As explained in the last IEEE EMC Newsletter, there existed an informal Newsletter before the start of the Institute of Radio Engineers (IRE) Professional Group on Radio Frequency Interference (PGRFI) in 1957. The Newsletter was edited by Rexford Daniels and 18 editions were published between 1955 and 1958.
Again, for purposes of historical preservation and for the interesting articles, we will be reproducing these Quasies and Peaks Newsletters in the IEEE EMC Newsletter over the next 17 issues.
Quasies and Peaks – April 1955 – Interference
Testing and Research Laboratory, Inc.; 150
Causeway Street, Boston 14, Massachusetts
EDITORIAL
The Symposium on Spurious Radiation – at the IRE Convention – dealt mostly with broad governmental and industrial problems and responsibilities. It was pointed out by several speakers, that many of the problems involved were more of a managerial than engineering nature; hence, in the future, an increasing number of questions would have to be settled by ‘presidents’ of companies as well as by their Chief Engineers.
It was felt that, to reach the ultimate objectives which would be necessary for a practical program of interference reduction, there would have to be dual responsibilities between sources of interference – and equipment being interfered with; as well as new classes of controls. It was considered impractical to place the full responsibility on transmitters of spurious radiation when, in many instances, improved receivers might be a part of the solution. Also, some means of certification of apparatus, which could not be licensed, might have to be considered. These questions would require a close co-operation between the FCC and industry.
Possibly the most important statement, which was made engineering-wise, was made by Mr. G. C. W. Browne, Controller of Telecommunications, Department of Transportation, Canada, in his talk “Control of Radio Interference in Canada.” In discussing the problems of applying and administering the limits now in force in Canada, he said:
“As we all are aware, the practical application of such limits tends to be rather complex and we feel therefore that every effort must be made to simplify procedures as much as possible. Measurement of radiation at VHF frequencies tends to be affected by a number of variables which are difficult to control, and serious consideration is being given to relying, initially at least, on measurements of conducted noise only, which are much more manageable and easy to make. This, of course, would apply only to appliances and possibly to TV receiver interference. Such measurements of conducted noise from TV receivers would include measurements with the antenna terminals grounded.”
National Conference on Aeronautical
Electronics to hold Radio Interference Session,
Dayton, Ohio, May 10, 1955
The National Conference on Aeronautical Electronics; presented by the Dayton Section of the IRE and the Professional Group of Aeronautical and Navigational Electronics, and participated in by The Institute of Aeronautical Sciences; will hold a Radio Interference Session at the Engineers Club, Dayton, Ohio, on May 10, 1955.
Subjects and Speakers are as follows:
- Low-Impedance Gaskets for Radio-Frequency Applications; V. Pulsifer, A. J. Hoehn – Armour Foundation.
- Measurement of Interference Fields About Aircraft; J. R. Stahmann – Lightning and Transients Research Institute.
- Radio Interference Control in Aircraft; A. L. Albin, J. E. McManus – Armour Research Foundation.
- A Study of Interference Between Messages from Independent Multiple Sources on a Single Channel; Lt. B. Buchanan – Cambridge Research center, USAF.
- Study of Noise Reduction by Feedback in Ultra-High Frequency Amplifiers; A. B. Glenn – Radio Corporation of America.
Military Will Probe Spurious Radiations
from Electronics, April, 1955
On page 7 of Electronics, April 1955, is a discussion of the Armour Research Foundation’s recent Conference. Excerpts are as follows:
“Increasing use of the radio spectrum has aggravated the problem of interference. Both government and industry have stepped up progress to reduce spurious radiation….”
“Results of the study (Armour) will be used to provide recommendations for a long-range program of research and development and to furnish guidance on measures which can be affected immediately to improve field operation and maintenance.”
“Cost – Interference control has become a significant part of the defense program. John W. Klotz of the Department of Defense, in an address before the symposium on radio interference reduction at Illinois Institute of Technology, pointed out that every area of equipment development has become involved in some phase of the interference problem to insure that the equipment will operate effectively. He said that the Department of Defense estimates its annual support of the interference control program to be in excess of $200 million.”
“Last year one piece of radar equipment required a $2-million program of interference control to make it operate properly in its equipment environments. The control program extends to fields such as power generators, x-ray machines, lighting fixtures, office machines, etc.”
NEWS ITEM
From Danton Walker’s column, London, March 15, 1955:
“Parliament is studying a bill that would require anyone operating any machine (hair dryer, vacuum cleaner, etc.) that might interfere with television or radio reception to get a “suppressor” to eliminate any distortion of programs.”
NEW BOOK
NOISE, by Albert van der Ziol, Prentice Hall, Inc.; 1954, 450 pp., $10.35.
Some chapter headings: Noise Measurements, Tube Noise at Low Frequencies, Tube Noise at High Frequencies, Practical Low-Noise Circuits, Excess Noise in Semiconductors and Vacuum Tubes, Noise in Feedback Circuits.
New Theory for Formation
of Thunderstorm Electricity
Bernard Vonnegut, Arthur D. Little, Inc., Cambridge, Massachusetts has advanced a new theory for formation of thunderstorm electricity. A short write-up explaining the theory appears on page 184 of Electronics, April, 1955.
New ASEA List of Military
Specifications and Standards
The Armed Services Electro-Standards Agency, Fort Monmouth, NJ has brought out ASEA List No. 100, Issue No. 37, 1 March 1955. This list covers those specifications, standards, and other publications prepared by the Armed Services Electro-Standards Agency and pertaining to electro-standard parts, materials, and processes.
New Shielded Transformer
Electro-Search, 4337 N. 5th Street, Philadelphia 40, Pennsylvania has brought out a completely shielded transformer which performs any normal transformer function at power frequencies but rejects the higher audio and radio frequencies with an insertion loss of over 100 dB from 100 kc to 1800 mc when measured in a 50-ohm system.
Pertinent Notes Concerning Interference
We are pleased to include, with this issue, a copy of “Pertinent Notes Concerning Interference” prepared by Mr. C. R. Billheimer, of Code 837, BuShips, Navy Department.
What Interest is There in Forming
a Technical Group?
We have been asked by several readers to sound out those in this field as to their interest in forming some sort of technical group, or Society, which would act as a focal point for exchange of information and technical matters. Have you any suggestions?
Bibliography
Requests for copies of the following Circulars should be addressed to Controller of Telecommunications, Department of Transport, Ottawa, Canada, and are available free of charge. EMC
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