Determining Decibels
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DV using transistors Dawe Instruments, LP Ltd., 99 Uxbridge Road, London, W.), have produced a self-contained sound level meter with overall dimensions of 81 in. by 5+ in. by 3i in. which weighs only 4 lb. The type 1400 E meter, as it is designated, could be used to measure the noise produced by a vehicle or the sound level in passenger compartments. It could also be employed to check the quiet running of transmission components, and similar items. The unit • incorporates a microphone and the reading is indicated on a semi-circular scale. It is powered by a dry battery.
Theft Prevention A COMBINATION lock which I—I replaces the normal ignition switch is the basis of an anti-theft device for vehicles developed by Mr. A. T. V. Johnson of the Melton Garage and Engineering Co., Ltd., Melton Mowbray, Leics. The lock breaks the electrical circuit until the correct combination has been applied to its dial. When the vehicle is left unattended an additional switch is put in the " on " position to guard the main lock, with the effect that, if the lock is tampered with,. the vehicle's horn or an additional warning device is brought into action. The doors of the vehicle can be protected by a second combination switch.
Hydraulic Hose A BRITISH-MADE hydraulic brake tAhose reinforced with high-tenacity synthetic fibre has received the approval of the American Society of Automotive Engineers. Prior to this, only hose incorporating rubber had met their stringent specification. The hose and its metal end fittings are manufactured by Tecalernit, Ltd.,Plymouth, Devon, who state that the complete assembly greatly exceeded the A.S.A.E. safety and performance requirements. A number of American vehicle manufacturers arc already testing the Tecalemit hoses.
Rope Marketing TOW ropes produced by R. Perry .and Co., Ltd., 90 Church Street, Birkenhead, have been marketed for many years by Holt Products, Ltd. This arrangement has been discontinued and the ropes are now available direct from the manufacturers. Two types are offered. The KKL toggle rope requires no special fittings. a
Each end carries cross-piece which is
passed around the axle or other towing member and then pushed through a double section of the rope to form a c22 loop. The sizes available are suitable for towing 14, 3 and 5 tons. The KKL nylon rope is 1 in. in circumference and 12 ft. long. Conventional shackles are fitted at its ends and it has a breaking strain of 2,000 lb.
ljt ATTERY-POWERED telenhones are Telephone Hire ljt ATTERY-POWERED telenhones are
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1-; offered for hire by Harvid Co-modifies, Ltd., 84 Baker Street, London, W.I. The handset units are. self-contained and can be connected up by the hirer using ordinary bell wire. They are . powered by dry batteries.
The units can be rented for as short a
period as three months and cost 4s. a week for two instruments or 3s. a week or hire of two years or over. This charge includes replacement of batteries.
First Aid ADHESIVE plaster in a novel pack 1-1. which makes it particularly suitable for carrying in the document pocket or dashboard compartment of a vehicle is offered by Trico-Folberth. Ltd., Great West Road, Bientford, Middlesex. The plasters are wrapped in transparent plastics sheet and contained in a coloured plastics cover to make up a booklet,
hence the name, Plastabook. It costs 3s. 6d.
Clean Cutting THE tungsten arc process originally developed by the Linde C ny ompa of the Union Carbide Corporation for cutting metals such readily oxidized h as aluminium, stainless steel, titanium and copper, is now marketed in this country by British Oxygen Gases, .Ltd., am water House. Cleveland Row, St. Jes's, London, S.W.I. in arrangement with Union Carbide, Ltd., 103 Mount Street, London, W.I. A non-consumable electrode working in a stream of gas is the basis of the process provides a high cutting rate
which p and metallurgically clean cut edge leaves a free from contamination.
Concrete Dumper A' improved concrete-carrying body is offered by E. Boyden and Co., Ltd., Old Trafford, Manchester, for use with the standard Muir-Hill 10B hydraulic dumper. The body has a liquid capacity of 2 cu. yd. on a 1 in 10 gradient. The unit is primarily designed for carrying concrete from batching plants to sites in cases where the distance is too short to merit agitators or vehiclemounted mixers. It provides a tipping height of 4 ft. 6 in. For slow discharge when partially tipped a vibrator unit can be fitted below the body mouth, whilst a chute can be supplied for ground level delivery.
Six-wheeler Braking A RECOMMENDATION MENDATION for the rx layout of braking systems on fourwheeled vehicles converted to six-wheelers by the addition of a trailing axle has been put forward by the Clayton Dcwandre Co., Ltd., Titanic Works, Lincoln. On some conversions the hydraulic brakes on the third axle have been connected direct to the existing Hydrovac on the original vehicle. However, this unit is not of sufficient capacity to operate brakes on three axles. The correct practice is to introduce an additional slave vacuum-hydraulic servo, with its own reservoir, into the system to provide third axle braking.