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).
Test results and analysis of experimental work on trembler coils, including a table of their electrical properties.
| Identifier | Morton\M3.3\ img025 | |
| Date | 20th February 1920 | |
| Contd. Ck{Mr Clark}2/T24, 2, 20. The results of these tests were rather instructive to us, as we had not so far done any experimental work on trembler coils. The particulars of the coils experimented on are as follows :- Coil No. Voltage. Approx. primary resis: (Ohms). Approx. secondary resis: (ohms). Approx. primary inductance (henries). Approx. Condenser capacity (mf). 6384 4 .43 4660 .0053 .72 6162 6 1.00 5970 .0097 .49 6163 6 1.00 6365 .0103 .49 No.0. 12 3.5 6595 .042 Unreadably small. Coil No.6162 is fitted with a standard trembler. Coil No.6163 is fitted with a trembler of the same type as the coil now sent to you, otherwise these two coils, as you will see from the figures, are practically identical. The 12 volt coil No.0 is fitted with a standard trembler. Coil No.6162, when properly adjusted for minimum current which is 1.25 amps., gave very good vacuum tube brilliancy and spark length results, but the regularity of the breaks, as shown on the rotating vacuum tube, was not perfectly constant, as was shown by the jumping about of the rotating vacuum tube figures. As the platinum screw is screwed down from the extreme "out" position, the first effect is that the current is large, but conditions Contd. | ||