From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Catalogue page for vibration and sound analysis equipment, including oscilloscopes, microphones, and speakers.
| Identifier | ExFiles\Box 138\1\ scan0298 | |
| Date | 30th June 1938 guessed | |
| MODEL 151 NEOBEAM OSCILLOSCOPE An increasing interest in the study and analysis of vibration has paralleled improved machine standards and efficiency in the past few years. The products described in this folder are designed to provide a practical method of vibration measurement and observation. A few other subjects are touched on because of general engineering interest and because the same equipment may be applied to the problems involved. The general subjects covered are: Vibration Noise Levels Tachometer Tuning Magnetic Balancing Checking Commutator Roughness The Neobeam Oscilloscope and auxiliary equipment described are ideally suited to the study of the above subjects and the following is intended as a general guide to their application. The following units are required on various tests: MODEL 151 NEOBEAM OSCILLOSCOPE MODEL 152 CRYSTAL MICROPHONE MODEL 153 VIBRATION PICKUP (CRYSTAL TYPE) MODEL 154-12" PERMANENT MAGNET DYNAMIC SPEAKER MODEL 156 VIBRATION PICKUP (INERTIA TYPE) MODEL 157 VIBRATION PICKUP (WAFER CRYSTAL TYPE) MODEL 151 NEOBEAM OSCILLOSCOPE: The Neobeam Oscilloscope is a highly sensitive, completely self contained, portable unit operating on the modulated neon beam principle. It is the same in all respects to the Model 150 except as output meter is built in. The built-in high gain amplifier modulates a neon column constantly excited by radio frequency. The fluctuations of the neon column are observed in the scanning mirror, thus showing the exact wave pattern of potential or sound under observation. The maximum sensitivity is 1/8" deflection at 1 millivolt input. The calibrated sweep control synchronizes the scanning mirror to the frequency observed. This calibration, together with the calibrated screen, permits frequency determinations to be made directly by applying a formula given later. Frequency determination is a necessary feature in vibration study, as will be seen later. The 0-5 voltmeter, indicating the relative amplifier output, is used to compare vibration and modulation levels. A 2 volt cycle tap from the power transformer is provided on the rear for checking purposes. Output terminals marked "Speaker" are provided in the rear of the Neobeam Oscilloscope for operation of the impedance matched Model 154 Speaker. When the speaker is not used a load is substituted across the terminals and the voltmeter measures the drop across this resistor and voltmeter are thrown in when the switch is in the "on" position. The use of the meter is often preferable in production work to provide definite limits of vibration. The Model 151 Neobeam operates directly from 110 V.{VIENNA} 60 cycle lines and comes complete, with all tubes ready for operation. The size is 8-3/4" x 10" x 13" high. Price $48.00 net. MODEL 152-Semi-directional crystal microphone. Completely barometrically compensated and moisture sealed. 65 D.B. Requires 2 to 5 megohm load impedance. Excellent frequency response from 40 to 10,000 cycles. Comes complete with 7 ft. of shielded cable. Size - 11" overall height x 4" dia. base. Price $19.50 net. MODEL 153-Vibration Pickup of the direct contact to crystal type. Transforms very small mechanical movements into electrical impulses, and is in effect a contact microphone. This pickup is not very useful for mechanical vibration study due to its very high sensitivity. Its principal field of application is in acoustic research and is intended for mounting on the outside of baffles, walls, etc. to detect sounds in tests on sound deadening materials and similar tests. It is also useful where the vibrating bodies are too light for measurement with inertia pickups. Response 40 to 3000 cycles. Size 1-3/4" x 1" x 3/4" high. Price $17.50. MODEL 154-12" Permanent Magnet Dynamic Speaker Intended for use with the Neobeam Oscilloscope in order to hear as well as see the input applied to the instrument. Very helpful in demonstrations and lectures. Audio output 8 watt capacity. Beautiful mahogany shark leatherette covering on case with polished chrome escutcheon and satin-chrome grille. 8 ohm voice coil volume control and 10 ft. cord. Size 13" x 13" x 8". Price $14.50 net. MODEL 156-Inertia type Vibration pickup is perhaps the most useful tool available for the study of vibration. When held against a vibrating body it generates electrical impulses of a wave form corresponding exactly to that of the vibrating motion. In the Model 156 the crystal is securely mounted in the housing and vibrates of its own inertia when the prod is held against a vibrating body. There being no direct contact with the crystal, it is not easily damaged by vibrations of large amplitude. PRICES Shipping Weight Model 151 Neobeam Oscilloscope........