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 to the Cambridge Instrument Co. with queries about a Chronograph's performance.
| Identifier | ExFiles\Box 138\2\ scan0027 | |
| Date | 22th May 1924 | |
| X4630 Hs{Lord Ernest Hives - Chair}/Rml/LG. 22nd. May 1924. The Cambridge Instru: Co., Cambridge, England. Dear Sirs, Thank you for your letter of the 19th.inst. We are now in receipt of the Chronograph which is working very satisfactorily. There are, however, one or two points about which we should like further information. (a) The coils of the electro magnets seem to get unduly hot in the 12-volt circuit. The resistance on the board appears to be in series with these coils - can we reduce their temperature by adjusting this resistance? (b) The adjustments of the gaps between the magnetic cores and the pen carriers did not appear to be locked up in any case, nor were any two gaps the same. What gap do you recommend as being the most satisfactory for general work? We do not wish to introduce any lag by over-increasing the amplitude of the pen movement. (c) We find one of the windings of the electro magnets to be loose upon the core - do you consider this to be due to over-heating? (d) We hope, amongst other things, to use this instrument in cars decelerating as much as 20 ft./sec² - is the time recording element likely to be affected by these conditions? Thanking you in anticipation. Yours faithfully. | ||