| Description | Date | Identifier | |
| The functionality of an auto switch and its relationship to battery charging and voltage. | 9th Feb 1928 | Box 59 \ 1 Scan259 | |
| Battery charging systems, vibrator regulators, and an auto switch. | 9th Feb 1928 | Box 59 \ 1 Scan260 | |
| Continued report on resistance winding and auto switches for experimental cars. | 1st Feb 1928 | Box 59 \ 1 Scan261 | |
| Wiring diagram for a distribution board with a cut out and auto switch. | 1st Feb 1928 | Box 59 \ 1 Scan262 | |
| Wiring diagram showing winding directions and connections of auto-switch units. | 4th Feb 1928 | Box 59 \ 1 Scan263 | |
| Letter discussing battery performance issues related to temperature and discrepancies in the woodwork of experimental battery containers. | 10th Feb 1928 | Box 59 \ 1 Scan264 | |
| Continued internal memo discussing design constraints and accessibility issues for sheet metal battery boxes. | 13th Feb 1928 | Box 59 \ 1 Scan265 | |
| Requesting experiments on partial temperature compensation for an auto charge control switch using Eureka resistance wire. | 13th Feb 1928 | Box 59 \ 1 Scan266 | |
| Wiring diagram for the connections of an Auto-Charge Control Switch for units A & B. | 9th Feb 1928 | Box 59 \ 1 Scan267 | |
| List detailing various Auto Charge Control Switch Units, their specifications, and locations. | 14th Feb 1928 | Box 59 \ 1 Scan268 | |
| Further points on the auto charge control switch, specifically the addition of an extra coil for protection. | 15th Feb 1928 | Box 59 \ 1 Scan269 | |
| Analysis of the auto switch and dynamo, considering additional protection via a fourth wire and the effects of temperature on the system. | 15th Feb 1928 | Box 59 \ 1 Scan270 | |
| Temperature compensation methods for an auto switch and the use of a series coil. | 15th Feb 1928 | Box 59 \ 1 Scan271 | |
| Improving the temperature compensation of the main shunt coil for an auto switch. | 18th Feb 1928 | Box 59 \ 1 Scan272 | |
| Modification of a battery charge controller to suit a 6-volt American system. | 18th Feb 1928 | Box 59 \ 1 Scan273 | |
| Issues with an automatic charge control device and proposing simpler, driver-operated alternatives. | 22th Feb 1928 | Box 59 \ 1 Scan274 | |
| Auto lighting plants, specifically a permanent magnet instrument and an alternative scheme. | 21th Feb 1928 | Box 59 \ 1 Scan275 | |
| Mathematical analysis of auto switch shunt coil heating. | 21th Feb 1928 | Box 59 \ 1 Scan276 | |
| Page of a technical analysis involving mathematical equations and variables. | 21th Feb 1928 | Box 59 \ 1 Scan277 | |
| Calculating and adjusting the maximum current for a switch based on specific variables. | 22th Feb 1928 | Box 59 \ 1 Scan278 | |
| Request for parts to conduct further tests on a battery charge controller. | 22th Feb 1928 | Box 59 \ 1 Scan279 | |
| Letter from the Springfield, Mass. office to the Derby, England office regarding an auto charge control switch. | 28th Feb 1928 | Box 59 \ 1 Scan280 | |
| Experimental record sheet for an Auto Charge Reducing Switch, tracking mileage, tests, and modifications. | 19th Apr 1926 | Box 59 \ 1 Scan281 | |
| Electrical experimental record sheet for mileage testing of an Auto-switch B (II). | 8th Dec 1928 | Box 59 \ 1 Scan282 | |
| Experimental record sheet for a Dynamo Output Controller. | 19th Apr 1926 | Box 59 \ 1 Scan283 | |
| Alteration instructions for rewinding coils on a U.S.A. Battery Charge Controller. | 15th Mar 1928 | Box 59 \ 1 Scan284 | |
| Particulars of windings for the green lamp scheme and the auto charge control switch for 12-volt systems. | 16th Mar 1928 | Box 59 \ 1 Scan285 | |
| Requesting the modification of a U.S.A. auto switch using a new series Eureka winding. | 29th Feb 1928 | Box 59 \ 1 Scan286 | |
| Improvements to the auto charge control switch and its application to the green lamp scheme. | 2nd Mar 1928 | Box 59 \ 1 Scan287 | |
| Technical discussion on modifying switchboxes and comparing the 'green lamp scheme' against the 'auto switch' for fault indication. | 1st Mar 1928 | Box 59 \ 1 Scan288 | |
| Page 3 of a document discussing the complication of adding an extra terminal and wire for a dynamo's field coil. | 1st Mar 1928 | Box 59 \ 1 Scan289 | |
| Extract from a letter from Mr. Minchin discussing the design of an auto-switch. | 20th Mar 1928 | Box 59 \ 1 Scan290 | |
| Comparison of the 'Auto Charge Control Switch' and the 'Green Lamp Scheme' for vehicle charging systems. | 29th Mar 1928 | Box 59 \ 1 Scan291 | |
