| Description | Date | Identifier | |
| Letter to Mr. Hives regarding coils for the Phantom and enclosing a letter from the American Bosch Magneto Corporation. | 6th Dec 1926 | Box 61b \ 4 scan0105 | |
| Letter from American Bosch Magneto Corporation detailing the resistance of TC-30 and TC-31 ignition coils. | 2nd Dec 1928 | Box 61b \ 4 scan0106 | |
| Letter from the American to the UK branch clarifying the voltage of coils sent for a Phantom double head. | 13th Dec 1928 | Box 61b \ 4 scan0107 | |
| Clarifying a discrepancy with received U.S.A. Bosch ignition system coils. | 22th Dec 1926 | Box 61b \ 4 scan0108 | |
| The dispatch and inspection of Delco-Remy and American Bosch distributor and contact breaker units. | 17th Jan 1927 | Box 61b \ 4 scan0109 | |
| Examination and comparison of Bosch and Delco-Remy contact breakers, focusing on the angular off-set of the breaker pad. | 17th Jan 1927 | Box 61b \ 4 scan0110 | |
| Comparison of battery ignition contact breakers, analyzing point mounting flexibility and contact pressure. | 17th Jan 1927 | Box 61b \ 4 scan0111 | |
| Cross-section diagram and explanation of an umbrella rotor designed for pure air circulation. | 14th May 1927 | Box 61b \ 4 scan0112 | |
| The failure of an American Bosch ignition coil during a 10,000-mile bench test. | 14th May 1927 | Box 61b \ 4 scan0113 | |
| Continuation of an instruction sheet diagnosing an electrical fault in a distributor unit and coil. | 8th Dec 1924 | Box 61b \ 4 scan0114 | |
| Instructions to investigate a sparking noise inside a coil by opening it up for examination. | 8th Nov 1926 | Box 61b \ 4 scan0115 | |
| Comparison testing of ignition contact points from a U.S.A. Bosch distributor. | 18th May 1927 | Box 61b \ 4 scan0116 | |
| Inspection and return of a Bosch ignition coil and a Lucas magneto. | 17th May 1927 | Box 61b \ 4 scan0117 | |
| Despatch of a U.S.A. Bosch ignition coil type TC30 for inspection. | 19th May 1927 | Box 61b \ 4 scan0118 | |
| Inspection report on a failed American Bosch ignition coil type TC30. | 19th May 1927 | Box 61b \ 4 scan0119 | |
| Instructions (page 2) detailing the construction and design of a coil or transformer component. | 8th Dec 1924 | Box 61b \ 4 scan0120 | |
| Instructions on the winding and sealing of a primary and secondary coil using waxed paper and bitumen. | 8th Dec 1924 | Box 61b \ 4 scan0121 | |
| Inspection report on a U.S.A. Bosch Ignition Coil, type TC.30. | 19th May 1927 | Box 61b \ 4 scan0122 | |
| Clarifying a mistake in sending a U.S.A. Bosch coil part. | 20th May 1927 | Box 61b \ 4 scan0123 | |
| Experimental record sheet for an American Bosch ignition coil. | 19th Apr 1926 | Box 61b \ 4 scan0124 | |
| Report comparing the performance of platinum versus tungsten interrupter points, coils, and condensers. | 11th Jun 1926 | Box 61b \ 4 scan0125 | |
| The performance and testing of American Bosch and Delco coils and condensers. | 11th Jun 1926 | Box 61b \ 4 scan0126 | |
| Observations of various ignition contact point samples, comparing platinum and tungsten types. | 31th Dec 1926 | Box 61b \ 4 scan0127 | |
| Analysis of ignition point degradation and performance comparisons across different systems. | 4th Mar 1927 | Box 61b \ 4 scan0128 | |
| Standardization of tungsten points for battery ignition contact breakers. | 4th Mar 1927 | Box 61b \ 4 scan0129 | |
| Continued discussion on ignition system characteristics, focusing on current at break, condenser capacity, and platinum point life. | 4th Mar 1927 | Box 61b \ 4 scan0130 | |
