International projectionist (Jan 1959-Dec 1960)

provides a balanced line condition from any non-sync source. Mounting brackets and interconnecting wiring complete the assembly. Mounted in the optical reproducer, the photoelectric cell coupling unit receives the signal from the photoelectric cell and converts it to conform to the electrical characteristics of a magnetic head. The signal can then be played through a conventional magnetic sound system. The unit is small in size and is shipped with three different types of brackets, which provide mounting facilities for this com Modern Projector Efficiency Projectors such as the Brenkert BX40, BX-60, and BX-80, and the new Century models H and HH employ large-size stars and cams for the highest possible degree of image steadiness and long life. The Century and Brenkert projectors furnish the best answer to European critics of the small star-andcam size of most American mechanisms! To mount these or other fine mechanisms on Western Electric universal bases or the somewhat similar Motiograph H bases is sheer folly — yet, it is being done every day. Likewise, the use of old-style Simplex pedestals with heavy modern arclamps is simply stupid. Lamps were much smaller in the days of the Simplex Regular and Super mechanisms. The light-weight columnar pedestals were adequate 20 years ago, but they fail to meet the exacting requireents of high-powered wide-screen projection. Not all machine-vibration problems are solved by sturdy bases, however. Rigid, well-balanced supports we must have; but not even the sturdiest of them can completely overcome the effects of dynamically-unbalanced fly-wheels, bent shafts, lop-sided shutters, motor armatures, and drive couplings. Rapid vibration of a projector, when it shows up on the screen, may either blur the finer pictorial detail of the image or cause the picture to dance or tremble. Lenses, intermittent movements, and even the prints have been blamed for projection defects which were ultimately traced to machine vibration! Telephone Diagnosis of heart ailments are a possibility with new, 5-lb. transistorized unit which transmits heart sounds and electrocardiograph signals via phone — without any patient-to-phone connections. Developers at U. of Kansas Medical Center say device should solve most problems of phone consultations between heart specialists. Patient, with transmitter attached sits next to phone mouthpiece. ponent in any of the more popular optical reproducers. A potentiometer permits adjustment of the photoelectric cell polarizing voltage to permit balancing optical sound level between projectors, thus the level balance of the magnetic system need not be disturbed. Terminals on the face of the unit may be strapped to obtain three optional curves at both the low and high ends of the response spectrum to achieve the proper roll-off for the particular auditorium. A selection of output terminals allows three different output levels to be utilized: zero db, -6 db, or +6 db. Automatic Channel Selection The preselect unit is mounted on the magnetic reproducer penthouse. It provides instant selection of the appropriate type of sound (four-track magnetic, optical, or non-sync) at each projector. It automatically connects the signal to the correct channels and terminates unused channels in a resistive load. Level adjustments are furnished for each sound track, so that balancing between projectors and channels is easily accomplished. The unit is shipped with a 50foot captive cable installed, threaded This simplified functional block diagram illustrates how the Magoptical Converter is installed in a typical theater sound system. Components of the converter assembly are shaded. */ •fotyf/ a ■*> •*•/ ■*■/ •*•/ #1 REPRODUCER 4 #2 REPRODUCER t I .' I CD ' , •?y ■£■/ •?■/ <■/ ° / <*■/ :•: OPTICAL : : n . MC:;Sx?3£ 4TR: > . < MAGNETIC;:: :PRE-S'ELECTS'wifCH:x:;:: a NON sync: Si OPTICAL;: ••x*':" ^MAGNETIC PRE-SELECT SWITCH " v w " REPRODUCER -CHANGE OVER # I PREAMP # 2 PREAMP #3 PRE AMP #4 PRE AMP MASTER GAIN CONTROL #1 POWER AMPLIFIER #2 POWER AMPLIFIER #3 POWER AMPLIFIER #4 POWER AMPLIFIER SPEAKER #1 SPEAKER #2 SPEAKER #3 SURROUND SPEAKERS INTERNATIONAL PROJECTIONIST JANUARY 1959