| Comparison of the functionality and reliability of an auto switch versus a green lamp unit and a cutout system. | 29th Mar 1928 | Box 59 \ 1 Scan292 | |
| Comparison between a green indicator lamp and an auto switch for the dynamo charging system. | 29th Mar 1928 | Box 59 \ 1 Scan293 | |
| Final arrangement of a 12-volt auto charge control switch and its benefits. | 29th Mar 1928 | Box 59 \ 1 Scan294 | |
| 9000-mile test report on a Phantom chassis concerning its experimental automatic charge control switch and electrical system. | 7th Mar 1928 | Box 59 \ 1 Scan295 | |
| The hold on winding preparations for a U.S.A. auto switch, pending revised specifications. | 30th Mar 1928 | Box 59 \ 1 Scan296 | |
| Complaints and proposed solutions for the Dynamo-Battery System. | 30th Mar 1928 | Box 59 \ 1 Scan297 | |
| Modifications to the charging system and arrangements for the 10,000-mile chassis 12-EX. | 30th Mar 1928 | Box 59 \ 1 Scan298 | |
| Continued discussion on proposed electrical system modifications, including switches and indicating lamps. | 30th Mar 1928 | Box 59 \ 1 Scan299 | |
| Potential fault with the green lamp operating switch in the dynamo-battery circuit and ongoing tests. | 30th Mar 1928 | Box 59 \ 1 Scan300 | |
| Temperature compensation for auto charge control switch units and an associated indicator lamp. | 30th Mar 1928 | Box 59 \ 1 Scan301 | |
| Comparison of the reliability and failure modes of an auto charge control switch versus a green lamp scheme. | 30th Mar 1928 | Box 59 \ 1 Scan302 | |
| Page explaining the indications of a dynamo-battery circuit and warning of potential damage. | 30th Mar 1928 | Box 59 \ 1 Scan303 | |
| Use of parts from an auto charge control switch and requesting a new unit for experiments. | 30th Mar 1928 | Box 59 \ 1 Scan304 | |
| Revised particulars for the windings of a U.S.A. auto switch. | 31th Mar 1928 | Box 59 \ 1 Scan305 | |
| Internal inquiry regarding the delivery date for an Auto Charge Switch for Springfield. | 2nd Apr 1928 | Box 59 \ 1 Scan306 | |
| The winding specifications for an auto switch for the U.S.A. market. | 4th Apr 1928 | Box 59 \ 1 Scan307 | |
| Explaining the delay in the supply of a U.S.A. Auto Switch due to a temperature compensation improvement. | 4th Apr 1928 | Box 59 \ 1 Scan308 | |
| Confirming an arrangement to produce a 12-volt auto charge control switch and modify a U.S.A. switch. | 5th Apr 1928 | Box 59 \ 1 Scan309 | |
| Note regarding a dynamo charging issue with an auto charge control switch. | 5th Apr 1928 | Box 59 \ 1 Scan310 | |
| Table of final windings for the green lamp switch and auto charge control switch. | 14th Apr 1928 | Box 59 \ 1 Scan311 | |
| Confirming the supply of 24 S.W.G. D.C.C. Manganin wire as a replacement for Eureka wire for the auto charge control switch. | 17th Apr 1928 | Box 59 \ 1 Scan312 | |
| Notes regarding the wiring and design of an Auto Switch and Green Lamp Switch. | 17th Apr 1928 | Box 59 \ 1 Scan313 | |
| Failure of a car lighting charge control device and the decision against its implementation. | 18th Apr 1928 | Box 59 \ 1 Scan314 | |
| List of different auto charge control and green lamp switch units, with remarks and locations. | 20th Apr 1928 | Box 59 \ 1 Scan315 | |
| Instruction sheet detailing the electrical resistance and voltage settings for a U.S.A. Auto Switch. | 23th Apr 1928 | Box 59 \ 1 Scan316 | |
| Requesting to put work on an auto charge control switch unit on hold, as per Mr. Royce's request. | 23th Apr 1928 | Box 59 \ 1 Scan317 | |
| Instructions for the removal of the auto charge control switch from chassis 14-EX. | 30th Apr 1928 | Box 59 \ 1 Scan318 | |
| Design and shipment of an auto charge control switch for a 6-volt system. | 30th Apr 1928 | Box 59 \ 1 Scan319 | |
| Specifications for an operating circuit and switch settings under hot and cold conditions. | 30th Apr 1928 | Box 59 \ 1 Scan320 | |
| Installation and adjustment notes for a U.S.A. Auto Switch. | 30th Apr 1928 | Box 59 \ 1 Scan321 | |
| Wiring diagram for the connections of an auto charge control switch. | 5th Apr 1928 | Box 59 \ 1 Scan322 | |
| Attaching a blueprint diagram of connections for the auto charge control switch. | 1st May 1928 | Box 59 \ 1 Scan323 | |
| Electrical experimental record sheet for an Auto-Switch F with brass winding cheeks. | 1st Apr 1928 | Box 59 \ 1 Scan324 | |
| Electrical experimental record sheet for a Dynamo Charge Auto-Switch. | 14th Jun 1928 | Box 59 \ 1 Scan325 | |
