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).
Modifications required for coil D.75672 following experimental testing.
| Identifier | ExFiles\Box 164\5\ img280 | |
| Date | 11th May 1937 | |
| 6017 By/RD. from Rm{William Robotham - Chief Engineer}/Wst. c. B. Rm{William Robotham - Chief Engineer}/Wst.6/AP.11.5.37 COIL TO D.75672 As a result of experimental testing we have found the following modifications necessary:- (a) Flexible wire connections to all terminals the primary ends to be brought up the centre of the terminal screw and soldered at the top. (b) Large Thackery spring washer at each end of the iron core to prevent movement due to vibration. (c) 6 layers of paper instead of four between top and bottom layers of secondary winding and four layers between the next layer at each end following on through the winding with the usual insulation. This is for the 15000 turn Secondary wound with 42 SWG. wire. Will you kindly instruct these modifications as soon as possible as it is quite likely this coil will be wanted for 25/30 and Bentley production very shortly. Rm{William Robotham - Chief Engineer}/Wst. | ||