| Description | Date | Identifier | |
| Review of different battery types, comparing costs, cold starting performance, and longevity, with a recommendation for standardization. | 22th Apr 1936 | Box 58 \ 4 Scan258 | |
| Recommendation to switch to new Exide batteries for production models while continuing to test experimental Dagenite batteries. | 22th Apr 1936 | Box 58 \ 4 Scan259 | |
| Request for a list and dimensions of negative and positive battery plates from Peto & Radford Co. Ltd. | 23th Apr 1936 | Box 58 \ 4 Scan260 | |
| Request to Chloride Electrical Storage Co. Ltd. for a list of battery plate dimensions and thicknesses. | 23th Apr 1936 | Box 58 \ 4 Scan261 | |
| Letter from accumulator manufacturer Peto & Radford providing a schedule of battery plate sizes. | 24th Apr 1936 | Box 58 \ 4 Scan262 | |
| Schedule detailing the dimensions and types of battery plates. | 24th Apr 1936 | Box 58 \ 4 Scan263 | |
| Letter from The Chloride Electrical Storage Co. Ltd. providing dimensions for various battery plates. | 25th Apr 1936 | Box 58 \ 4 Scan264 | |
| Letter from Exide Batteries regarding the availability and samples of battery plates. | 25th Apr 1936 | Box 58 \ 4 Scan265 | |
| Decision to use thin plate batteries on the Phantom III, 25/30, and Bentley models. | 25th Apr 1936 | Box 58 \ 4 Scan266 | |
| Confirming the use of thin plate batteries on the Phantom III model, while postponing the change for the 25/30 and Bentley models. | 27th Apr 1936 | Box 58 \ 4 Scan267 | |
| Letter from an accumulator manufacturer concerning the examination of a faulty battery. | 27th Apr 1936 | Box 58 \ 4 Scan268 | |
| Letter to Peto & Radford Ltd. regarding a returned battery that did not give its rated capacity. | 28th Apr 1936 | Box 58 \ 4 Scan269 | |
| Laboratory test report on a returned 6-HZD9-S battery. | 28th Apr 1936 | Box 58 \ 4 Scan270 | |
| Letter from PETO & RADFORD concerning the apparent failure of separators and the arrangement of further capacity tests. | 29th Apr 1936 | Box 58 \ 4 Scan271 | |
| Letter to Messrs. Peto & Radford Co. Ltd. regarding a battery capacity test conclusion. | 29th Apr 1936 | Box 58 \ 4 Scan272 | |
| Order be passed to Peto & Radford Ltd. for various accumulators. | 29th Apr 1936 | Box 58 \ 4 Scan273 | |
| Life test schedule for thin plate Exide XC and Dagenite HZ batteries. | 29th Apr 1936 | Box 58 \ 4 Scan274 | |
| Use of thin plate batteries for the Phantom III chassis and experimental testing for Bentley models. | 29th Apr 1936 | Box 58 \ 4 Scan275 | |
| Requesting details on Exide batteries for the Phantom III chassis and an update on P & R battery approval. | 5th May 1936 | Box 58 \ 4 Scan276 | |
| The Exide battery for the Phantom III chassis and the testing of the P.& R. battery. | 9th May 1936 | Box 58 \ 4 Scan277 | |
| Letter from accumulator manufacturer Peto & Radford discussing and comparing their battery design with a competitor's for the Phantom III. | 11th May 1936 | Box 58 \ 4 Scan278 | |
| Letter from Peto & Radford to H.E. West regarding a decision on a thin plate lighter weight Bentley battery. | 11th May 1936 | Box 58 \ 4 Scan279 | |
| Providing the manufacturer's reference number for the Phantom III model's Exide battery. | 12th May 1936 | Box 58 \ 4 Scan280 | |
| Letter to Mr. Minchin of Peto & Radford Ltd. regarding car and Bentley battery tests and supply. | 13th May 1936 | Box 58 \ 4 Scan281 | |
