| Description | Date | Identifier | |
| Test report on a standard ignition coil on engine 10 EX, detailing misfires during pick-up at high temperatures. | 18th Sep 1928 | Box 69 \ 1 scan0141 | |
| Instruction sheet detailing ignition system adjustments and performance tests, noting issues with misfires during acceleration. | 1st Dec 1924 | Box 69 \ 1 scan0142 | |
| Test report comparing the performance of a standard ignition coil against a P.W.P. coil after prolonged heating. | 8th Dec 1924 | Box 69 \ 1 scan0143 | |
| Requesting experimental modifications for a 20,000 turn ignition coil and a new type of ballast resistance. | 19th Sep 1928 | Box 69 \ 1 scan0144 | |
| High-temperature bench test results for a paraffin-waxed paper coil. | 19th Sep 1928 | Box 69 \ 1 scan0145 | |
| Test report on a distributor with 5.5mm third point spark gaps in air. | 8th Dec 1924 | Box 69 \ 1 scan0146 | |
| Instructions detailing adjustments to a contact breaker and ballast, and observing performance at various RPMs. | 8th Dec 1924 | Box 69 \ 1 scan0147 | |
| Instructions memo confirming satisfactory coil operation with current settings. | 8th Dec 1924 | Box 69 \ 1 scan0148 | |
| Road test procedure for experimental ignition coils. | 22th Sep 1928 | Box 69 \ 1 scan0149 | |
| Two faulty ignition coils with partially burnt primaries sent for inspection. | 28th Sep 1928 | Box 69 \ 1 scan0150 | |
| Bench tests and leakage tests conducted on paraffin wax filled coils. | 29th Sep 1928 | Box 69 \ 1 scan0151 | |
| The performance and electrical properties of paraffin wax filled coils. | 1st Oct 1928 | Box 69 \ 1 scan0152 | |
| Testing and construction of a 20,000 turn ignition coil using paraffin wax paper insulation. | 1st Oct 1928 | Box 69 \ 1 scan0153 | |
| Use of paraffin wax for insulating ignition coils. | 11th Oct 1928 | Box 69 \ 1 scan0154 | |
| Bench tests conducted on paraffin wax filled coils to assess their performance and temperature effects. | 29th Sep 1928 | Box 69 \ 1 scan0155 | |
| Conclusion on the lack of advantage of using paraffin wax-filled coils over standard ones. | 3rd Oct 1928 | Box 69 \ 1 scan0156 | |
| Failures of the Phantom ignition coil due to overheating and a proposal to reposition it. | 3rd Oct 1928 | Box 69 \ 1 scan0157 | |
| Page outlining the procedure for measuring coil temperature increase by resistance and conducting insulation tests. | 9th Oct 1928 | Box 69 \ 1 scan0158 | |
| Ignition coil test procedure on a Phantom model. | 9th Oct 1928 | Box 69 \ 1 scan0159 | |
| Instructions detailing tests on ignition coil temperature for 20HP and 40/50HP chassis. | 17th Oct 1928 | Box 69 \ 1 scan0160 | |
| Instructions for tests on coil heating and resistance carried out on various chassis. | 8th Dec 1924 | Box 69 \ 1 scan0161 | |
| Instructions for testing ignition coil temperatures under different engine running conditions, including magneto and battery ignition. | 8th Dec 1924 | Box 69 \ 1 scan0162 | |
| Test results for engine coil temperatures under different ignition conditions. | 1st Dec 1924 | Box 69 \ 1 scan0163 | |
| Instructions and test results for coil temperature after running on battery ignition and magnetos. | 8th Dec 1924 | Box 69 \ 1 scan0164 | |
| Instructions and test results for ignition coil temperature readings. | 8th Dec 1924 | Box 69 \ 1 scan0165 | |
| Coil temperature test results for a 40/50 HP chassis 98NK after road running on different ignition systems. | 8th Dec 1924 | Box 69 \ 1 scan0166 | |
| Continuation test instruction sheet (page 8) detailing coil winding temperatures after a run on battery ignition. | 8th Dec 1924 | Box 69 \ 1 scan0167 | |
| Instruction sheet detailing maximum ignition coil temperatures and charring conditions. | 1st Dec 1924 | Box 69 \ 1 scan0168 | |
| Comparing the heating of the Phantom ignition coil in different positions on 20 HP and 40/50 HP chassis. | 2nd Nov 1928 | Box 69 \ 1 scan0169 | |
| Temperature tests conducted on ignition coils for 20 HP and 40/50 HP chassis. | 2nd Nov 1928 | Box 69 \ 1 scan0170 | |
| Internal memorandum requesting the production of a new Ignition Coil and Ballast Resistance to updated drawings for testing. | 7th Nov 1928 | Box 69 \ 1 scan0171 | |
| Electrical experimental record sheet logging the testing and failure of a standard coil with waxed paper insulation. | 5th Sep 1928 | Box 69 \ 1 scan0172 | |
