| Description | Date | Identifier | |
| Instruction sheet regarding the reliability and suitability of untested parts from group A for the RR car. | 24th Jan 1919 | Box 34 \ 1 Scan227 | |
| The systematic investigation of Dubilier made condensers for battery ignition. | 21th Mar 1921 | Box 34 \ 1 Scan228 | |
| Proposal for an additional resonance test on Dubilier made condensers to detect weaknesses. | 21th Mar 1921 | Box 34 \ 1 Scan229 | |
| The testing of condensers, detailing a resonance test and listing serial numbers of units considered acceptable for car use. | 21th Mar 1921 | Box 34 \ 1 Scan230 | |
| Table outlining special tests conducted on twelve Dubilier made condensers for battery ignition. | 21th Mar 1921 | Box 34 \ 1 Scan231 | |
| Results of a series of bench and production tests on three groups of components. | 10th Dec 1930 | Box 34 \ 1 Scan232 | |
| Report page detailing the results of three tests on components from Group D. | 10th Dec 1940 | Box 34 \ 1 Scan233 | |
| Extract from a report on electrical matters, discussing battery ignition systems. | 19th Mar 1921 | Box 34 \ 1 Scan234 | |
| Production cost of battery ignition condensers and the possibility of outsourcing. | 1st Apr 1921 | Box 34 \ 1 Scan235 | |
| Comparison table of various condensers, detailing currents and estimated capacities at different voltages. | 2nd Apr 1921 | Box 34 \ 1 Scan236 | |
| Status report on various condensers in the Experimental Department. | 2nd Apr 1921 | Box 34 \ 1 Scan237 | |
| Unsatisfactory reliability test results of Dubilier condensers compared to in-house versions. | 4th Apr 1921 | Box 34 \ 1 Scan238 | |
| Instruction sheet detailing the test results for Dubilier made condensers. | 7th Apr 1921 | Box 34 \ 1 Scan239 | |
| Query regarding the status of Dubilier make condensers after testing in the Experimental Department. | 7th Apr 1921 | Box 34 \ 1 Scan240 | |
| Letter from Dubilier Condenser Co. Ltd. regarding the testing of chassis condensers. | 12th Apr 1921 | Box 34 \ 1 Scan241 | |
| Unofficial visit to condenser supplier, Dubilier Co., discussing manufacturing processes and potential improvements. | 19th Dec 1920 | Box 34 \ 1 Scan242 | |
| Reliability and testing results of Dubilier and R.R. condensers. | 18th Apr 1921 | Box 34 \ 1 Scan243 | |
| Continued letter urging the Dubilier Company to build condensers in a dustless environment to avoid troubles. | 18th Apr 1921 | Box 34 \ 1 Scan244 | |
| The comparative reliability testing of Dubilier make condensers against the company's own. | 27th Apr 1921 | Box 34 \ 1 Scan245 | |
| The comparative testing of Dubilier and Rolls Royce condensers, with a proposal for their use in production. | 2nd May 1921 | Box 34 \ 1 Scan246 | |
| Request for information on the capacity and construction of a Delco Packard condenser for the Goshawk II engine. | 28th May 1921 | Box 34 \ 1 Scan247 | |
| Feedback from Mr. Royce on the blueprint for a 40/50 HP Battery Ignition Condenser, suggesting alterations. | 4th Jun 1921 | Box 34 \ 1 Scan248 | |
| The performance of two batches of Dubilier Condensers and a request to mark them distinctively. | 8th Jun 1921 | Box 34 \ 1 Scan249 | |
| Confirmation of a telegram from Royce concerning ignition condenser and contact trouble. | 9th Jun 1921 | Box 34 \ 1 Scan250 | |
| Instruction sheet detailing the capacities of two condensers from aero distributors for a Goshawk II engine and a 3EX chassis. | 9th Jun 1921 | Box 34 \ 1 Scan251 | |
