Have you ever received a gift, like a VCR or DVD player, and realized that your television didn’t have the kind of input you needed to use it right away? Your mind flashes back to the day you bought the TV ten years ago and wonders, maybe that’s what that sales person was talking about?
Connectivity is an often overlooked projector feature, but in some cases it can be a crucial one. Projectors like NEC’s LT245 and LT265 include most of the options you will want for business use, including network and wireless compatibility.
Connections Tell a Story
You can often tell the sophistication of a projector by looking at the kind of inputs it supports. If it has an Ethernet connection, it’s most likely network compatible, if it has a PCMCIA card slot, it’s probably able to handle wireless applications, and if it has component video it is likely to be HDTV compatible.
Let’s talk a little more about some of the more common connectivity options for business projectors, including computer, video, and audio connections.
VGA (Dual Component or switchable)
VGA is your standard monitor cable. It’s used for LCD and CRT computer monitors, as well as computer projectors. With the rise in popularity of home theater, many VGA cables now offer a ‘dual component’ feature which allows the VGA input to double as a component input (see below) for carrying HDTV signals. Some VGA ports can also be ‘switchable’, which means they can be either an input (computer to projector) or switched to output (projector to external monitor) which allows for an additional monitor to display the computer source.
Digital Video Interface (DVI)
DVI cables look a little like a standard VGA cable, but they are slightly larger. Under ideal circumstances, the DVI cable creates a ‘digital to digital’ connection between video or data source and display device. DVI is slowly becoming a standard, and would be a good connection to have to help future proof your projector purchase. Some DVI ports can be used to transport high-definition video as well, but if you plan to use your DVI input for video, be sure it is HDCP (High-Definition Digital Content Protection) compatible. If you use your projector strictly with a computer, this will not be an issue.
HDMI is another type of digital connectivity which you may have heard of. HDMI cables can carry high-definition video signals just like DVI, but they are smaller and also carry full 24bit 8 channel audio. This is type of connection is also becoming more popular, but it is primarily designed for home theater applications.
Ethernet (Network addressable, RJ45)
In the best case scenario, an Ethernet connection allows users to “hang” their projector on an existing network infrastructure. This allows users to access to network files via the projector remote control, and presentations from anywhere you can get an IP address … even over the internet. Only a few select manufacturers (inluding NEC) have been able to implement this kind of functionality, due to a lack of computer processing power in the projector. However, the benefits of remote operation and management are still a powerful motivator for purchasing a network compatible projector.
Understanding projector networking can be a little daunting for the average user, but network administrators will quickly understand the benefits from remote operation of projection equipment. Projectors that are networked are easier to maintain, and are even easier to operate for users accustom to accessing a network.
Wireless Compatibility (802.11b or 802.11g)
For road warriors that prefer to travel light, wireless functionality allows you to travel without the weighty VGA or DVI cables. PowerPoint presentations are automatically wirelessly ‘beamed’ to your projector, making for nearly seamless wireless images. The new 802.11g utilizes the newer and faster standard, allowing for display of some slick transitions. Some 802.11g projectors may be backwards compatible with 802.11b hubs as well. Wireless projectors are also very handy in meeting rooms because they can allow for simple collaboration between attendees without plugging and unplugging from the projector between presentations.
PCMCIA (Memory card slot)
If you want to travel not only without wires, but without your computer as well, a PCMCIA memory card slot on your projector can be used to run a presentation from a compatible memory card. The memory card is simply slipped into the slot with the fully loaded presentation, and forward and backward navigation of your presentation can be managed from your projector remote. Some PCMCIA card slots can be used to add network or wireless connectivity as well, with specially designed adapters.
An RS-232 serial connection allows users to operate their projector from a connected serial network (not to be confused with your LAN). Operations that can be preformed include maintenance reports (checking lamp hours) and full projector control (switching on and off) all through a connected computer.
USB Type A or B(Universal Serial Bus with hub connector)
This type of connection allows you to plug your mouse directly into your projector. Your projector then can operate like your computer desktop. This is a popular feature when the projector is used in desktop situations. Some USB type A connections can also be used with a USB key, which can store files (including short bits of MPEG video on more robust cards) such as a presentation.
Analog audio is the standard audio input that usually accompanies basic video connections. Computer projectors do not typically have powerful speakers. Larger conference room units are likely to have better speakers than smaller portable projectors.
Stereo Mini-Jack (3.5 mm)
Allows users to play computer audio through small projector speakers. External computer speakers may be preferable if sound is a vital part of your presentation.
Variable Audio Out
Variable audio out is an option that allows external speakers to be controlled by the projector remote control. This is a valuable option for presenters that frequently use audio in their presentations, such as teachers.
Composite Video (RCA)
RCA cables are among the most common, and will probably look familiar. Typically, they are color-coded: red, white, and yellow. Red is for right channel audio. White is for left channel audio. Yellow is for video. Composite video is the lowest quality cable for video because it passes the entire video signal on one cable. However, it is still very common. Most video camcorders, VCRs, and DVD players, and even some computers (my iBook has a composite out through the audio jack with a $15 adapter) will still have composite inputs. It’s still your safest bet if you are planning to display video.
S-Video or Y/C
This cable might also be referred to as a SVHS cable and can be found on most televisions, DVD players, and digital cable and satellite set top boxes. S-video cables differ from composite cables in that they split video signal into two different components: luminance and chrominance. The S-video cable will offer marked improvement over a composite cable, and is nearly as common as composite.
Component cables look a lot like composite cables, but they are red, blue and green, rather than red, yellow and white. However, where a composite cable carries the entire video signal on a single cable, component cables split the signal in three. This connection gives a superior image over composite or S-video connections, and can carry analog high-definition signals. You might see the signal itself referred to as either Y,Cr,Cb, or Y,Pb,Pr.