| Letter from an accumulator manufacturer regarding the supply and testing of different battery plates. | 14th May 1936 | Box 58 \ 4 Scan282 | |
| Letter from accumulator manufacturers Peto & Radford arranging a visit to Derby. | 18th May 1936 | Box 58 \ 4 Scan283 | |
| Letter to Mr. Minchin confirming an appointment for the 28th of the month. | 20th May 1936 | Box 58 \ 4 Scan284 | |
| Letter from accumulator manufacturer Peto & Radford regarding a change of arrangements for a visit. | 20th May 1936 | Box 58 \ 4 Scan285 | |
| Damage to batteries caused by the securing method in the chassis and proposing a solution. | 20th Apr 1936 | Box 58 \ 4 Scan286 | |
| Letter from Peto & Radford regarding the return of a 6-HZD9-S battery after tests were completed. | 21th May 1936 | Box 58 \ 4 Scan287 | |
| Urgent battery order for a Bentley Chassis. | 26th May 1936 | Box 58 \ 4 Scan288 | |
| Letter from accumulator manufacturers Peto & Radford confirming a meeting. | 26th May 1936 | Box 58 \ 4 Scan289 | |
| Order for a standard Bentley Exide 12 volt battery. | 29th Apr 1936 | Box 58 \ 4 Scan290 | |
| Order for a Peto & Radford battery for experimental testing on a Phantom III. | 30th May 1936 | Box 58 \ 4 Scan291 | |
| Recommending to revert to sharing battery orders for the Phantom III chassis between two firms. | 30th Apr 1936 | Box 58 \ 4 Scan292 | |
| Ordering of standard batteries for Bentley chassis, as the standardization for thinner plate batteries is not yet ready. | 30th May 1936 | Box 58 \ 4 Scan293 | |
| Letter from Dagenite Accumulators regarding battery testing and specifications for the Phantom III. | 2nd Jun 1936 | Box 58 \ 4 Scan294 | |
| Letter from Peto & Radford discussing battery testing, specifications, and proposals for various car models. | 8th Jun 1936 | Box 58 \ 4 Scan295 | |
| Letter from accumulator manufacturers Peto & Radford regarding the battery title for the Phantom III. | 8th Jun 1936 | Box 58 \ 4 Scan296 | |
| Letter concerning two large car batteries loaned by the Bentley Service Depot for the R.A.F. and S.B.A.C. shows that have gone missing. | 11th Jul 1936 | Box 58 \ 4 Scan297 | |
| Confirming the return of loaned batteries for the S.B.A.C. Show. | 4th Aug 1936 | Box 58 \ 4 Scan298 | |
| Advantages of reversing polarity to a positive earth system on R.R. and Bentley cars. | 19th Aug 1936 | Box 58 \ 4 Scan299 | |
| Letter from The Concordia Electric Wire Co. Ltd. promoting their new 'Concord Herculacker' cellulose lacquer cables. | 4th Feb 1930 | Box 59 \ 1 Scan001 | |
| Requesting a revised list of L.T. cables for the Phantom chassis and proposing an experimental set of wires. | 24th Feb 1930 | Box 59 \ 1 Scan002 | |
| Requirements for low tension cable for the Phantom II chassis and ordering wire for experimental purposes. | 5th Mar 1930 | Box 59 \ 1 Scan003 | |
| Specification table for low tension wire required per Phantom II chassis. | 14th May 1930 | Box 59 \ 1 Scan004 | |
| Proposed changes to the Phantom II Chassis L.T. (Low Tension) wiring. | 10th Mar 1930 | Box 59 \ 1 Scan005 | |
| Conductor sizes and the potential use of experimental cellulose lacquered L.T. wire for the 40/50 HP chassis. | 11th Mar 1930 | Box 59 \ 1 Scan006 | |
| Request to obtain a tin of cellulose lacquer to apply to the ends of cut cable insulation to prevent fraying. | 20th Sep 1930 | Box 59 \ 1 Scan007 | |
| Clarifying the requirement for clear cellulose varnish for L.T. cables, as the wrong black varnish had been supplied. | 30th Sep 1930 | Box 59 \ 1 Scan008 | |