| The ignition system components for the 4-EX vehicle after its return from America. | 21th Jun 1921 | Box 34 \ 1 Scan252 | |
| Page questioning the reliability of a condenser's construction. | 10th Dec 1929 | Box 34 \ 1 Scan253 | |
| Preferred insulation material for a condenser on a 40/50 HP chassis. | 23th Jun 1921 | Box 34 \ 1 Scan254 | |
| Request to test four Dubilier Condensers reported to have excessively high capacity. | 25th Jun 1921 | Box 34 \ 1 Scan255 | |
| Instructions regarding the testing and return of faulty Dubilier Condensers. | 23th Jun 1921 | Box 34 \ 1 Scan256 | |
| The testing and return of three out of four Dubilier condensers, one of which failed during a high-voltage resonance test. | 14th Jul 1921 | Box 34 \ 1 Scan257 | |
| Instruction note regarding testing of four Dubilier condensers which have excess capacity. | 4th Jul 1921 | Box 34 \ 1 Scan258 | |
| Instructions detailing a comparison test of different condensers against a standard on a distributor with platinum-iridium points. | 6th Nov 1918 | Box 34 \ 1 Scan259 | |
| Instructions regarding condenser capacity to prevent misfires and splashing at the contact points. | 6th Nov 1918 | Box 34 \ 1 Scan260 | |
| Instruction to test a series of condensers to determine an upper limit and check resonance with an ignition coil. | 6th Nov 1918 | Box 34 \ 1 Scan261 | |
| Instruction sheet detailing the inspection of condensers and their suitability for production. | 6th Nov 1918 | Box 34 \ 1 Scan262 | |
| Electrical characteristics for Remy 6 cylinder, 6-volt ignition coils. | 13th Jul 1921 | Box 34 \ 1 Scan263 | |
| Authorising an increase in the top capacity limit for Dubilier condensers used in battery ignition. | 14th Jul 1921 | Box 34 \ 1 Scan264 | |
| Technical description and comparison of American Bosch and Westinghouse condensers for battery ignition systems. | 1st Dec 1918 | Box 34 \ 1 Scan265 | |
| Extract suggesting experiments to run tungsten contact points with increased condenser capacity. | 16th Aug 1921 | Box 34 \ 1 Scan266 | |
| The initial investigation and measurements of a U.S.A. Bosch battery ignition system. | 5th Sep 1921 | Box 34 \ 1 Scan267 | |
| Continued report on ignition systems, focusing on condenser capacity and the integration of new Bosch battery ignition sets. | 5th Sep 1921 | Box 34 \ 1 Scan268 | |
| Comparing U.S.A. Bosch paper condensers with existing mica condensers for use in battery ignition systems. | 16th Sep 1921 | Box 34 \ 1 Scan269 | |
| Conversion table for various units of electrical capacity. | 27th Sep 1921 | Box 34 \ 1 Scan270 | |
| Technical memo comparing the capacity of different mica condensers for battery ignition systems. | 27th Sep 1921 | Box 34 \ 1 Scan271 | |
| Technical report comparing the capacity, volume, and performance of various ignition condensers. | 27th Sep 1921 | Box 34 \ 1 Scan272 | |
| Continued discussion on condenser capacity for the Goshawk engine, ignition performance, and related component testing. | 27th Sep 1921 | Box 34 \ 1 Scan273 | |
| Instruction on standardising iridio-platinum contact points and increasing condenser capacity to reduce sparking. | 29th Sep 1921 | Box 34 \ 1 Scan274 | |
| The diameter of iridio-platinum contact points and an investigation into increasing condenser capacity. | 10th Dec 1930 | Box 34 \ 1 Scan275 | |
| Unfortunate error in the estimation of the useful volume for the Goshawk condenser. | 25th Oct 1921 | Box 34 \ 1 Scan276 | |
