SECRETS OF SUPERIORITY

[Music] while filmo sounds can speak for themselves they cannot explain the reasons for their proved superiority no one feature of design or construction makes the filmo sound so outstanding it's the combination of many features and bell and howell's years of experience in design and construction of motion picture equipment that make the filmo sound the accepted leader of the field must look behind the scenes to find the truly important reasons for the supremacy of filmo sounds behind the product are these incomparable facilities [Music] fundamentally a motion picture projector consists of a source of light with a suitable optical system a mechanism for moving the film and the necessary devices for the reproduction of sound the light source of most projectors is an incandescent lamp for real efficiency and maximum screen brilliance the filament must be precisely aligned with the optical system no two projection lamps are exactly alike but in the projector all lamps must be identical the filament of a new projection lamp may be high or low or leaning any variation wastes valuable light even production pre-focused lamps are subject to serious variations when we get it our lamp is no better than others of the same brand but inspection rejects all but the best having passed the ridgid inspection it is placed in this optical aligning machine the filament magnified almost 300 times on the target is adjusted to center perfectly in your filmo sound in this truly pre-focused position a rugged accurate ring is electrically brazed to the lamp base the result a lamp which exactly fits every filmo sound see how the guide pin locates the lamp in one direction while the centering ring locates it in the other this assures the ideal placement of every lamp in every filmo sound the only lamp that can be replaced while hot the lamp perfectly aligned the efficient condenser concentrates the light on the film unique among condensers this one is instantly accessible for cleaning the auxiliary condenser actually increases the light as much as 33 percent with certain projection lenses with 85 percent of the available light always assured by the permanent position of the lamp socket only 15 percent is subject to adjustment in the field when lamps are changed convenient as the condensers the projection lens is quickly shifted in or out for approximate focus then revolved on its micrometer thread for a needle sharp picture accessible as they are all of the elements are perfectly aligned in this rugged die cast aluminum housing since the motion picture is a series of still pictures the light must be cut off while each picture is replaced by the next to eliminate flicker two extra interruptions are needed this is accomplished by a shutter which covers the aperture not only during the movement of the film but two other times while each picture is being projected a barrel shutter might be used but its thickness impairs efficiency by separating the optical elements and its construction causes uneven illumination see how the light is cut off from the top and bottom this results in a hot strip across the center in low illumination above and below the fillmo sound shutter is engineered to perfection the close-coupled single blade disc with a sixty percent open section gives maximum light with uniform distribution its three revolutions per picture make flicker imperceptible just another detail of filmo sound and here's the most important part of the projector the time proof fillmo mechanism a universal motor of generous size is an integral part of the projector it's designed for exactly this purpose and no other an electrical governor maintains constant speed with remarkable accuracy only two percent variation for line voltage changes as great as 20 percent while we're examining the motor let's take a look at the armature shaft here's one of the motor bearings all the high speed bearings in the filmo sound are ball bearings of the finest quality no attention needed for these they're protected from dust and factory sealed in lubricant the fan is next permanently fixed to the armature shaft when the motor starts the fan must revolve only when the fan is operating can the lamp be lighted equally effective forward or reverse it completely protects both the film and the lamp here's the most important feature that distinguishes the filmo sound from all other projectors a gear gears not belts not chains but enduring positive precision gears drive all the moving parts of the filmo sound at the aperture a mechanism is needed to move intermittently the successive pictures into position several types of intermittent mechanisms might be used one type is known as a claw this term is often misapplied to the shuttle intermittent but there is a real difference the claw certainly does deserve its name another a drunken screw is used in sprocket intermittent projectors even if this were the theater geneva cross movement with which it's often confused its 16 points of wear on the star in the sprocket would still make it undesirable if all these points wore equally the picture would be unsteady but since they wear unequally the picture jump is even more pronounced the fillmo sound shuttle not claw is made of one piece of hardened steel with identical cam and shuttle surfaces positioning every frame unexcelled steadiness is assured with the shuttle teeth this close to the aperture unsteady projection resulting from film shrinkage is entirely eliminated straight in straight down straight out this is the true shuttle action no matter how rugged or precise the machinery its lifeblood is oil the lubrication system of a projector is of vital importance it's worth knowing what happens to the oil it might be like this the filmo sound leaves nothing to chance heavy felt reservoirs retain large supplies of oil then directed to every part requiring lubrication the felt also serves as a filter for oil mixed with dirt is worse than no oil at all as each moving part touches an oil wick just the right amount of oil is released by contact even if oiling were frequently neglected large quantities of oil held in the reservoirs ensure adequate lubrication hardened and ground steel sprocket teeth moved the film to the aperture and to the sound drum unique in design and absolutely fool proof the bell howell safe lock sprocket guard is your insurance against film damage when the film is threaded under this guard it's either correctly engaged or it's just not threaded in either case it's perfectly safe on the filmo sound there is no need for gadgets it's just built right from the inside out while the film moves intermittently past the aperture 25 frames ahead the accompanying sound record must move with absolutely constant speed past the sound scanning beam before the film reaches the scanning beam every trace of intermittent movement must be eliminated even with filmo sounds positive sprocket between the intermittent and the sound drum enough variation to spoil the sound would still exist but bellen howell has the solution to this problem the oscillatory stabilizer while the film is moving as a part of the perfectly balanced filter wheel the oscillatory stabilizer short circuits film speed variations by passing them not to the sound drum but back and forth from roller to roller and to complete the ideal projector the bell howell constant tension take up no matter how large or small the reel just the right pull is exerted it's entirely automatic and self-compensating since the torque depends on the weight of the reel and film press the lever lift the spindle and it takes just two and a quarter minutes to rewind sixteen hundred feet of film the secrets of superiority are secrets no longer [Music] filmo sound speaks for itself you