Projection Devices, Continued
Video projectors are very similar to VCR units. The major difference is that
the video projector projects the image onto a screen. The video projector is
primarily a teaching device meant for small audiences. One of the drawbacks
in using this projector is how easily it slips out of adjustment.
Video projectors have the same buttons and switches as a VCR with only a
few differences. These differences are a projection lens, a focusing ring, and
input/output ports to the video cassette player.
Position a video projector so that it is not in a traffic area as this projector
easily jars out of alignment. Use a special projection cart, or ideally, mount
the projector to the ceiling in a projector rack. The projector has sensitive
adjustment dials. A misadjusted projector will project an image that appears
to have a ghost or has incorrect coloration. Adjust this projector before
actual use by aligning the three primary color dots on the screen until only
white light is seen.
Monitors are television screens connected to computers or video cassette
recorders/players to playback audiovisual tapes. Monitors have the same
adjustment features as a television. Use as large a monitor as practicable in
the classroom or theater.
Monitors have an input port, an output port, an on/off switch, a screen face,
a color balance control, and a vertical/horizontal hold adjustment dial.
Never force a plug into an input/output port. Monitors are hardy devices that
require little care beyond general maintenance and commonsense treatment.