Alexandra Palace Research Articles

The Literature of English Post-Medieval Pottery

AT THE Spring Conference in 1965, one of the writers of the present article put in a mild plea for justice to be',done to the older writers on English ceramics, and this address was reproduced in Broadsheet NO.3 of the Post-Medieval Ceramic Research Group, as the Society then was. When the question of reprinting some of the old Broadsheets came up, it was suggested that this somewhat discursive foray into the realm of bibliography might be worked into something of more general usefulness to those not already familiar with the thickets of English ceramic bibliography. I 'Old books are best', and it is often surprising when trying to find one's way back to the sources of ceramic information how fresh and modern some of the older books strike, and how much fundamental spade-work was accomplished at the earliest stage of the growth of this literature-work consciously or unconsciously plagiarized by all writers on the subject since. One of the earliest was J. Marryat's Collections towards a history of Pottery and Porcelain, the first edition of which came out in 1850, and which contains much material on English wares. Not long after came the first edition of Chaffers's Marks and Monograms on Pottery and Porcelain (London, 1863), much of which also was devoted to English Ceramics. The latter work has come out in innumerable editions since, and it is now impossible, without going methodically back through successive revisions, to be sure what is the original Chaffers and what the work of subsequent editors. The book is unreliable, but often contains information which is not found in other sources but which it is well worth following up, provided that it is cross-checked by every means available. The earliest extensive work devoted exclusively to the pottery and porcelain of the British Isles is LlewellynnJewitt's The Ceramic Art of Great Britain (London, 1878), although R. H. Soden-Smith had already in 1873 brought out a Catalogue of the English Pottery and Porcelain at Alexandra Palace: Jewitt remains a fundamental work in ceramic research. Although much of it has been rendered obsolete by subsequent investigations, and some of it has been shown to be ,vrong, it is invaluable for its documentary basis. Much of the archival material was in Jewitt's own possession, and much of it has since been lost. For the basic history of the pottery industry in the 19th century it is indispensable. As 'with Chaffers, the cautious reader will take care to cross-check his facts in every way possible; but Jewitt is far the more reliable authority. In the field of English pottery alone, L. M. Solon's The Art of the Old English Potter (London, 1883), is probably to be regarded as the pioneer work. Solon was

Forthcoming events and other notices

Forthcoming events and other noticesPublished Online:28 Jan 2014https://doi.org/10.1259/0007-1285-42-493-76SectionsPDF/EPUB ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InEmail AboutAbstractThe Annual Physics Exhibition for 1969 will be held in Alexandra Palace, Wood Green, London, N.22, from March 10–13, 1969. There will be a large distribution of complimentary tickets by the exhibitors and to members of The Institute of Physics and The Physical Society and the Press; the price of admission otherwise will be 2/6d. Previous article Next article FiguresReferencesRelatedDetails Volume 42, Issue 493January 1969Pages: 1-80 © The British Institute of Radiology History Published onlineJanuary 28,2014 Metrics Download PDF

1968 Physics Exhibition

It is generally agreed that the 1968 Physics Exhibition was a marked success particularly in comparison with the 1967 exhibition. The number of exhibitors in all classes showed an increase, although not yet to the level of 1964, and the number of visitors was the greatest yet recorded at Alexandra Palace (18 000), surpassing by almost 50% the figure for 1967 (12 600).

Exhibitions: Seen at the Physics Exhibition, Alexandra Palace, March 11th – 14th, 1968

exhibitions: Seen at the Physics Exhibition, Alexandra Palace, March 11th – 14th, 1968

