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 for fitting condensers and suppressors to reduce electrical interference on various chassis.
| Identifier | ExFiles\Box 63\2\ scan0035 | |
| Date | 23th May 1935 guessed | |
| -2- (c) On certain types of bodies, interference may arise due to the body wiring. Where this is apparent a condenser may be fitted to the bottom terminal of No.6 fuse or the accessory fuses as the necessity arises; always, the bottom terminals of these fuses. (d) On the Bentley chassis a condenser may be required to eliminate noise emanating from the electric petrol pump. A condenser should then be fitted to the bottom terminal of No.3 fuse. A neat slot should be made in the distribution board cover to accomodate this wire and the condenser should be mounted directly beneath the distribution board. (e) Across the two terminals on the windscreen wiper motor. (f) On 40/50 Phantom II chassis from the magneto L.T. junction box terminal on the dashboard to earth. The condensers for the dynamo and screen wiper should be of one microfarad capacity and for the petrol pumps and ignition L.T circuit, .50 micro farad paper dielectric condensers both manufactured by The Telegraph Condenser Co. Ltd., and the connecting wire to the condenser should additionally be insulated with varnished cambric, (Sistoflex) sleeving. The connecting wire must be shortened to the minimum possible without straining the wire. Drawings are available illustrating these condensers and shewing the correct position and fittings for the same. Sparking plug and ignition coil interference. On R.R. cars it will probably be found that no appreciable interference is apparent from the H.T ignition circuit when tuned into a station. No suppressors should be fitted to the sparking plugs or the ignition coil in these cases as the fitting of such interferes with the slow running and idling performance of the engine. On Bentley chassis and certain R.R chassis where H.T ignition noise is intolerable, carbon resistance suppressors may be fitted to each sparking plug and between the coil H.T terminal and distributor. | ||