| Correct application of black cable varnish with the Macintosh Cable Co. Ltd. | 3rd Oct 1930 | Box 59 \ 1 Scan009 | |
| Incorrect black varnish received from Macintosh Cable Co., and requiring a clear cellulose finishing varnish instead. | 7th Oct 1930 | Box 59 \ 1 Scan010 | |
| Copy of a letter from a supplier in Manchester quoting prices for various specifications of standard cables. | 4th Dec 1931 | Box 59 \ 1 Scan011 | |
| From W.T. Glover & Co. Limited detailing payment and delivery terms. | 17th Feb 1932 | Box 59 \ 1 Scan012 | |
| Chassis wiring and cable samples received from the supplier Ripaults Ltd. | 17th Feb 1932 | Box 59 \ 1 Scan013 | |
| Samples of cable for chassis wiring received from British Insulated Cables Ltd. | 18th Feb 1932 | Box 59 \ 1 Scan014 | |
| Letter to Ripaults Ltd. regarding samples of Ripogloss Cables for L.T. automobile wiring. | 25th Feb 1932 | Box 59 \ 1 Scan015 | |
| Letter from Ripaults Ltd. discussing the supply and pricing of their RIPOGLOSS electric cables. | 26th Feb 1932 | Box 59 \ 1 Scan016 | |
| Request to obtain various lengths and types of varnished fabric covered chassis cable from Ripaults Ltd. | 9th Mar 1932 | Box 59 \ 1 Scan017 | |
| Cable standards and requesting a price comparison between Glover L.T. and Ripault cables. | 9th Mar 1932 | Box 59 \ 1 Scan018 | |
| Quotation letter for different types of low tension chassis wiring flexibles. | 17th Mar 1932 | Box 59 \ 1 Scan019 | |
| Letter from a supplier detailing prices, payment terms, and specifications for flexible coloured cables. | 17th Mar 1932 | Box 59 \ 1 Scan020 | |
| Concerns over volt drop from a proposed wiring method for the 'Japan 3' and comparing it to the 20/25 HP scheme. | 8th Mar 1932 | Box 59 \ 1 Scan021 | |
| Current electrical wiring system and considering an alternative seen on an Alfa Romeo. | 5th Apr 1932 | Box 59 \ 1 Scan022 | |
| Condition of standard chassis wiring and considering the use of alternative Sistoflex cables. | 1st Apr 1932 | Box 59 \ 1 Scan023 | |
| Order for various lengths and colours of varnished fabric covered chassis cable. | 9th May 1932 | Box 59 \ 1 Scan024 | |
| Fitting and comparing Ripogloss and Glover's cables on experimental chassis. | 15th Sep 1932 | Box 59 \ 1 Scan025 | |
| Reference note pointing to previous correspondence files. | 18th Jan 1932 | Box 59 \ 1 Scan026 | |
| Defective Dynamo, No. JB.45, from chassis 11-JS, sent for examination and report. | 18th Jan 1932 | Box 59 \ 1 Scan027 | |
| Complaint about a defective coil causing misfires on chassis GBM-64. | 22th Jan 1932 | Box 59 \ 1 Scan028 | |
| Total battery discharge for chassis GPS-1 belonging to Mrs. Cadbury. | 22th Feb 1932 | Box 59 \ 1 Scan029 | |
| Letter to Bosch Ltd. regarding a battery fault on a customer's chassis. | 2nd Mar 1932 | Box 59 \ 1 Scan030 | |
| Rumoured breakdown of a Bosch dynamo on Mr. Walter Iden's Phantom chassis. | 3rd Mar 1932 | Box 59 \ 1 Scan031 | |
| Follow-up memo confirming customer satisfaction with a rectified battery issue on chassis 119-GN. | 10th Mar 1932 | Box 59 \ 1 Scan032 | |
| Letter from Bosch Limited responding to an enquiry about battery trouble on a Mr. Walter Idens' chassis. | 31th Mar 1932 | Box 59 \ 1 Scan033 | |
| Request to examine a failed starter motor from chassis 189-GY, report on the cause of failure, and advise on cost allocation. | 9th Apr 1932 | Box 59 \ 1 Scan034 | |
