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).
Table detailing the location and status of various Watford Aero Magnetos.
| Identifier | ExFiles\Box 43\4\ Scan109 | |
| Date | 12th January 1928 | |
| E.F.C. X4021 12.1.28 PRESENT LOCATION OF WATFORD AERO MAGNETOS. (15° range) Characteristics. Magneto No. Location. Remarks. Uptodate. { 83119.S. { Lab. } HEW. altering range(struck through) To 20°. { 83120.P. { Lab. Axial distributors. { 83132.P. { Lab. { 83133.S. { Lab. { 83134.P. { Lab. { 83135.S. { Lab. Bakelite radial { 83136.P. { Lab. } Failed, points burnt away. distributors. { 83137.S. { Lab. EFC. | ||