Vacuum equipment at the physics exhibition 1967

As in previous years, vacuum equipment developed in the previous twelve months was shown on several stands at the 51st Exhibition of Scientific Instruments and Apparatus organised by the Institute of Physics and The Physical Society and held at Alexandra Palace, London, from 17th to 20th April, 1967. The main interest was in the displays of the number of vacuum equipment manufacturers now marketing plant and accessories in Britain. Here the novelty of apparatus shown varied considerably from one manufacturer to another, chiefly because the old established firms had to show gear of more genuine originality than the younger firms who were able to exhibit products new to their programme but not really new in the development of vacuum technology. A survey of the vacuum equipment on show can be divided into three sections: (a) accessories developed by firms and research organisations not primarily interested in vacuum plant and components; (b) vacuum apparatus by Mullard Ltd and Associated Electrical Industries Ltd (Scientific Apparatus Department) to whom the marketing of such plant is an important but comparatively small part of their wide-scale activities in science and technology; and finally, (c) the UK firms of Edwards High Vacuum International Ltd, Vacuum Generators Ltd, Bir-Vat Ltd, NGN Ltd and Genevac Ltd to whom “vacuum” is basic “bread and butter” sales. In addition, exhibits were organised by Veeco Instruments who are a subsidiary of the American parent firm and E Leybold’s Nachfolger, the German firm, as part of the display by the Ministry of Scientific Research of the Federal Republic of Germany. Users of vacuum equipment have such a wide variety of interests that it is difficult during a visit to select all those items shown by organisations within category (a). The following list cannot therefore be claimed to be exhaustive. The Plessey Co Ltd apparatus for obtaining the velocity distribution amongst atoms evaporated in V(ICUO from “flash” and “oven” sources. The interest to cryogenic and cryopumping devotees of the range of liquid helium cryostats, the self-contained helium refrigerator and the mobile dispenser for liquid nitrogen of the British Oxygen Co Ltd and the first production model of the Mark III “Harwell” refrigerator capable of O.OS”K and a liquid nitrogen pump able to control delivery rate from 0 to 4 litre per min of the Oxford Instrument Co Ltd. The 10 kVA high temperature vacuum furnace in which a maximum temperature of 2400°C can be maintained at a pressure of 1O-5 torr of Spembly Technical Products Ltd. Montford Instruments Ltd space simulator. The air-lock chamber for an electron microscope developed by the University of Cambridge. The equipment for the production of single crystal layers of silicon of very high purity by evaporation in ultrahigh vacuum, a vacuum cleaving and surface decorating apparatus and an ion beam source for producing layers of silicon and of gallium Edwards’ new vacuum coater

B.R. Research Laboratories in London

New laboratories, built on the site of the former Alexandra Palace railway station at Muswell Hill, London, were formally opened last March by Sir Brian Robertson, chairman of the British Transport Commission. The new building contains laboratories and offices for the chemical services and completes the first stage in the reorganisation and expansion of the B.R. research department.

The London-Birmingham television-cable system

The London-Birmingham television-cable system provides channels for relaying television signals between central points in the two cities, in both directions simultaneously, with extensions to the television transmitters at Alexandra Palace and Sutton Coldfield, a total of five links being involved.The vision-frequency signals modulate a carrier of 6.12 Mc/s at the sending-end, the lower-sideband, the carrier and part of the upper-sideband being transmitted over the cable. The transmission paths are provided by coaxial pairs approximately one inch in diameter, equipped with repeaters nominally at 12-mile intervals, the gain and delay being substantially constant from 3 to 7 Mc/s. In the event of repeater failure, change-over from working to standby repeaters is automatic, and power for some of the intermediate repeater stations is supplied over the coaxial pairs themselves. At the receiving end the signals are passed through an asymmetric-sideband-shaping filter before the vision-frequency signal is recovered by envelope detection.The overall vision-frequency characteristics of the London-to-Birmingham channel, in tandem with the Alexandra Palace and Sutton Coldfield extensions, show a total variation in gain of 0.8 db, and in phase delay of 0.04 microsec for frequencies up to 3 Mc/s. Above this frequency the cut-off is rapid. The performance in respect of linearity, signal/noise ratio and time response is adequate, and photographs are reproduced showing the effect on a television test-pattern of sending signals from London to Birmingham and back.

Television transmitting aerials

A reference to the Alexandra Palace television aerial and to the circumstances preceding the expansion of high-power television services in Great Britain serves as an introduction.The various mechanical and electrical considerations which affect the design of a transmitting aerial are then reviewed, particular attention being directed to common-aerial working for vision and sound. The properties of 2-phase aerial systems are discussed, and curves enabling the horizontal radiation patterns of such aerials to be interpreted in terms of impedance measurements on the distribution-feeder system are presented.The development of the Sutton Coldfield aerial is described, details being given of the scheme of admittance correction applied to the distribution feeder. The modifications to this basic design adopted for Holme Moss and the later high-power stations are explained.The paper concludes with speculations on the probable future trend of television transmitting-aerial design.

Television Development in Britain

AN important statement was issued on August 24 outlining the Government‘s policy on the development of television in Great Britain. It will be recalled that the Television Committee, under the chairmanship of Lord Hankey, issued its report early in 1945 with a number of specific recommendations on the manner in which, after the War, a public television service should be resumed and developed in Britain (see Nature, 155, 615 ; 1945). Acting with commendable speed and efficiency, the B.B.C. implemented the first of the recommendations by reopening the London Television Service from the Alexandra Palace Station in June 1946. Next, with the view of extending the existing service to other parts of the country, work was begun on a similar station near Birmingham.

The First Television Broadcast of “Wuthering Heights”

Abstract“Wuthering Heights” was given its first television broadcast on March 7th, 1948, and I was there, among the confusing contraptions of the studio in Alexandra Palace, with a watching brief for the Bronte Society.It seems a far cry from High Withens to the late Victorian splendours of Alexandra Palace, and a much further one from the private processes of Emily Bronte's mind to the cerebral artifice of television. Perhaps I prepared for it, as an imaginative leap, with forebodings more acute than any the Brontes would have known.

