W. Robeti Barnard Montana State College Bozeman
A Remote Control Switch for Proiectors
The simple low-voltage relay operated device described in this article makes practical the starting and stopping of a motion pict,ure of slide projector from a remote position. The use of a single slide, or showing a motion picture "clip" or film, at any time during a lecture is now practical since all details pertaining to the screening may be arranged for in advance. If this device is used as an accessory to a slide projector with remote controls such as a Kodak "Carousel," fully automatic operation is possibl=. Most of the new projectors have high lisht outputs, making the total darkening of a room unnecessary. Maximum projection bulb life is obtained by cooling the bulb as
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rapidly as practical after use. Whenever possible, the projector should be run with blower on and bulb off after each showing until the bulb is cooled. Note the modification to the ac line input for the motion picture projector. In the case of the Bell and Howell projector, a separate cord similar to that used on television sets may be substituted for the short lead coming from the projector amplifier. This modification is necessary for sound films as the amplifier power sill be shut off when the relay coutrol is switched to '
