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1954-55 Theatre Catalog, 12th Edition, Page 344 (308)

1954-55 Theatre Catalog, 12th Edition
1954-55 Theatre Catalog
1954-55 Theatre Catalog, 12th Edition, Page 344
Page 344

1954-55 Theatre Catalog, 12th Edition, Page 344


I The Automatic Crater Positioning Central System insures that both carbons are so fed as to maintain a correct arc gap length and to keep the position of the positive crater at the exact focal point of the reflector. Thus, throughout the presentation, the screen light is always of the same color, without variations from white to either blue or brown. The proiectionist is accordingly freed from the necessity of constantly supervising the arc so that he can devote himself to the care of other technical features of proiection which require continual attention.

- National's Reflect-O-Heat unit permits the great increase in volume of light at the mammoth new screens, without a corresponding increase in heat at the aperture.

I The arc is stabilized by a stream of air which maintains a prescribed system of ventilation of the area surrounding the arc. This air iet prevents the hot tail flame of the arc from reaching the reflector, supplies enough oxygen so that no black soot is produced, and keeps white soot froin collecting on the reflector in such quantity as to absorb heat which would cause breakage.

Unit construction permits easy removal of the elements for inspection in servicing.



An Efficient, Dependable Power Supply for Your Projection Arcs

I Tliere's a National Tube 01: Selenium Plate Type Rectifier designed to matcln the requirements of every type and rating of angle trim or coaxial trim projection arc lamp. All are

lauilt in single lamp units for flexibility of

electrical connection.

I The brllliancy of your proiected pictures, Distributed by


Divinim cl Nalienal - Simple: - .lvlwevthnc

regardless of the efficiency of all other equipment, is dependent directly upon the

condition of your lamphouse reflector. The only light which can reach your screen must

necessarily be reflected to it by this mirror.

"There's A Bunch Near You"

I All reflectors gradually deteriorate to a state where replacement cost becomes

To fan/(lair Inquiry H 1/117 111mm. plum mull/mi 117: ralumr am! [mgr IIIIVIIIIFY,


I Power output adjustment to the arc, over a wide range of values while the arc is burning, is lay means 0t an external, manually operated lianci Wl'ieel on the front. Transtormer taps are provided to compensate tor changes in line voltages from 200 to 250 volts anti the complete amperage range.


insignit'lcant, since a drop of only l0% in their reflective efflciency results in a corresponding decrease in screen brilliancy, and accordingly also represents a loss amounting to 10% of the cost of your current and


Available for replacement in all types and makes of arc lamps.

1954-55 Theatre Catalog, 12th Edition, Page 344