| Clarifying the history and halting further development of the auto charge control switch. | 18th Apr 1928 | Box 59 \ 1 Scan326 | |
| Table of approved windings for Green Lamp and Auto Charge Control switches. | 12th Jun 1928 | Box 59 \ 1 Scan327 | |
| List of different types of auto charge control switch units, with remarks and locations. | 9th Jul 1928 | Box 59 \ 1 Scan328 | |
| Road tests of green lamp and auto switch schemes to check the consistency of their settings. | 13th Jul 1928 | Box 59 \ 1 Scan329 | |
| The performance of an auto switch (B), its operating voltages, adjustments, and road test behaviour. | 20th Jul 1928 | Box 59 \ 1 Scan330 | |
| Providing first impressions on the auto-charge switch for model 364-FM. | 20th Jul 1928 | Box 59 \ 1 Scan331 | |
| Cover note for attached notes on the technical development of the Auto Switch. | 9th Sep 1928 | Box 59 \ 1 Scan332 | |
| The technical development of an automatic charge control switch, referencing previous experiments. | 9th Sep 1928 | Box 59 \ 1 Scan333 | |
| The performance and correction of a long-period vibrator regulator and auto-switch system on experimental cars. | 9th Sep 1928 | Box 59 \ 1 Scan334 | |
| Charging switch and vibrator regulator performance and modifications. | 15th Mar 1927 | Box 59 \ 1 Scan335 | |
| Continued discussion on refining a battery charging system, detailing modifications requested by Mr. Royce. | 27th Oct 1927 | Box 59 \ 1 Scan336 | |
| The effects of an auto switch and cutout on a dynamo's field circuit and charging current. | 27th Oct 1927 | Box 59 \ 1 Scan337 | |
| Modifications to a vibrator regulator and auto switch to prevent low-frequency vibration. | 11th Nov 1927 | Box 59 \ 1 Scan338 | |
| The development of an auto switch, detailing differences from the Midgley patents and subsequent improvements. | 9th Dec 1927 | Box 59 \ 1 Scan339 | |
| Page describing the improvement of an operating shunt coil in reducing erratic behaviour caused by voltage variations. | 28th Dec 1928 | Box 59 \ 1 Scan340 | |
| Summary of operating voltages for temperature-compensated auto and green lamp switches. | 28th Dec 1928 | Box 59 \ 1 Scan341 | |
| Test report on a car's electrical switch, detailing its closing voltage under warm and cold conditions. | 28th Dec 1928 | Box 59 \ 1 Scan342 | |
| Wiring diagram for an S.S. Distribution Board, incorporating an Auto Charge Control Switch. | 26th Feb 1929 | Box 59 \ 1 Scan343 | |
| Design of a long type distribution board and its accompanying switchbox. | 25th Mar 1929 | Box 59 \ 1 Scan344 | |
| Requirements for switchboxes to work with a long distribution box and auto switch unit. | 8th May 1929 | Box 59 \ 1 Scan345 | |
| Test results for auto switches and green lamp switches after being run on cars. | 27th Jun 1929 | Box 59 \ 1 Scan346 | |
| The performance and voltage settings of green lamp switches from cars 21-EX and 23-EX. | 27th Jun 1929 | Box 59 \ 1 Scan347 | |
| Summary of operating voltage tests for temperature-compensated auto and green lamp switches. | 27th Jun 1929 | Box 59 \ 1 Scan348 | |
| Test report on the performance and adjustments of a green lamp switch under various conditions and mileages. | 22th Apr 1929 | Box 59 \ 1 Scan349 | |
| Patent specification cover page for an Auto-Switch. | 28th Jun 1929 | Box 59 \ 1 Scan350 | |
| Evolution and arrangement of the S.S. Switchbox positions and functionality. | 8th Jul 1929 | Box 59 \ 1 Scan351 | |
| Experimental auto switch and auto-charge control systems, and their potential installation on chassis 20-EX. | 11th Sep 1929 | Box 59 \ 1 Scan352 | |
| The parts and blueprints for the 40/50 HP chassis auto charge control switch. | 11th Sep 1929 | Box 59 \ 1 Scan353 | |
| Clarifying instructions for the auto charge control switch and associated switchboxes. | 9th Sep 1929 | Box 59 \ 1 Scan354 | |
| Clarifying the process for issuing instructions to the Experimental Department for different sections. | 19th Sep 1929 | Box 59 \ 1 Scan355 | |
| Request to order a 1-lb reel of copper wire for an auto charge control switch. | 28th Oct 1929 | Box 59 \ 1 Scan356 | |
| Note confirming the receipt of three long distribution boards with auto switches, designated J, K & L. | 30th Nov 1929 | Box 59 \ 1 Scan357 | |
| Letter describing a new voltage-operated relay device for controlling the charging rate of car accumulators. | 29th Apr 1930 | Box 59 \ 1 Scan358 | |
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