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).
Examination of a post-war American Bosch ignition coil's construction and windings.
| Identifier | ExFiles\Box 61b\4\ scan0156 | |
| Date | 15th November 1929 | |
| RR 238 (150 BKS.) (DB{Donald Bastow - Suspensions} 461-8-12-24) MP 306975 X4275 ROLLS-ROYCE LTD. INSTRUCTIONS. To E.7.C. Order No. WD{Mr Wood/Mr Whitehead} 90 Customer's No. 15 - 11 - 1929 American Bosch ignition coil Post war type. We have unwound one of these coils to ascertain the construction of the windings and particularly the uniformity of the secondary winding. The following points were noted:- (a) Coil completely sealed in with varnish like magneto armatures. (b) Diameter of enamelled secondary wire .005" which did not vary more than .00025" taken from several measurements during unwinding. (c) Secondary insulation between layers .0025" of varnished paper in one Signed (contd) This Sheet must be filed on completion of the work. | ||