| Sending a Bosch battery ignition head and Lucas magneto, while requesting newer Lucas and Watford models. | 18th Jun 1927 | Box 61b \ 4 scan0131 | |
| Order of precedence for experimental tests on battery ignition contact points. | 14th Jul 1927 | Box 61b \ 4 scan0132 | |
| Continued status update on experimental tests for the Phantom, discussing delays with electrical parts and referencing previous reports. | 5th Jul 1927 | Box 61b \ 4 scan0133 | |
| Experimental comparison of a Delco-Remy lever and point with a U.S.A. Bosch system, and observations on a Robert Bosch ignition set. | 26th Aug 1927 | Box 61b \ 4 scan0134 | |
| Comparison of Delco-Remy and U.S.A. Bosch ignition systems. | 29th Aug 1927 | Box 61b \ 4 scan0135 | |
| Comparing the performance of different ignition contact points and materials. | 31th Aug 1927 | Box 61b \ 4 scan0136 | |
| Standardising tungsten points over platinum, proposing further tests before a decision is made. | 7th Sep 1927 | Box 61b \ 4 scan0137 | |
| Request to fit a new point to a U.S.A. Bosch ignition contact lever. | 7th Sep 1927 | Box 61b \ 4 scan0138 | |
| Requesting the return of a U.S.A. Bosch Ignition contact breaker lever for further experimentation. | 7th Sep 1927 | Box 61b \ 4 scan0139 | |
| The testing and standardization of tungsten ignition contact points. | 9th Sep 1927 | Box 61b \ 4 scan0140 | |
| Report comparing the performance and wear of different contact breaker points. | 6th Oct 1927 | Box 61b \ 4 scan0141 | |
| Follow-up memo requesting the return of a U.S.A. Bosch ignition contact lever for further experiments. | 6th Oct 1927 | Box 61b \ 4 scan0142 | |
| From EFC to RHC chasing the completion of a Bosch contact lever needed for ignition experiments. | 6th Oct 1927 | Box 61b \ 4 scan0143 | |
| Letter regarding the adoption of a new ignition coil without ballast. | 28th Oct 1927 | Box 61b \ 4 scan0144 | |
| The specifications of an American Bosch ignition coil without ballast. | 26th Oct 1927 | Box 61b \ 4 scan0145 | |
| The construction and testing of an ignition coil without ballast, including tabulated results from a six-hour run. | 26th Oct 1927 | Box 61b \ 4 scan0146 | |
| Page from a test report detailing electrical and temperature measurements over time. | 19th Oct 1927 | Box 61b \ 4 scan0147 | |
| Graph of make-ratio speed curves for a U.S.A. Bosch contact breaker at two different gap settings. | 19th Oct 1927 | Box 61b \ 4 scan0148 | |
| Electrical experimental record sheet for an American Bosch ignition distributor. | 19th Apr 1926 | Box 61b \ 4 scan0149 | |
| Inquiry about the advantages of a reversed order of construction for a coil. | 9th Dec 1927 | Box 61b \ 4 scan0150 | |
| Extract comparing two methods of coil construction and their respective advantages. | 19th Dec 1927 | Box 61b \ 4 scan0151 | |
| Summary of the chief advantages of American central H.T. coils. | 7th Jan 1928 | Box 61b \ 4 scan0152 | |
| Instruction note detailing the effects of coronal discharge on electrical insulation and metal components. | 8th Dec 1924 | Box 61b \ 4 scan0153 | |
| Instruction detailing the corrosion of H.T. spring terminals due to nitric acid deposited by ozone. | 8th Dec 1924 | Box 61b \ 4 scan0154 | |
| Proposal to dismantle two American coils (Delco Remy and U.S.A. Bosch) to observe their construction. | 7th Mar 1928 | Box 61b \ 4 scan0155 | |