Television after the War

ONE of the most remarkable achievements in the application of science to the everyday life of the community was the development of television before the War. The first public service of high-definition television, in Great Britain or any other country, was inaugurated at the British Broadcasting Corporation's station at Alexandra Palace in November 1936. Prior to the closing down of the station for military reasons in September 1939, the television service had reached a high standard; the programme technique had made great progress, and the result was a service of considerable entertainment value. Some twenty thousand television receivers were in use by the general public, and although the service was confined to the London area, it is probable that several hundred thousand persons were more or less regular 'viewers' either in their own homes or elsewhere. These and many others have probably been wondering for some time past exactly what are the prospects of television after the War, and to what extent the lead which Britain established in this field nearly ten years ago will be maintained in the future. There has naturally been some cause for anxiety in this matter, since the United States had the advantage of more than two years of continued development on an almost peace-time basis after the outbreak of war in Europe; and even to-day there are in the United States a number of television transmitting stations in operation on an experimental or other basis.

Principles of Television Engineering

PRIOR to the War, Great Britain had established a very advanced position in the application of radio communication to television broadcasting. The inauguration by the British Broadcasting Corporation of the London television station at Alexandra Palace in August 1936 marked the beginning of the first public television service in the world. Much scientific research and technical development in this subject were being actively pursued in several other European countries, and more particularly by various commercial organizations in the United States of America. Since the outbreak of war, the public development and application of television to broadcasting has been brought to a standstill in Great Britain, whereas the technique of the subject has continued to be very actively pursued in America during the past eighteen months. There is good reason to believe, however, that when happier times return, Great Britain will be able to recover a place in the front line of television broadcasting. A good deal of the technical work now being carried out for war purposes by radio engineers and physicists will probably find ready application to television problems when peace comes; while the recent demonstration given by Mr. J. L. Baird of television in natural colours indicates that the small amount of experimental work still in progress is already producing fruitful results.

Significance of Television

AN instructive address on television given at Buenos Aires last year by Mr. W. E. Tremain, chairman of the Argentine Centre of the Institution of Electrical Engineers, is published in the May issue of the Journal of the Institution of Electrical Engineers. Mr. Tremain begins by saying that the more we study recent developments in television, the more we are forced to realize that high-definition television is one of the outstanding scientific and engineering achievements of our time. In August 1936, the Alexandra Palace transmitter in north London was in full operation, giving the first public television service in the world. On May 12, 1937, the Coronation procession was televized with much success. It was the first outside television exhibition of importance. In conclusion, Mr. Tremain points out that television is destined to play in the future a leading part both as a means of communication and as a means of instruction. When planning for the future, it is important to bear this in mind. In England, as a result of pressure both from the cinema and radio industries, the experimental work being conducted for the purpose of extending the television service in the provinces was expedited. If a definite decision be taken with this end in view, we can look forward hopefully to it giving much direct employment in happier times.

Television Broadcasting

SIR NOEL ASHBRIDGE gives a review of the progress being made in broadcasting and television in the Proceedings of the Wireless Section of the Institution of Electrical Engineers of June. The period under review extends from the end of 1934 until the end of 1938. During this period the number of licence-holders in European countries has increased by more than 60 per cent. The details of the Royal tour in America in increasing the popularity of sound broadcasting have not yet been published, but it is known that the excellent broadcasts of sound and television have greatly increased the popularity of the British Broadcasting Company. The second part of Sir Noel's report deals exclusively with television broadcasting. The great improvements made in the quality of the pictures shown, the great trouble taken by the Government Post Office to locate the position and find out the cause of the interference, when complaints are made, and the remedies they suggest, in many cases completely eliminating the trouble, have satisfied the users in nearly every district. The nominal hours of transmission are now from 3 to 4 p.m.; and from 9 to 10 p.m. The vision transmitter and the studio and control room equipment at the Alexandra Palace Station have been considerably improved; in particular, an improved type of ‘Emitron’ tube, known as the long-gun type, is now in use for studio work. It is now possible to obtain very satisfactory results with telephoto lenses. Satisfactory reception is possible up to a radius of about thirty miles from the Palace. In exceptional cases reception has been reported up to 200 miles. It is hoped that in the future international standardization with regard to definition and picture frequency may become available, as the absence of a common standard would be a most serious drawback.