| Electrical experimental record sheet for a finer primary coil with specially built up primary winding. | 28th Dec 1928 | Box 69 \ 1 scan0173 | |
| Ignition coil failures and proposing experimental modifications to the windings to prevent electrical breakdown. | 31th Dec 1928 | Box 69 \ 1 scan0174 | |
| Ignition coil failures during bench tests, identifying the cause as insulation breakdown. | 29th Dec 1928 | Box 69 \ 1 scan0175 | |
| Requesting an ignition coil core be rewound to a standard order. | 1st Jan 1929 | Box 69 \ 1 scan0176 | |
| Improvements to the winding of ignition coils. | 7th Jan 1929 | Box 69 \ 1 scan0177 | |
| Instructions and results for a coil temperature test with a ballast resistance. | 15th Jan 1929 | Box 69 \ 1 scan0178 | |
| Coil temperature increases using different ballast resistances and the potential detrimental effects. | 17th Oct 1928 | Box 69 \ 1 scan0179 | |
| Urgently requesting an Ignition Coil, part number D.71650. | 15th Jan 1929 | Box 69 \ 1 scan0180 | |
| Inquiring about the completion status of an ignition coil test. | 30th Jan 1929 | Box 69 \ 1 scan0181 | |
| To Mr. Brock requesting the winding of a coil to specification D.71919. | 2nd Feb 1929 | Box 69 \ 1 scan0182 | |
| Table of resistance and inductance particulars for various ignition coils at atmospheric temperature. | 8th Feb 1929 | Box 69 \ 1 scan0183 | |
| Instruction note regarding the supply of an Ignition Coil to the Experimental Department. | 8th Feb 1929 | Box 69 \ 1 scan0184 | |
| Test log for a coil with a specially built-up primary winding. | 11th Feb 1929 | Box 69 \ 1 scan0185 | |
| Production test procedures for an ignition coil. | 18th Feb 1929 | Box 69 \ 1 scan0186 | |
| Test procedures for an electrical distributor and contact breaker. | 19th Feb 1929 | Box 69 \ 1 scan0187 | |
| Production test for an ignition coil amended for a new ballast resistance. | 19th Feb 1929 | Box 69 \ 1 scan0188 | |
| Testing status of paraffin waxed paper ignition coils. | 26th Mar 1929 | Box 69 \ 1 scan0189 | |
| Requesting the production of an experimental ignition coil with 20,000 turns instead of the standard 18,000. | 4th Apr 1929 | Box 69 \ 1 scan0190 | |
| Instruction sheet detailing road test results for a paraffin waxed paper coil. | 6th Apr 1929 | Box 69 \ 1 scan0191 | |
| Instruction sheet detailing the comparison of a coil against a standard and the planned investigation into paraffin wax leakage at high temperatures. | 12th Apr 1929 | Box 69 \ 1 scan0192 | |
| Coil XQP15, which has been modified with 2,000 extra turns on its secondary winding. | 12th Apr 1929 | Box 69 \ 1 scan0193 | |
| Procedure for testing and comparing experimental coils. | 23th Apr 1929 | Box 69 \ 1 scan0194 | |
| Continued test procedure for an electrical coil, outlining steps for performance evaluation under various conditions. | 23th Apr 1929 | Box 69 \ 1 scan0195 | |
| Continuation page detailing endurance testing procedures for a coil component. | 24th Apr 1929 | Box 69 \ 1 scan0196 | |
| Telegram reporting the failure of an ignition coil and its replacement with a spare. | 24th Apr 1929 | Box 69 \ 1 scan0197 | |
| Experimental ignition coil test programme. | 25th Apr 1929 | Box 69 \ 1 scan0198 | |
| Request to supply the Experimental Department with two experimental ignition coils. | 10th May 1929 | Box 69 \ 1 scan0199 | |
| Extract from a report on a faulty ignition coil that was causing mis-fires. | 30th May 1929 | Box 69 \ 1 scan0200 | |
| The fitting of an experimental ignition coil to a specific chassis. | 7th May 1929 | Box 69 \ 1 scan0201 | |
| Testing of a new coil design with a Bakelite spool and altered insulation. | 8th May 1929 | Box 69 \ 1 scan0202 | |
| Internal request to change a PWP coil on chassis 17-G4 for a standard ignition coil. | 17th May 1929 | Box 69 \ 1 scan0203 | |
| Arranging for ignition coil road tests to be conducted by Mr. West. | 18th May 1929 | Box 69 \ 1 scan0204 | |
| Instruction note regarding the dispatch of four ignition coils to Drawing D.71919. | 24th May 1929 | Box 69 \ 1 scan0205 | |
| Faulty ignition coil from car 22-EX in France, detailing misfires and its return to Derby for investigation. | 29th May 1929 | Box 69 \ 1 scan0206 | |
