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).
Letter from Philips Lamps Ltd. concerning the method of connecting a battery filter to suppress interference in a Philips Car-Radio Set.
| Identifier | ExFiles\Box 63\3\ scan0326 | |
| Date | 13th April 1935 | |
| TELEGRAPHIC ADDRESS: "PHILLAMPS", WESTCENT, LONDON. CABLES: PHILLAMPS LONDON. 86153 TELEPHONE: GERRARD No 7777 (PRIVATE EXCHANGE) CODES: UNIVERSAL TRADE, MINERS' & SMELTERS', BENTLEY'S COMPLETE PHRASE. PHILIPS LAMPS LIMITED, PHILIPS HOUSE, 145, CHARING CROSS ROAD LONDON W.C.2 OUR REF. ABC/MCW. YOUR REF. Hs{Lord Ernest Hives - Chair}/Wst.8/MA. DIRECTORS: DR. A.{Mr Adams} F.{Mr Friese} PHILIPS, (DUTCH) L. G.{Mr Griffiths - Chief Accountant / Mr Gnapp} SLOAN J.{Mr Johnson W.M.} P., (BRITISH) C. J.{Mr Johnson W.M.} POWELL, (BRITISH) SIR W. HORWOOD, G.B.E., K.C.B., D.S.O. (BRITISH) MANAGING DIRECTORS: D.{John DeLooze - Company Secretary} C. F.{Mr Friese} VAN EENDENBURG, (DUTCH) A.{Mr Adams} DE JONG, (DUTCH) BRANCHES AT: GLASGOW, MANCHESTER, NEWCASTLE, BIRMINGHAM, BRISTOL, LEEDS, NOTTINGHAM, LIVERPOOL, DUBLIN. RADIO DEPARTMENT Rolls-Royce Ltd., DERBY. WST 13th April, 1935. For the attention of Mr. West. Dear Sirs:- We beg to thank you for your letter of April 12th, dealing with the method of connecting the battery filter of the PHILIPS Car-Radio Set. As the system of suppression used has been specifically designed to dispense with resistive suppressors in the ignition system, it becomes absolutely necessary to take every precaution in order to prevent interference from being picked up by external leads to the set. In order to achieve this end advantage is taken of the fact that the car battery acts as a condensor of high capacity. It is found in practice that in order to reduce the interference to a satisfactorily low level the battery filter must be connected as close to the battery as is physically possible, in order to reduce the length of the leads between the battery and the filter, which would otherwise have interference induced in them by other wires in the electrical equipment. It will be appreciated that at the interference frequencies involved the inductance of only a few feet of wire may be more than sufficient to upset the system of suppression. All quotations and orders are subject to our confirmation and will be executed at the price ruling at the date of delivery. The Company reserve the right to alter prices, discounts, and conditions of sale without notice. All orders accepted are contingent on strikes, fires or other causes beyond our control. Form No. R.12/135-50M-O | ||