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).
Instructions detailing the electrical characteristics and operational parameters of a horn.
| Identifier | ExFiles\Box 59\3\ Scan059 | |
| Date | 1st December 1924 | |
| RR 238 (150 BKS.) (DB{Donald Bastow - Suspensions} 451-B-12-24) MP 306975 ROLLS-ROYCE LTD. INSTRUCTIONS. To 19 Order No. Customer's No. 2 armature of flat shape, both being laminated. Across the coil is connected either a condenser or a non inductive resistance contained in a metal box. The resistance of the horn between terminals is 7.75 ohms. There is no circuit through when the contacts are open. The horn is capable of operating on 6.0 volts, taking just under 2.0 amperes the pitch frequency being about 700 per sec. As the voltage is increased, the current rises to about 4.5 amperes on 17.0 volts while the intensity of the note increases to an extremely loud tone, the pitch frequency rising Signed (cont-d) This Sheet must be filed on completion of the work. | ||