In search of a modern technical setup for a classroom / meeting room

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Hi everyone,

I am a teacher in upper secondary education at a small European country. A typical classroom at our school is equipped with a overhead projector and a stereo sound system. You bring your own device, hook it up via HDMI-A and you are ready to go.

This is already a quite capable setup but it will be “improved” over the next years. A horrible proprietary “modern” solution was tested in one class room at our school. Luckily there was a general backlash against the proposed solution preventing it from adoption.

This incident motivated me to take action. My goal is to propose actual improvements.

Let me explain how the current setup is used by advanced users. They bring two computers. One is typically a tablet or a convertible with a pen. This device is hooked up via HDMI sharing its screen with the projector and is used for showing slides, writing like on a blackboard etc. The second computer, typically a laptop, is used as a secondary monitor (not shared with the students) mostly for looking at guiding notes for the lecture and for working on administrative tasks.

Obviously two computers for this scenario are not only overkill but also inconvenient, because both have to be hooked up for power and their has to be some data synchronisation service in place.

To eliminate the need for a second computer in the workflow above I bought a pen tablet display (wacom cintiq), a HDMI-splitter and a USB-C dock with a power supply. Then I hooked everything up in such a way that the tablet display mirrors the projector image. If it works, this is a very nice setup needing only one laptop connected via USB-C (including power delivery) giving the user a pen tablet display as a secondary monitor which is shared with the projector. Even if the pen functionality is not used, one gets the benefit of a secondary monitor which mirrors the projector, leaving the laptop monitor free for other things. With mainline Linux this setup is plug and play. You don’t have to install anything. I am quite happy with this setup and find it promising for proposal.

But the devil is in the detail. The HDMI-splitter copies the EDID of the monitor which it sees first and holds on to it, as long as it stays powered on. In my setup it copies either the pen tablet display EDID or the projector EDID. The audio over HDMI only functions with the EDID of the projector. This means if someone temporarily cuts the power of the HDMI-splitter it is a matter of chance, if audio will work or not, which is not acceptable.

Then there are computers which will refuse to work as expected with the USB-C-dock. I have no idea what so ever why this might be the case.

I strongly believe that the way forward is one single USB-C connection and behind this connection only standard components with mainline kernel support. No proprietary apps, no could, no subscriptions. Only one cable to rule them all.

How would you equip a classroom / meeting room for a bring your own device scenario?

What are your experiences?

Please show me the path to interoperability and stability!

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There are petter and worse (and craptastic) video-splitters.
You could get something high-end like an HDFury Integral2, those let you manage EDID as needed.

Is it an actual USB-C Dock or a Thunderbolt 3/4 Dock?
I found the HP Gen5 USB-C Docks to work with the Steamdeck, HP and Dell laptops. Some may complain about being connected to a slow-charger (which can be ignored in this setting IMO).

  • SMART is extremely overpriced for what it is.
  • Large-Format displays for commercial installations can work (think iiyama TF6539AS for example), we used them on little carts on an assembly floor for displaying CAD-drawings during assembly.
  • Large-Format Monitors with integrated computers (OPS- or SDM-port) could be worth considering (Examples: IIyama TE8613A, Panasonic SQ2H-series)
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Thanks for the replay!

I definitely have to check out higher-end options for HDMI-splitters. Preferably there is one with programmable EDID using FOSS-tools on Linux. I am eager to learn more about these devices.

It is a generic no-name USB-C dock with 1x HDMI-A, 3x USB-A, 1x 3.5mm Audio, 1x Gigabit Ethernet, 1x SD-card reader, 1x USB-C power input. No Thunderbolt capabilities I know of. I chose it because it has the needed ports and has a detachable USB-C cable (so I could swap it out for a longer one). Maybe there are docks featuring multiple HDMI-A inputs with integrated splitter functionality including proper programmable EDIDs?

For our school I think a “dumber” solution may be smarter long-term. I am not comfortable with proposing shared devices which need a full fat OS installed on them (even Android) to work properly. My fear is that nobody is willing to maintain the OS long-term and that there is limited cross-platform FOSS support to begin with. I’d rather propose a “dumb” pen display with touch capabilities (i.e. wacom cintiq) which is known to work cross-platform with any device (Linux, Windows, MacOS, Android) the users bring and maintains themselves.

There remains the challange of integrating such a pen display with splitters and docks that all the equipment of the room can be comfortably and reliably accessed over one single USB-C port.

Feel free to suggest alternatives or anything I might be missing. OPS- and SDM-ports are new concepts to me.

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Nothing beats a bunch of white board markers in an array of colours.

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Could a USB-C dock that has dual HDMI outputs be an option here?

something like the Anker 553 USB-C Hub

It could handle power in for the laptop, USB and HDMI to the tablet, HDMI to the big screen.

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All our classrooms (except the test one I mentioned above) still have old school black boards and chalk in different colours. We will fight if somebody wants to remove them.

Yes, but I would also like to have both HDMI outputs mirrored, so that the tablet screen always shows the same image as the projector. Of course one can achieve the same result in software, but I am convinced that it is more convenient if the two outputs are already combined when someone connects the USB-C cable. Most users are non technical. They want a foolproof connect and forget solution. I don’t know of a dock that combines this functionality with the possibility to always prioritize one of the two EDID’s over the other.

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In the age of chemicals with unknown effects in everything, I would prefer the known quantity of chalk-dust.

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This is funny because the main reason to switch to a tablet after having used the blackboard for 10+ years, was the annoyance of chalk-dust. However I doubt if the microplastics scratched of the surface of the tablet will be any better. At least it is less annoying.

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Hdmi splitter with EDID management. Some have dip switches that let you chose how it handles the EDID.

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If whiteboard markers were bad for my health I’d be long dead by now.. Or maybe my immune system has built up a tolerance for the things? Anyway I’m still here after 20+ years of daily exposure to markers.:slightly_smiling_face:

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Thanks for the hint. This might be exactly what I am looking for. Searching for such HDMI-splitters results in multiple interesting options . Do you have experience using such devices? Are you comfortable with making recommendations?

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I only know that they exist. But haven’t used any. I was looking for an upscaler a while back. And I came across the EDID splitters.

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The Wacom display seems kind of overkill to me. This device costs as much as a laptop in my country! Do you not have SharePoint or something like that at work… I would think about using cheaper android tablets myself. But maybe you are working in a private institution

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I’m thinking of one pen tablet display per classroom permanently installed on the teachers desk resting on a height adjustable stand. Expected use during multiple hours every workday. This demands a high quality professional product. Under these circumstances the price of a laptop seems adequate for one of these tablets. I expect 10+ years of use with minimal maintenance.

On the other hand I only see a cheap android tablet being useful, if every teacher buys one, maintains it and replaces it may be every 5 years.

There are other brands offering potentially cheaper pen tablet displays like Huion and XPPen. I never used one of these myself. But they might be worth considering, if they offer comparable cross-platform compatibility and comparable build quality like Wacom. Can anyone confirm or deny this?