| Examination of a post-war American Bosch ignition coil's construction and windings. | 15th Nov 1929 | Box 61b \ 4 scan0156 | |
| Instructions and observations on component construction and condition. | 23th May 1931 | Box 61b \ 4 scan0157 | |
| Letter to Bosch Ltd. requesting a catalogue for ignition distributors and coils for 6-cylinder engines. | 23th May 1931 | Box 61b \ 4 scan0158 | |
| Request for up-to-date particulars on Bosch battery ignition distributors and ignition coils for 6-cylinder engines. | 4th Jun 1931 | Box 61b \ 4 scan0159 | |
| Letter from Bosch regarding a request for information on battery ignition distributors and coils for a 6-cylinder engine. | 9th Jun 1931 | Box 61b \ 4 scan0160 | |
| Instructions and specifications for battery ignition systems, including wiring and cable fixing for four and six-cylinder engines. | 1st Aug 1929 | Box 61b \ 4 scan0161 | |
| The function, fitting, and timing of Ignition Coils TA and Ignition Distributors VA 4B and VA 6B. | 4th Jan 1928 | Box 61b \ 4 scan0162 | |
| Letter to Bosch Ltd. requesting clarification on the primary winding of ignition coils for 6-cylinder engines. | 11th Jun 1931 | Box 61b \ 4 scan0163 | |
| Letter from Bosch Limited confirming the primary winding of their coils is situated inside the secondary winding. | 15th Jun 1931 | Box 61b \ 4 scan0164 | |
| Letter to Messrs. Bosch Ltd. requesting an instruction booklet for dynamo and battery ignition units. | 24th Oct 1931 | Box 61b \ 4 scan0165 | |
| Letter from Bosch Limited regarding an instruction book for a Lighting and Starting system, and the unavailability of printed materials for new productions. | 28th Oct 1931 | Box 61b \ 4 scan0166 | |
| Requesting another Bosch ignition coil of a similar type for continued testing. | 3rd Nov 1931 | Box 61b \ 4 scan0167 | |
| Letter from Bosch concerning dynamo and coil ignition units, their wiring, and enclosed blueprints. | 5th Nov 1931 | Box 61b \ 4 scan0168 | |
| Ordering an ignition coil, TE.12/2, from Bosch Limited in Stuttgart. | 17th Nov 1931 | Box 61b \ 4 scan0169 | |
| Price list for a set of Bosch ignition units and a regulator dynamo. | 20th Nov 1931 | Box 61b \ 4 scan0170 | |
| Graph plotting Make Ratio against Breakers Gap for a Bosch Distributor. | 20th Nov 1931 | Box 61b \ 4 scan0171 | |
| Graph of Make Ratio against Speed (RPM) for a Bosch Distributor with varying breaker gap settings. | 5th Sep 1932 | Box 61b \ 4 scan0172 | |
| 500-hour endurance test for a Bosch Distributor V46 S174. | 5th Sep 1932 | Box 61b \ 4 scan0173 | |
| Merits of a battery-only ignition system over a magneto reserve for cars. | 17th Jan 1931 | Box 61b \ 4 scan0174 | |
| Weighing the pros and cons of magneto ignition systems versus double battery ignition systems. | 17th Jan 1931 | Box 61b \ 4 scan0175 | |
| Extract of a memo concerning the ignition system and timing gears for a Japan 3 left-hand chassis. | 20th Jan 1931 | Box 61b \ 4 scan0176 | |
| Substitution of a double battery ignition system for the current battery and magneto arrangement on L.H. chassis. | 21th Jan 1931 | Box 61b \ 4 scan0177 | |
| Engine design choices, including crankshaft balance, ignition, governors, and connecting rod lengths. | 29th Jan 1931 | Box 61b \ 4 scan0178 | |
| Design of a double battery ignition system for the Japan 3 model, including a sketch. | 2nd Feb 1931 | Box 61b \ 4 scan0179 | |
| Example of double battery ignition on a new Stutz 8-cylinder engine. | 5th Feb 1931 | Box 61b \ 4 scan0180 | |