| Investigation into the failure of an ignition coil from a test car in France. | 8th May 1929 | Box 69 \ 1 scan0207 | |
| Instruction sheet detailing a fault with a secondary winding and the proposed remedial actions. | 8th Dec 1924 | Box 69 \ 1 scan0208 | |
| Instruction to fit three ignition coils with 20,000 secondary turns to specific chassis. | 3rd Jun 1929 | Box 69 \ 1 scan0209 | |
| Instruction sheet detailing part numbers for coils related to a specific drawing number and order completion. | 4th Jun 1929 | Box 69 \ 1 scan0210 | |
| Request to test, modify, and fit two paraffin waxed paper condensers to specific chassis. | 18th Jun 1929 | Box 69 \ 1 scan0211 | |
| Request for two paraffin waxed paper condensers for bench tests, following previous tests on an experimental chassis. | 8th Jun 1929 | Box 69 \ 1 scan0212 | |
| Road test report for ignition coil No. LS1. | 20th Jun 1929 | Box 69 \ 1 scan0213 | |
| Continuation of a test report on engine performance and ignition systems at varying temperatures and conditions. | 17th Jul 1929 | Box 69 \ 1 scan0214 | |
| Allowing Mr. Minchin to retain a coil and ballast resistance for experimental reporting. | 26th Jun 1929 | Box 69 \ 1 scan0215 | |
| Request to fit an experimental 20,000 turn secondary ignition coil to chassis 12-G4. | 8th Jul 1929 | Box 69 \ 1 scan0216 | |
| Cover memo regarding failures of ignition coil secondaries, referencing an attached report. | 9th Jul 1929 | Box 69 \ 1 scan0217 | |
| Instruction sheet detailing the fault finding on a returned coil by unwinding it. | 9th Jul 1929 | Box 69 \ 1 scan0218 | |
| Investigation into a faulty coil, identifying the cause as a poor and irregular foundation for the secondary winding. | 8th Dec 1924 | Box 69 \ 1 scan0219 | |
| Instructions on remedying irregular wire spacing and stress on a coil. | 8th Dec 1924 | Box 69 \ 1 scan0220 | |
| Failures and testing of new ignition coil designs. | 11th Jul 1929 | Box 69 \ 1 scan0221 | |
| Electrical experimental record sheet for a coil with specially built up windings. | 15th Jul 1929 | Box 69 \ 1 scan0222 | |
| Requesting confirmation on details for the standard ignition coil. | 8th Jul 1929 | Box 69 \ 1 scan0223 | |
| Particulars of construction for the present standard ignition coil. | 18th Jul 1929 | Box 69 \ 1 scan0224 | |
| Coil and Ballast Resistance for chassis GFN-8, requesting the units be sent to settle the job. | 5th Sep 1929 | Box 69 \ 1 scan0225 | |
| Specification table for various coil primary windings. | 25th Sep 1929 | Box 69 \ 1 scan0226 | |
| Test schedule report for various experimental coils, detailing electrical and thermal performance. | 23th Apr 1929 | Box 69 \ 1 scan0227 | |
| Burnt-out ignition coil, requesting investigation and repair. | 4th Oct 1929 | Box 69 \ 1 scan0228 | |
| Electrical failures and subsequent repairs on Chassis No. 101-UF. | 7th Oct 1929 | Box 69 \ 1 scan0229 | |
| Inquiring about the highest recorded temperature under a car bonnet in relation to ignition coils. | 8th Oct 1929 | Box 69 \ 1 scan0230 | |
| Failure and burnout of an ignition coil on chassis 101-UF. | 8th Oct 1929 | Box 69 \ 1 scan0231 | |
| Instruction sheet detailing coil temperature tests under abnormal conditions. | 10th Oct 1929 | Box 69 \ 1 scan0232 | |
| Continuation sheet of a coil test report, detailing the conditions and procedure for Test 2. | 8th Dec 1924 | Box 69 \ 1 scan0233 | |
| Test report on the temperature of a coil and the condition of its primary insulation after testing. | 12th Dec 1924 | Box 69 \ 1 scan0234 | |
| Investigation into a failed ignition coil on chassis 101-UF. | 10th Oct 1929 | Box 69 \ 1 scan0235 | |
| Typed memorandum discussing the use of an auto switch control system as a remedy for a recurring danger. | 14th Oct 1929 | Box 69 \ 1 scan0236 | |
| Experiments to determine the charring temperature of cotton-covered ignition coil wire. | 14th Oct 1929 | Box 69 \ 1 scan0237 | |
| Instructions detailing the discoloration of a wire at various temperatures, from 200°C up to 320°C. | 8th Dec 1924 | Box 69 \ 1 scan0238 | |
| Ignition coil temperature tests and the charring effect on the primary winding. | 16th Oct 1929 | Box 69 \ 1 scan0239 | |
| The testing of a coil and the charring temperature of its cotton insulation. | 6th Oct 1929 | Box 69 \ 1 scan0240 | |
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