| Continued note comparing the capacity of a Bosch battery ignition system to mica and Goshawk condensers. | 25th Oct 1921 | Box 34 \ 1 Scan277 | |
| Design of an inexpensive condenser for the FE ignition system. | 11th Nov 1921 | Box 34 \ 1 Scan278 | |
| Continued discussion on using tungsten and platinum iridium points for ignition reliability. | 3rd Nov 1921 | Box 34 \ 1 Scan279 | |
| Instructions detailing a test on tungsten contact points with double capacity to suppress sparking. | 7th Nov 1921 | Box 34 \ 1 Scan280 | |
| Instruction sheet detailing a test to reproduce misfiring conditions in American distributors using tungsten points. | 6th Nov 1918 | Box 34 \ 1 Scan281 | |
| Instructions detailing a preliminary test on electrical points. | 6th Nov 1918 | Box 34 \ 1 Scan282 | |
| Investigation into metal transfer, scale formation, and rusting on a distributor roller. | 6th Nov 1918 | Box 34 \ 1 Scan283 | |
| Instructions detailing further tests on contact points using a paper dielectric condenser. | 6th Nov 1918 | Box 34 \ 1 Scan284 | |
| Instructions to test an American ignition set by fitting a mica condenser and observing for contact failure. | 6th Nov 1918 | Box 34 \ 1 Scan285 | |
| Production difficulties and experimental work on condensers, specifically regarding paper insulation. | 16th Nov 1921 | Box 34 \ 1 Scan286 | |
| Technical report discussing the difficulties and comparative analysis of different condenser types and materials. | 10th Dec 1939 | Box 34 \ 1 Scan287 | |
| The specifications and alternatives for a Goshawk ignition condenser, including consulting with Messrs. Dubilier. | 16th Nov 1921 | Box 34 \ 1 Scan288 | |
| Letter from Rolls-Royce of America regarding an enquiry into the breakdown of insulation in paper condensers. | 21th Nov 1921 | Box 34 \ 1 Scan289 | |
| Letter discussing battery ignition condenser tests and comparing test procedures. | 6th Sep 1921 | Box 34 \ 1 Scan290 | |
| Page 2 of a letter from American Bosch Magneto Corporation regarding condenser specifications and testing. | 21th Nov 1921 | Box 34 \ 1 Scan291 | |
| Questioning the purchase of Dubilier condensers and proposing design modifications for increased capacity. | 21th Nov 1921 | Box 34 \ 1 Scan292 | |
| Continued note on achieving a taper shape with square radial ends and rounded corners. | 21th Nov 1921 | Box 34 \ 1 Scan293 | |
| Supply and pricing of condensers for the 40/50 chassis from an outside supplier versus in-house production. | 24th Nov 1921 | Box 34 \ 1 Scan294 | |
| Letter from Metropolitan-Vickers Electrical Co. to Mr. Royce regarding the supply of Mica Splittings for magnetos. | 29th Nov 1921 | Box 34 \ 1 Scan295 | |
| Producing and testing six new condensers using a rediscovered varnished insulating paper for Goshawk Chassis reliability trials. | 2nd Dec 1921 | Box 34 \ 1 Scan296 | |
| Cover letter forwarding a communication from 'OY' regarding condensers. | 6th Dec 1921 | Box 34 \ 1 Scan297 | |
| Design and capacity of a new condenser for the 40/50 model's standard battery ignition. | 8th Dec 1921 | Box 34 \ 1 Scan298 | |
| Improvements for the Goshawk Condenser, including material changes and capacity adjustments. | 9th Dec 1921 | Box 34 \ 1 Scan299 | |
| Technical discussion on the materials and design of electrodes and dielectrics, with a small sketch. | 12th Dec 1921 | Box 34 \ 1 Scan300 | |
| Conversion table for various units of electrical capacity. | 12th Dec 1921 | Box 34 \ 1 Scan301 | |
