The Film Daily (1930)

GREATER POWER POSSIBLE WITH 50-WATT AMPLIFIER A 50-watt Powerizer amplifier which permits greater volume without any loss of tone quality is announced by the Radio Receptor Co., Inc., of New York City. The device incorporates two UV-845 power tubes and two UX-866 mercury vapor rectifier tubes. Full-wave rectification is used, and the 50-watt tubes arc arranged in push-pull. The Powerizer is arranged in three panels. The lower panel contains the power supply and push-pull power sU:ge. The middle panel contains a two-stage driver or voltage amplifier. The upper panel has a main switch and attenuator, as well as a voltmeter and control switches, so that either high or low line voltage may be compensated for by the operator. The amplifier may be employed in various combinations with microphone preamplifier and radio or i phonograph input. It is claimed that the quality of amplification obtained with the 50watt Powerizer is far superior to that obtained with the usual amplifiers of less power. Proportional Aperture Gate for Normal Images Chicago — Problem of projecting normal images from sound-on-film is said to have one solution in the Proportional Aperture Gate now being manufactured by the Chicago Cinema ', Equipment Co. for use with its equipment. Apertures for both normal | and sound-on-film are contained in a single plate of hardened steel, mounted in the projector die casting so that either aperture may be shifted into exact framing place. Movement 'he accessible lever up or down is all that is necessary to bring the correct aperture into place. Both apertures are formed with a degree of accuracy such that the projected \\ images will be true to form, size and pi oportion. Clean Screen Held Important To Proper Sound Projection iSyncrodisk Junioir Device Sells for $150 Per Pair Syncrodisk Junior, a new reprotion device being manufactured by the Weber Machine Corp., which also out Syncrodisk Turntables, Syncrodisk sound-on-film and other talkling picture devices, will sell at $150 pair it is announced by the company. The new apparatus is a turntable built along the lines of other 'Weber machines. It has been simplified in design and construction that quantity production makes possible ■tin low price including pick-ups and ngeover fader. Either the Audak or l-'.rla pick-ups can be secured. "Keep your sound screen clean," is the advice given exhibitors by R. H. McCullough, sound engineer for Fox West Coast Theaters, who asserts that this is important to the efficient projection of talking pictures. "Many theaters," he says, "are still using the Transvox Screen, which was the first sound screen to be used with sound reproducing equipments, where the horns were placed behind the screen. The Transvox screen material collects dust and dirt very easily. This type of screen should be dry-cleaned every ninety days and vacuumed twice monthly. The next transparent sound screen, which was supplied with E. R. P. I. sound equipment was the Da-Tone-X Screen. This is a rubberized perforated material. Definite instructions are, never to use ordinary soap for cleaning these screens, which will invariably leave clouds or streaks. "The question is asked — Can the Da-Tone-X Screen be washed and citsned in a satisfactory manner? TheDa-Lite Screen Company, Chicago, Illinois, furnish a cleansing powder in a concentrated form. _ Two tablespoons of Da-Tone cleaner is put into each gallon of warm water. Two one gallon pails are necessary to clean a Da-Tone-X Screen and also two 1 -ounce soft sponges. The cleansing fluid in one pail, and plain water in the other pail for rinsing. To clean a Da-Tone-X Screen, always start at the top of the screen, taking a section of three or four feet and work downward. Do not make a lap at the seams. The sponge should be kept free from surplus water. Do not allow water to run clown the screen. Water should be changed frequently. "Do not expect to get the surface clean the first time over. Follow the first washing with clear water without the cleaner and a clean sponge and go over the entire surface as before. Never wash the back of the screen. Never apply DaTone iner in powder form directly to the surface, as it is too strong. The I ); -Tone-X Screens should be washed as often as they begin to show streaks or spots. Water will not discolor the surface or reduce its reflective qualities. The Da-Lite Screen Com p; ny highly recommend that their make of screen be washed as often as necessary, which is governed by local conditions. "We have installed a few Walker Sound Screens. The Walker Screen Co., will not recommend that their ir.;ke of screens be washed. They advise that the screen be brushed at regular intervals of twice monthly with a soft Goat's hair screen brush to obtain maximum efficiency. The method of brushing is to start at the top, brushing across the width and in coming down over the screen surface with the brush, care should be taken to avoid unbrushed laps. "The first sound installations were regarded as novelties and projection was forgotten. E. R. P. I. insisted on using the transvox screen, which absorbed about twenty per cent of the projected illumination, which ruined projection in many theaters. Where sound equipment was first installed, additional equipment, including larger Motor Generators and high intensity lamps, had to be installed to compensate for the light loss, due to the light absorption of the transparent screen. This condition has been greatly improved during the last year with much research work for the perfection of an ideal sound screen without light loss. Good projection is essential in every theater. The picture must be clear, sharp and unclistorted. The old silver and gold surfaced screens are a thing of the past. The white surfaced screen has retained its position even with transparency and with perforations to transmit sound. The white surfaced, perforated sound screen gives a true, natural image without the fade-away on the angles. "The masking of the picture screen is of great importance. During my visit to many theaters I find the masking either sagging at the top or bottom of the screen, and on many occasions I have noticed the side 150O Splicers Port Jefferson, L. I. — More than 1,500 Griswold Film Splicers are in constant use in theaters throughout the world, it is claimed by the Griswold Machine Works. Exhaust Fans Available for Projection Booths Meadville, Pa. — Exhaust fans for the projection booth are an important item these days. The Davenport Mfg. 1 is manufacturing an exhaust tan which it is claimed exhausts from 500 to 4,000 cubic feet a minute depending on the size of the vent pipe. The fan is simple and compact, it is stated, and can be installed horizontally or vertically. maskings slanted to the keystone of the aperture. "Some projectionists, who see the screen more than anyone else, notice detrimental things of this nature and they never say a word about it, and as long as the picture is on the screen and the sound is coming through, everything is O. K. in a small way. Boys — we must be on our feet, look, besides listening and be positively sure that the picture looks right. The picture should always be neatlv masked." FLAME PROOF IT JUST WONT BURN HEWES-GOTHAM CO. 520 West 47th St., New York TeL Chickering 4531 CINEMA Write For Trial Sam/We TALKING NEEDLES WALL-KANE NEEDLE MFG. CO.. Inc 3922 14th Ave. Brooklyn, N. Y FIRE-PROOF WATER-PROOF Ruscus Trees. Hedges, Flame-Proof, also WaterProof for indoor and outdoor use. Artificial Flowers, Plants. Trees. Vines, Iron Wrought Decorated Stands for Lobby Theatre and Hall Decorations Illustrated in Our SEASONABLE CATALOGUE No. 3. MAILED FREE ON APPLICATION. ■ Suggestions and Estimates Cheerfully Furnished. FRANK NETSCHERT, Inc. 61 Barclay Street New York, N. Y.