I am really starting to think it's the video cable at this point.

Sorry, but the relevance of that statement is rather lost on me. At face value the only things it tells me are that:
1. The audio side of the TV aux input works OK.
2. You do know how to switch the TV to the aux input.

It says nothing about:
1. The condition of the video side of the TV aux input.
2. Whether the RPi's analogue video out is working.
3. The goodness of the video cable.

Do you have or can you borrow any audio source with outputs on RCA phonos? Test your video lead by connecting one of those audio outputs to one of the TV aux audio inputs.

[skaldicpoet9]

Haha, sorry. Yeah, I understand the disconnect. I made a couple of assumptions mainly:

1) The Pi is brand new and the chances that the analogue video out being faulty were slim.
2) Both of the audio inputs on the two tv's I was using worked just fine. This was just to see if the a/v inputs on the t.v. were faulty, well the audio ones mainly as I didn't have another video cable for a control. The chances of the both the video inputs being kaput when the audio on both t.v's functioned was iffy at best.
3) The video cable I was using was faulty because it was a second hand Radio Shack cable purchased from Goodwill.

I ended up finally getting around to driving out to Goodwill and testing out a few different video cables, and of course, it was the damn video cable. Sorry for the roundabout everyone. I completely assumed that the video cable worked (I've never experienced a video cable not outputting a signal, not to say it doesn't happen) and so figured it was some other problem. I excahnged the video cable for another one and it works just fine now. Thanks to everyone who responded though, I appreciate it, even if it was a fool's errand on my part :/

Do you have or can you borrow any audio source with outputs on RCA phonos? Test your video lead by connecting one of those audio outputs to one of the TV aux audio inputs.

I know I've solved the problem, but just for clarity: what exactly do you mean by this? How do you use this test the video lead exactly?

[drgeoff]

Do you have or can you borrow any audio source with outputs on RCA phonos? Test your video lead by connecting one of those audio outputs to one of the TV aux audio inputs.

I know I've solved the problem, but just for clarity: what exactly do you mean by this? How do you use this test the video lead exactly?

Although ideally the cable type in a video cable and an audio cable should be different, either of them will carry the "other" signal well enough over a few yards for test purposes. Thus you could have tested the video cable by connecting it between a known working audio source and a known working audio sink.

[skaldicpoet9]

Whoa, are you saying you can send audio over an composite video cable in a limited capacity then? That's awesome, I didn't know that.