| Double battery ignition for Japan 3 & Phantom II models, with reference to competitor systems. | 7th Feb 1931 | Box 61b \ 4 scan0181 | |
| Unsuccessful investigation into a double battery ignition system for the Japan III and Phantom II models. | 11th Feb 1931 | Box 61b \ 4 scan0182 | |
| Internal memorandum discussing the design and operation of a double battery ignition system. | 7th Feb 1931 | Box 61b \ 4 scan0183 | |
| Proposed ignition scheme with a twelve-point distributor. | 7th Feb 1931 | Box 61b \ 4 scan0184 | |
| Magneto ignition trouble on the 40/50 chassis due to increased compression ratios. | 9th Jun 1932 | Box 61b \ 4 scan0185 | |
| List of six advantages of a dual battery ignition system over a magneto. | 9th Jun 1932 | Box 61b \ 4 scan0186 | |
| Reasons for opposing the replacement of the magneto ignition with a dual battery system on the Phantom chassis. | 10th Jun 1932 | Box 61b \ 4 scan0187 | |
| Extract from a list of suggestions to reduce the cost of the 25 HP chassis, specifically regarding the magneto. | 9th Feb 1931 | Box 61b \ 4 scan0188 | |
| Proposal for a revised wiring scheme for the ignition indicator lamp. | 2nd Feb 1931 | Box 61b \ 4 scan0189 | |
| Technical note on the wiring scheme for the red lamp ignition warning light. | 23th Mar 1932 | Box 61b \ 4 scan0190 | |
| Recommendation to proceed with experimental voltage regulator D.Sch.521 with an alteration to the warning light connection. | 2nd Apr 1932 | Box 61b \ 4 scan0191 | |
| The two methods for operating the red lamp ignition warning light. | 15th Apr 1932 | Box 61b \ 4 scan0192 | |
| Experiments on battery ignition wiring tubes to investigate electrostatic disturbances. | 22th May 1919 | Box 61b \ 4 scan0193 | |
| Analysis of spark behavior and electrostatic effects in high tension wires connected to a coil. | 22th May 1919 | Box 61b \ 4 scan0194 | |
| Investigation into subsidiary sparks and the effects of earthing a tube acting as a condenser. | 22th May 1919 | Box 61b \ 4 scan0195 | |
| Insulated ignition tubes, earthing, and the prevention of subsidiary sparks and potential fire. | 14th Nov 1919 | Box 61b \ 4 scan0196 | |
| Experiments on plain coil ignition and the effect of passing high tension cable through iron and copper tubes. | 14th Nov 1919 | Box 61b \ 4 scan0197 | |
| Test report continuation describing the electrostatic effect of earthing copper and iron tubes on spark length. | 24th Nov 1919 | Box 61b \ 4 scan0198 | |
| Technical note summarizing experiments on high tension distributing wires within a tube and the effects of earthing. | 24th Nov 1919 | Box 61b \ 4 scan0199 | |
| The effects of metallic versus non-metallic tubing on ignition wiring and spark intensity. | 2nd Feb 1925 | Box 61b \ 4 scan0200 | |
| Secret memo discussing the choice of ignition system for the 'V' series, prioritizing reliability over cost. | 2nd Feb 1925 | Box 61b \ 4 scan0201 | |
| Secret memorandum discussing an induction effect causing early ignition and popping in the carburetter for the EAC 'V' Series. | 6th Feb 1925 | Box 61b \ 4 scan0202 | |
| Ignition wiring tubes and the effects of static induction. | 25th Feb 1925 | Box 61b \ 4 scan0203 | |
| Analysis of ignition mis-firing issues, static induction, and the effects of using earthed versus insulated metal tubing for wiring. | 25th Feb 1925 | Box 61b \ 4 scan0204 | |
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