$48.00 net, 36 lbs. Model 152 Microphone.................. 19.50, 3 lbs. Model 153 Contact Microphone......... 17.50, 3 lbs. Model 154 8 watt Dynamic Speaker..... 14.50, 15 lbs. Model 156 Vibration Pick-up.......... 17.50, 4 lbs. Model 157 Vibration Pick-up.......... 28.00 Additional low loss shielded microphone or pick-up cable $1.25 (for couplings) plus 4¢ per ft. Vibration Input Voltage vs.{J. Vickers} Sensitivity Dial Calibration Curve - $5.00. BIBLIOGRAPHY: The following books and references are submitted for those desiring to make a more comprehensive study of vibration. References relating to sound and noise measurements are included because of the close relationship between mechanical vibration and noise. Books: "Vibration and Sound", by Philip M.{Mr Moon / Mr Moore} Morse - McGraw-Hill "Vibrating Systems and Sound," by J.{Mr Johnson W.M.} B. Crandall - Van Nostrand "Vibrations of Problems", by Lindsay and - Van Nostrand "Vibrating Problems in Engineering," by D.{John DeLooze - Company Secretary} Timoshenko - Van Nostrand Noise Measurement References: Electronics: "Noise Measurement," April, 1935 "Portable Sound Measurements," April, 1936 Electrical Engineering: "Measurement of Noise from Small Motors," Dec., 1934 "Measurements of Sound Absorption," Aug., 1934 "Tentative Standards for Sound Level Meters," March, 1936 Journal of the Acoustical Society of America: "Effects of Noise," Jan., 1930 "Results of Noise Surveys," July, 1930 "Practical Methods of Noise Measurement," July, 1930 "Loudness and Intensity Relations," April, 1933 "Scales for Sound Measurements Machinery Noise Reductions," Jan., 1936 "Tentative Standards of Noise Measurement," Bull I Z4.2 and Z Z4.2, 1936 General Elect. Review: "Portable Frequency Analyzer," Aug., 1934 "Noise and Its Measurement," June, 1935 Review of Scientific Instruments: "Integrating Noise Meter," Oct., 1935 Physical Review: "Relative Sensitivity of the Ear," Vol. 20, p. 331, 1922 SUNCO "SOUNDMASTER" Compact portable audio power is the keynote of this 12 watt high fidelity sound reinforcing system, used for interdepartment calling, (such as between sales counter and stockroom) paging, announcing, musical reproduction, etc. Comes complete with crystal microphone, amplifier, 6 all metal tubes, 12 inch dynamic speaker and long cords. 3 individually controlled input channels and extra speaker outlet for 2 way systems. It is designed for floor, wall, ceiling, or truck mounting. For permanent two-way interdepartment talking systems, the No. 181 Amplifier only is used and put in any inconspicuous place. Two No. 184 Microphones are plugged in, and, for distances up to 160 feet, either the baffle, or cabinet type speakers as used in the Soundmaster, are used. In paging systems, one microphone may be mounted at the telephone as illustrated. It is suggested that diagram showing distances be submitted when ordering for permanent installations so that all details may be checked before shipment is made. "Calling Mr. James" - telephone operator's desk, suggested that a rough sketch be submitted when ordering for permanent installations so that all details may be checked before shipment is made. Model 180 Soundmaster, complete with No. 184 Microphone, No. 182 Cabinet Speaker, and No. 181 Amplifier. Weight 32 pounds. Price $67.50. No. 181 - 6 tube 12 watt Audio Amplifier only with 25 foot line cord, 110 V.{VIENNA} 50-60 cycles, 70 watts, size 12-1/2"x6"x7-1/2" H.{Arthur M. Hanbury - Head Complaints}, weight 18 pounds. Price $33.50. No. 182 Cabinet Speaker 12 inch 15 watts, as used in the Soundmaster, 50 foot cord, permanent magnet dynamic type. Weight 16 pounds. Price $16.50. No. 183 Speaker, same as No. 182, but baffle type. Weight 22 pounds. Price $16.00. No. 184 Crystal Microphone Swivel Head. 5 way, Utility, desk, hand, pulpit, suspension, stand. Weight 3 pounds. Price $17.50. In addition to one 8 ohm and two 4 ohm speaker outlets, a 500 ohm output is provided for long line transmission on permanent installations. In this way, one or more speakers may be operated in parallel in different rooms or floors. For permanent installations, the No. 183 Baffle Type Speaker is recommended. While the amplifier output is 12 watts, all speakers furnished are 15 watt capacity to provide for peaks. The large 12 inch speakers provide great air displacement and carrying power but without seeming loud. The Soundmaster represents the finest quality money can buy in workmanship, and material. The three layer plywood case is lined inside and covered outside with grade 3,000 (the best) Keratol black mahogany leatherette. The escutcheon and grille are bright chrome and satin finish. The rear cover is removable as is also the amplifier proper. The No. 183 Baffle Speaker is made of heavy spun aluminum, 17-1/4" dia. sound insulated, has a protective screen over the speaker cone, and is highly directional. | ||