| The return of a faulty starter motor from chassis No.189-GY and requesting an urgent report on the recurring issue. | 6th Apr 1932 | Box 59 \ 1 Scan035 | |
| Investigating a complaint about a starter motor on chassis 189.GY. | 11th Apr 1932 | Box 59 \ 1 Scan036 | |
| The handling of a request for information on Chassis No. 189-GY. | 12th Apr 1932 | Box 59 \ 1 Scan037 | |
| Starter motor fault on Chassis 189 GY with reference to Derby's report. | 12th Apr 1932 | Box 59 \ 1 Scan038 | |
| Motor complaint on chassis 189-GY, diagnosing a voltage loss on the system as the likely cause. | 4th Apr 1932 | Box 59 \ 1 Scan039 | |
| Internal memorandum regarding a customer's persistent starter motor issues and proposed further investigation. | 15th Apr 1932 | Box 59 \ 1 Scan040 | |
| Recurring dynamo failure on chassis GUK.60, suggesting an installation issue. | 29th Apr 1932 | Box 59 \ 1 Scan041 | |
| Recurring faulty dynamos on a 20/25 chassis GUK.60 due to a defective dynamo-battery circuit connection. | 3rd May 1932 | Box 59 \ 1 Scan042 | |
| Service sheet detailing the cause and remedy for dynamo overheating on 40/50 and 20/25 chassis. | 4th May 1932 | Box 59 \ 1 Scan043 | |
| Recurring issues with faulty dynamos, attributing the cause to system faults rather than the dynamos themselves. | 4th May 1932 | Box 59 \ 1 Scan044 | |
| Wording of a Depot Sheet regarding dynamo trouble, comparing it to an Instruction Book. | 10th May 1932 | Box 59 \ 1 Scan045 | |
| Suggesting revised wording for a depot sheet regarding dynamo operation and battery circuit integrity. | 9th May 1932 | Box 59 \ 1 Scan046 | |
| Returned flywheel and starter motor from chassis GMU-30 due to a complaint of jamming and knocking. | 12th Oct 1932 | Box 59 \ 1 Scan047 | |
| Customer complaint regarding a failed dynamo on Chassis GZU-11 and its return for examination. | 16th Nov 1932 | Box 59 \ 1 Scan048 | |
| Report regarding a returned Dynamo (D.52450) that only required cleaning of grease from the commutator. | 18th Nov 1932 | Box 59 \ 1 Scan049 | |
| Battery charging issues and potential solutions for a customer's car used in strenuous mountain conditions. | 29th Nov 1932 | Box 59 \ 1 Scan050 | |
| Customer's vehicle issues, specifically concerning cold starts, dynamo charge rates, and vibrator control. | 20th Nov 1932 | Box 59 \ 1 Scan051 | |
| Dynamo performance and potential modifications for a customer's car. | 20th Nov 1932 | Box 59 \ 1 Scan052 | |
| Typed memo discussing customer service issues regarding battery problems, vibrator-control, and fitting a special output switch to a car. | 1st Dec 1932 | Box 59 \ 1 Scan053 | |
| Letter providing advice on protecting a car from very cold weather conditions. | 1st Dec 1938 | Box 59 \ 1 Scan054 | |
| Typed letter discussing cold weather vehicle operation, including anti-freeze and battery charging. | 21th Dec 1938 | Box 59 \ 1 Scan055 | |
| Letter concluding a discussion on potential damage to an armature from battery conditions. | 21th Dec 1938 | Box 59 \ 1 Scan056 | |
| Production of another set of Three-charge scheme units for Chassis GEX.29 for Doctor Vernon. | 22th Dec 1932 | Box 59 \ 1 Scan057 | |
| Customer's battery, recommending an upgrade to a larger capacity battery and a constant voltage dynamo system for chassis 38-MY. | 16th Sep 1933 | Box 59 \ 1 Scan058 | |
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