The challenges of supporting students and faculty who use computers and mobile devices in the classroom seem to have only grown more numerous since the dawn of data projection. In the early days, teachers were the only ones using a computer in the classroom, so connection to the screen or projector was no big deal. Fast-forward to today’s classrooms where students are expected to create and deliver presentations as early as the First Grade, and you’ll find an ever expanding universe of devices used by both students and staff that need to connect to the display.
IT departments and AV suppliers have thrown plenty of “solutions” at the classroom to accommodate the onslaught of devices needing to connect to the big screen. Video switchers, complex control systems, patch panels and adapter cables and even, in desperation, document cameras aimed at laptop and smartphone screens. But what happens when these complex systems have an “off day”? Teachers lose significant teaching time just managing all of these connections, which reduces students’ focus and productivity, while delivering less than optimal results.
Many tech-savvy educators saw the Apple TV as a wireless solution when the device was upgraded to streaming capability in 2010. But the promise of wireless display connection quickly wore off and gave way to the harsh realities of an eco-system built around paid content. Yes it’s true—Apple TV could technically support streaming content from any device but the company holds a vested interest in restricting this capability to its own devices.
The past 2 years have seen a proliferation of devices that purport to address the challenge of wireless presentations and display capability. The solutions range from those built on Wi-Fi transmission to closed-circuit wireless video transmission, with plenty of benefits and pitfalls alike. Let’s take a closer look at how these solutions work and which is the best for your classroom.
One group of wireless display devices relies on the use of a “dongle”, or adapter that plugs into the computer and sends video to a separate receiver. Dongle-based systems fall into one of two categories; those which plug into the HDMI output of a computer and others which connect via USB. Right off the bat both categories of dongle-based solutions work only with Windows and Mac laptops and computers, or at least those that have HDMI or USB connectors on them.
Dongles which connect to a computer’s HDMI output are the simplest and “dumbest” of such display adapters. Since they are essentially HDMI video broadcasting devices, there is no centralized connection or control functionality as there would be with a two-way system. These systems are purely ad hoc, with a first-come, first-served logic. Better suited to consumer applications where a DVD player sends a signal to a projector, they have nonetheless been pressed into service for corporate and educational applications where their inherent limitations are soon exposed.
The USB-based dongle works on a slightly different principle as it transmits the display data before it’s rendered by the computer’s video graphics adapter. Eliminating the one step of conversion is great, but the real benefit is that the USB interface now permits two-way communication that can be employed for connection management. The downside is that these systems are subject to the vagaries of hardware compatibility between the USB device and the host computer—not to mention that they still require a Windows or Mac PC with full-size USB ports to connect to. Not accommodating to mobile devices.
Enter the world of streaming media over Wi-Fi; a technology that has been part of the way we connect to the network for two decades. Wi-Fi—like Ethernet—was never meant to carry time-sensitive material like audio and video, but consumer demand forced engineers to find a way. Today we use Wi-Fi at home to stream music, video, and access Internet-based content and expect it to work flawlessly, which it most almost always does.
The latest spate of wireless presentation and display devices don’t require a physical connection to the computer, relying instead on Wi-Fi to send the video signal to the receiver. This approach opens up a whole new set of possibilities, especially for devices that don’t have a standard USB port. It also reduces the expense of buying and maintaining dongles and adapters, and makes switching between presenters quick and easy.
The way these wireless display devices connect to your existing equipment can vary considerably between brands, and bears careful review. When it comes to connecting to your projector or screen, you’ll want to have the option to connect with either VGA or HDMI. Some devices offer only HDMI, which is great for connecting to the latest projectors and screens but likely not for many of your existing classroom projectors which generally have VGA connections.
Another critical feature to watch for is a wired Ethernet connection between the device and your existing computer network. Adding the display device to your network with a wired connection is always preferred over wireless because it reduces the amount of radio traffic and increases the quality of the video stream. Users still connect to the network wirelessly, just as they always have; only now the wireless display device shows up much like any other networked device such as a printer or hard drive would.
Command & Control
Hardware is only one component of your new wireless display device installation; software is the other, and perhaps more important half. Users have a tough enough time just creating and presenting their content without having to worry about configurations, options and confusion related to the software client that needs to run on their computers. Look for software clients that are clean, simple and above all easy to use. Avoid gimmicky features like split screens and file sharing which sound may sound neat but doesn’t provide useful functionality to the presenter and their audience. Focus instead on software that provides a seamless user experience for the presenter and the moderator.
As a teacher you’ll want to have the option to moderate presentations so look for software that allows password-protected access to a moderator or conference mode. This should allow you to see who’s logged in to your classroom’s display device and control when they start and end their presentations. Ideally, the software should allow you to preview what’s on the users’ screen before you activate their display, ensuring that the presenter has loaded the appropriate presentation on their device.
Another important feature found on some wireless display devices is the ability to share a presentation remote, keyboard or mouse between presenters. This works by plugging the HID (Human Interface Device) compliant device into the wireless display device, instead of directly into a user’s computer. The display device then hands off that device to the user who’s sharing her screen at the time. Effectively, one remote control or wireless keyboard can be shared among the class as users take turns displaying their screen. No more time wasted with plugging and un-plugging an HID for each presenter.
Don’t forget the Audio
So far we’ve focused on the video, which is fine if you are connecting the wireless presentation device to the screen with an HDMI cable, since it carries both video and audio. But if you have a legacy VGA projector or display in your classroom, the display device needs to have separate audio outputs to connect to external speakers. Otherwise, forget about showing videos or other content with sound as the audio will only be coming directly from the laptop speakers.
At the very least the wireless display device should offer stereo audio outputs that can be connected to external self-powered speakers. A decent pair of computer monitor speakers can be had for under $50 and a great pair of entry-level professional studio monitors for under $200. If you intend to connect a 5.1 surround sound system to your setup make sure that the wireless display device has an optical audio output that sends digital audio to a receiver or surround speaker system.
Wireless is here to stay and in fact is the way forward for nearly every form of communication. With smart phones and tablets becoming cheaper, more powerful, and more ubiquitous, wireless environments need to accommodate the BYOD (Bring Your Own Device) revolution. The time has come to cut the video cord in the classroom and eliminate the restrictions imposed by a physical connection to the screen or projector. Imagine students presenting instantly from their desks or the front of the room without burning through precious teaching time passing USB drives with files loaded on them or disconnecting and reconnecting their device to the display. Remove the last vestige of the “computer age” by eliminating the need for cables, adapters, settings, and configuration and turn your focus back to teaching.