First, the projector should be DATA and VIDEO compatible. This is the de-facto standard in today’s projectors, but it never hurts to ask. The physical types of connectors that are common are:
• DVI input– (specialized connector) – A computer-type input that uses a digital signal instead of the analog for a cleaner image. Not a common interface – yet.
• COMPUTER IN (HD 15-pin) {1-2 inputs}. Also called a ‘VGA’ input, this standard analog input accepts computer signals.
• VIDEO input
- Composite - (Either BNC or RCA connectors) - with BNC being the better choice because it ‘locks’ the cable in compared to RCA, which simply plug in and pull out.
- S-Video (a.k.a. S-VHS) – a multipin input that separates the picture and sync information from the color information. Better quality than composite.
- Component – (Typically BNC or sometimes RCA connectors) – again, with BNC being the better choice. Several ‘flavors’ of component – RGsB, RGBS, RGBHV, YUV, Y Pb Pr. These are the most common types and offer the best quality picture. Component means to divide up the information into separate useable signals that are recombined at the projector for maximum quality.
• AUDIO input (usually mini-phono jack) - this is not necessary if you will run audio through a mixer.
• RS-232 (remote control protocol) {1-2 inputs} - this allows for third party control hardware/software such as Crestron or AMX. Many churches only use the wireless remote control and never bother using RS-232.
• USB - some projectors allow a USB mouse to be used for controlling the cursor that is found on many remote controls. Note that the USB connection isn’t used to send video to the projector.
• Flash Card slot –
• RJ-45 –
• PCMCIA card slot –
This is a very basic description about the common input types found on today’s projectors. It serves as a ‘launching pad’ to help in the education of the technology, and is not intended to be the final answer. After all, technology changes every minute!
- Some portable projectors allow a flash memory card (like the ones used in digital cameras) to hold a PowerPoint show on the card so that a laptop isn't needed to do a presentation.
- Some projectors now allow a “CAT-5" connection for networking the projector. The typical benefits are the ability to check lamp status, projector temperature (too hot usually means a clogged filter needs cleaning) and on/off controls.
- The ability to use a wireless network card, such as the type used in portable laptop computers, is beginning to be seen on projectors. This functionality allows the projector to be tied into a network, and be seen as a device, much like printer can be seen as a device on the network. The wireless portion also means no need for any of the cables mentioned above – the PC’s signal is sent through another PCMCIA wireless network card, too!
- A few projectors use this slot to insert Compact Flash or Microdrives for playing back images without a laptop.