[solved] Raspi 3B 3.5mm jack: Dual view with HDMI? Maximum cable length?

Clyde

Hi folks,

I have some questions about the 3.5mm jack of the Raspi 3B:

Can it be used for dual view next to HDMI output?
If so, how do I set it up?
What is the approx. maximum cable length for its video output?

I'm trying to figure out a way to send my upright cabinet's picture to my video projector for an audience of guests. Other solutions I'm pursuing are ~~a HDMI splitter~~ (failed already) and network streaming. This is another idea I had.

Thanks for any advice.
Clyde

edit: I finally solved it with an HDMI splitter and an HDMI-to-VGA converter. See below.

mitu

@clyde said in Raspi 3B 3.5mm jack: Dual view with HDMI? Maximum cable length?:

Can it be used for dual view next to HDMI output?

No, you can choose only one of them at a time.

Clyde

@mitu Okay, that concludes this thread. :P Thanks!

mitu

@clyde You can switch between them though, but they're not going to work both at the same time.

Clyde

@mitu Alas, that's of no use to me, as I want the audience to watch the game that is played on the cab.

ByteThis

@Clyde Awhile ago I purchased this HDMI splitter to be able to split the signal from my pi to my living room tv, and to another tv in the adjacent bedroom. It works perfect.

https://www.amazon.ca/gp/product/B0146EEQD2/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1

Clyde

@bytethis Thanks, but I think this splitter will have the same problem as the two others I tried. They don't support different output resolutions, but my cabinet monitor (1600x1200) and my video projector (1280x720) don't support each other's resolutions and/or signals. The best I got was a good picture on the projector, but a very distorted one on the cab monitor. Vice versa, the projector didn't show a picture at all when I used a resolution compatible with the cab monitor, it just displayed "not supported". That's why I added the note "failed already" in my opening post.

edit: Your splitter's description even says, "Support Two TVs The Same Time(Need Two Displays have the same size)".

ByteThis

@clyde That's unfortunate.I hope you find yourself a solution. There are all kinds of splitters available, but finding the right one for your problem seems like a cumbersome task. Good luck on your search man . :-)

iamtyce

@Clyde So glad I came across this thread! I’m attempting to do the same thing and provide HDMI (or similar) output so we can hook up a projector and clone my arcade’s view to a larger, more audience friendly view.

Maybe we could intercept the 3.5mm > RCA connection, split it and try to upscale that back to an HDMI friendly signal?

Clyde

@ByteThis Thanks.

@iamtyce said in [can't be solved] Raspi 3B 3.5mm jack: Dual view with HDMI? Maximum cable length?:

Maybe we could intercept the 3.5mm > RCA connection, split it and try to upscale that back to an HDMI friendly signal?

Maybe, but I haven't the slightest clue as to how we could do that.

Another solution I'll try is network streaming. See this thread for two alternatives that depend on Retropie 4.4. As my cabinet still runs 4.3, I'll have to install the new version on a spare sd card first.

ChuckyP

If you wanted to run those resolutions you would want to look not just into a splitter... but a DUC (Down Up Converter). This will take your HDMI input resolution and change it into an appropriate resolution for your projector.

There’s a lot of options and prices have been falling but they are still rather pricey.

Probably overkill for your intended use, but if it want it bad enough... 😁

DougA

@Clyde I know this sounds a bit of a kludge, but if your projector has a composite input, then how about using your HDMI splitter, and then passing one side of it through an HDMI to Composite converter, and then to your projector? I googled quickly, and this one supports your 1600x1200 HDMI resolution, and at under 15 bucks isn't a huge investment

https://www.amazon.com/Cingk-Converter-Composite-Supporting-Chromecast/dp/B06XKV2LMG/ref=sr_1_11?ie=UTF8&qid=1525184780&sr=8-11&keywords=hdmi+to+composite+amazon

I have a similar one that I run in reverse, so I can play antique European VHS tapes of my kids on a European VHS with Composite output on a modern American TV with HDMI input.

Clyde

@douga Thanks very much for the hint. I'm setting up Retropie 4.4 at the moment to test streaming the picture afterwards. If that fails, I'll consider HDMI/Composite converters.

Clyde

@iamtyce @DougA I finally managed to solve the problem with an HDMI splitter and an HDMI-to-VGA converter. 😄 The latter doesn't change the resolution, but my projector accepts the analog signal in contrast to the digital HDMI signal, which it refused as "unsupported". I just had to adjust the picture a bit via the projector's controls, as it was slightly off to the left and only partly visible.

A mentionable obstacle was that only one out of three HDMI splitters I tried worked with the 1600x1200 pixels DMT signal from the Pi. The other two only accepted CEA signals (see HDMI mode options in the official Raspberry Pi documentation). Strangely enough, all three splitters look exactly the same from outside apart from the brand logo.

This is the splitter that worked:

https://www.amazon.de/gp/product/B00FECY0CI/

And here's the converter:

https://www.amazon.de/gp/product/B00KW6BXRG

(Links go to Amazon Germany, but the non-Germans among you may at least learn the brand and model of the devices from them.)