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 the A.T. Speedometer Co., Ltd. regarding two methods for varying the calibration of new instruments.
| Identifier | ExFiles\Box 165\4\ img304 | |
| Date | 3rd May 1935 | |
| The A.T. SPEEDOMETER Co., Ltd. MAGNETIC SPEEDOMETERS & MOTOR CLOCKS REVOLUTION INDICATORS FOR MOTOR CARS, MOTOR BOATS, AND ENGINES, MILEAGE RECORDERS, ETC. DIRECTORS. W. Henderson-Cleland. A.{Mr Adams} Gordon Smith. H.{Arthur M. Hanbury - Head Complaints} R.{Sir Henry Royce} Buckland. CHRONOS WORKS, NORTH CIRCULAR ROAD, LONDON, N.W.2. ALL COMMUNICATIONS TO BE ADDRESSED TO THE COMPANY. Telephone : GLADSTONE 1136 (4 Lines). Telegrams : Aytespeedo, Crickle, London. YOUR REF. Hs{Lord Ernest Hives - Chair}/Wst.2/MA. PLEASE QUOTE OUR REF. HRB/B. 3rd May, 1935. Messrs. Rolls-Royce Ltd., DERBY. Dear Sirs, Replying to your favour of the 1st inst. and confirming the writer's telephone conversation with Mr. West yesterday afternoon, we beg to state that on the new instruments there are two means of varying the calibration:- One is by demagnetising the magnet down to the revs required. The other is to magnetise the magnet to the full extent, and then vary the calibration by putting a paper washer between the pole piece and the pole piece locking nut. The first way is as simple as with the old type instrument, except that, we suggest, it had better be done always here, although possibly, later on, some means could be arranged whereby, if you wish, you could make these variations at Derby. In the meantime, however, we are prepared to guarantee to you that we will be able to give Per Return Service on any variations of calibration you would be likely to require. Always at your service, We beg to remain, Yours faithfully, For THE A.T. SPEEDOMETER CO. LTD. A.H. Buckland Director. | ||