Discussion on the papers “Long feeders for transmitting wide side-bands, with reference to the Alexandra Palace aerial-feeder system”, by Messrs. Cork and Pawsey, and “E.M.I. cathode-ray television transmission tubes”, by Messrs. McGee and Lubszynski, before the Wireless Section, 7th December, 1938

Discussion on the papers “Long feeders for transmitting wide side-bands, with reference to the Alexandra Palace aerial-feeder system”, by Messrs. Cork and Pawsey, and “E.M.I. cathode-ray television transmission tubes”, by Messrs. McGee and Lubszynski, before the Wireless Section, 7th December, 1938

Long feeders for transmitting wide side-bands, with reference to the Alexandra Palace aerial-feeder system

The paper is concerned with reflection phenomena in long feeders used to transmit modulated high-frequency carrier waves such as television signals, in which the time of transmission of a wave along the feeder is comparable with the time periods of the modulation frequencies.The nature of the various impedance irregularities giving rise to reflection is discussed, and their effect on a received television picture is indicated. Methods for reducing the effect of these irregularities are considered.These reflecting irregularities may be studied in terms of the variation with frequency of the input impedance of the terminated feeder, and examples are given of the magnitude of the effects for various feeders.The vision aerial feeder system of the London Television Station is described, including the aerial-to-feeder matching arrangements and a device for reducing the residual mismatch due to the variation of the aerial impedance over the frequency range of the carrier and side-bands.Apparatus for measuring the input impedance and the methods adopted for establishing a standard resistance for terminating the feeder are described.In the Appendix consideration is given to the permissible limits of eccentricity of an approximately terminated but irregularly eccentric feeder.

The authors' replies to the discussion on “Long feeders for transmitting wide side-bands, with reference to the Alexandra Palace aerial-feeder system” and “E.M.I. cathode-ray television transmission tubes”

The authors' replies to the discussion on “Long feeders for transmitting wide side-bands, with reference to the Alexandra Palace aerial-feeder system” and “E.M.I. cathode-ray television transmission tubes”

Sound Transmission from London Television Station

IT is well known that the use of ultra-short wavelengths for broadcasting purposes facilitates the attainment of a very high quality in the sound transmission on account of the extensive range of side-band frequencies which may be employed. At a meeting of the Wireless Section of the Institution of Electrical Engineers on May 3, Messrs. I. L. Turn-bull and H. A. M. Clark read a paper on “The Marconi-E.M.I. Audio-Frequency Equipment at the London Television Station”. This paper outlines the requirements of a high-quality sound equipment and describes the design and constructional features of the Alexandra Palace installation. The final section of the paper gives information on the overall performance of the apparatus and includes data on the frequency and harmonic distortion of the amplifier equipment. The overall frequency response from the microphone to the modulated radio frequency output to the transmitter is practically uniform from 40 cycles per second to more than 10,000 cycles per second; the second harmonic content varies up to a maximum of 0-5 per cent for full (that is, 100 per cent) modulation, while at the same modulation level the third harmonic content is about 0-1 per cent. The authors express the opinion that it is this low odd-harmonic distortion, quite as much as the extended frequency range, that is responsible for the satisfying and pleasing quality of the sound transmitted. The equipment has been in operation for a period of two years with complete satisfaction. It may be remarked in conclusion that, for some time past, it has been the practice of the British Broadcasting Corporation to transmit part of the ordinary National or Regional programme through the Alexandra Palace ‘sound’ transmitter, so that listeners having a television or other suitable ultra-short wave receiver may take advantage of this high-quality broadcasting station.

Long feeders for transmitting wide side-bands, with reference to the Alexandra Palace aerial-feeder system

The paper is concerned with reflection phenomena in long feeders used to transmit modulated high-frequency carrier waves such as television signals, in which the time of transmission of a wave along the feeder is comparable with the time periods of the modulation frequencies. The nature of the various impedance irregularities giving rise to reflection is discussed, and their effect on a received television picture is indicated. Methods forreducing the effect of these irregularities are considered. These reflecting irregularities may be studied in terms of the variation with frequency ofthe input impedance of the terminated feeder, and examples are given of themagnitude of the effects for various feeders. The vision aerial feeder system of the London Television Station is described, including the aerial-to-feeder matching arrangements and a device for reducing the residual mismatchdue to the variation of the aerial impedance over the frequency range of the carrier and side-bands. Apparatus for measuring the input impedance and the methods adopted for establishing a standard resistance for terminating the feeder are described. In the Appendix consideration is given to the permissible limits of eccentricity of an approximately terminated but irregularly eccentric feeder.

Discussion on the papers “Long feeders for transmitting wide side-bands, with reference to the Alexandra Palace aerial-feeder system”, by Messrs. Cork and Pawsey, and “E.M.I. cathode-ray television transmission tubes”, by Messrs. McGee and Lubszynski, before the Wireless Section, 7th December, 1938

Discussion on the papers “Long feeders for transmitting wide side-bands, with reference to the Alexandra Palace aerial-feeder system”, by Messrs. Cork and Pawsey, and “E.M.I. cathode-ray television transmission tubes”, by Messrs. McGee and Lubszynski, before the Wireless Section, 7th December, 1938