| Condenser capacity for the battery ignition system of 40/50 & Goshawk engines. | 29th Dec 1921 | Box 34 \ 1 Scan302 | |
| Spark generation and condenser discharge in the Goshawk ignition system. | 18th Jan 1922 | Box 34 \ 1 Scan303 | |
| The provision of two standard 40/50 condensers with paper dielectrics for trial on experimental cars. | 18th Jan 1922 | Box 34 \ 1 Scan304 | |
| Condenser capacity tests for the Goshawk engine ignition system, noting misfiring speeds at various voltages. | 16th Mar 1922 | Box 34 \ 1 Scan305 | |
| Investigation into the performance of U.S.A. Bosch battery ignition condensers, noting capacity drop and leakage when heated. | 5th Aug 1921 | Box 34 \ 1 Scan306 | |
| Requesting to find a supplier for a portable condenser testing set. | 3rd Aug 1922 | Box 34 \ 1 Scan307 | |
| Letter from a scientific laboratory supplier redirecting an enquiry for galvanometers. | 5th Aug 1922 | Box 34 \ 1 Scan308 | |
| Letter from The General Electric Co. Ltd. acknowledging receipt of an enquiry for a Portable Testing Set for Condensers. | 9th Aug 1922 | Box 34 \ 1 Scan309 | |
| Letter from W.G. Pye & Co. proposing an alternative design for a testing instrument for Rolls-Royce. | 10th Aug 1922 | Box 34 \ 1 Scan310 | |
| Circuit diagram for a condenser testing bridge using an induction coil and telephone receiver. | 11th Aug 1922 | Box 34 \ 1 Scan311 | |
| Quotation and technical response regarding a portable testing set for condensers. | 11th Aug 1922 | Box 34 \ 1 Scan312 | |
| Quotation for a portable capacity test set from The Cambridge and Paul Instrument Company. | 11th Aug 1922 | Box 34 \ 1 Scan313 | |
| Letter from John J. Griffin & Sons, Ltd. regarding the testing of condensers. | 14th Aug 1922 | Box 34 \ 1 Scan314 | |
| Quotation from The General Electric Co. Ltd. for a High Sensitivity Ballistic Galvanometer. | 22th Aug 1922 | Box 34 \ 1 Scan315 | |
| Continuation of a letter from The General Electric Co., Ltd. regarding instrument specifications and delivery. | 22th Aug 1922 | Box 34 \ 1 Scan316 | |
| Illustration of a precision physical measurement instrument, possibly a type of galvanometer or magnetometer. | 22th Aug 1922 | Box 34 \ 1 Scan317 | |
| From Nalder Bros & Thompson Ltd declining a request. | 22th Aug 1922 | Box 34 \ 1 Scan318 | |
| And comparing options for a condenser testing instrument from various suppliers. | 12th Sep 1922 | Box 34 \ 1 Scan319 | |
| Copy of a letter from Gambrell Bros. Limited regarding a sample electrical testing instrument. | 24th Aug 1922 | Box 34 \ 1 Scan320 | |
| Offers from various suppliers for a portable condenser testing set. | 13th Sep 1922 | Box 34 \ 1 Scan321 | |
| Trial of the sample 'Onward' Galvanometer which was found unsuitable for the portable condenser testing set. | 21th Sep 1922 | Box 34 \ 1 Scan322 | |
| Despatch of a Portable Condenser Testing Set and an 'Onward' Galvanometer. | 22th Sep 1922 | Box 34 \ 1 Scan323 | |
| Request for an order to purchase various electrical components to build a portable condenser testing set. | 23th Nov 1922 | Box 34 \ 1 Scan324 | |
| Failure of battery ignition on 40/50 chassis due to premature burnout of platinum points, and a proposed fix using a different condenser. | 7th Jun 1923 | Box 34 \ 1 Scan325 | |
| Calling for a meeting to discuss differing opinions on the value of various condensers for 40/50 & 20HP models. | 12th Jun 1923 | Box 34 \ 1 Scan326 | |
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