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Federal Communications Commission § 74.789
Federal Communications Commission § 74.789 In addition, any outstanding construc- (3) Applications for extension of time tion permit (analog or digital) for an shall be filed not later than May 1, channel above Channel 51 will be re- 2015, absent a showing of sufficient rea- scinded on December 31, 2011, and any sons for late filing. pending application (analog or digital) (d) For construction deadlines occur- for a channel above Channel 51 will be ring after September 1, 2015, the tolling dismissed on December 31, 2011, if the provisions of § 73.3598 of this chapter permittee has not submitted a digital shall apply. displacement application by 11:59 pm (e) A low power television, TV trans- local on September 1, 2011. lator or Class A television station that holds a construction permit for an un- [69 FR 69333, Nov. 29, 2004, as amended at 74 FR 23655, May 20, 2009; 76 FR 44828, July 27, built analog and corresponding unbuilt 2011] digital station and fails to complete construction of the analog station by § 74.788 Digital construction period. the expiration date on the analog con- struction permit shall forfeit both the (a) Each original construction permit analog and digital construction per- for the construction of a new digital mits notwithstanding a later expira- low power television or television tion date on the digital construction translator station shall specify a pe- permit. riod of three years from the date of (f) A low power television, TV trans- issuance of the original construction lator or Class A television station that permit within which construction shall holds a construction permit for an un- be completed and application for li- built analog and corresponding unbuilt cense filed. -
The Future of Human-Computer Interaction: Overview of Input Devices
The future of human-computer interaction: overview of input devices Fabrizio Fornari School of Computer Science H´ask´olinn´ıReykjav´ık- Reykjav´ıkUniversity Reykjav´ık,Iceland November, 2012 Abstract We are in 2012 and we are still using the mouse and the keyboard to interact with a computer. We have seen a lot of changes in the world of Computer Science, relating to: performance, design and the way we interact with the computer. Differ- ent input devices have been developed around the computer, starting from the most recent touchscreens, continuing with webcams, microphones, and arriving to the oldest mice and keyboards. The aim of this research is to let the reader imagine a new way to interact with the computer. To reach our purpose, we introduce advanced technologies such as: Speech and Voice Recognition, Electronic Perception, Eye Tracking and Brain Computer In- terfaces. We propose examples of the cited technologies that may change the paradigm that saw, until now, keyboard and mouse as leaders of the input devices. 1 1 Introduction From the computer's birth1, we saw a lot of changes in the world of Com- puter Science. Changes relating to: performance, design and human-computer interaction [49]. A few years ago, the words \input device" evoked in our mind only two specific objects: the keyboard and the mouse - the main instruments used to provide data to a personal computer. Keyboard and mouse are, in fact, two of the first input devices in the history of computer. Nowadays, with the evolution of computers, we have a large set of input de- vices that changed the way we interact with the computer. -
Radio Wave Spectrum Allocations and Dial Markings on Old Radios – Page 1
Radio Wave Spectrum Allocations and Dial Markings on Old Radios – page 1 When you look at the dial of an old radio you may be confused by the numbers and letters written on the dial. In Australia and New Zealand the dials of Medium Wave radios (often called the Broadcast Band) were usually marked with the station call signs. In Australia, if the dial scale was quite small, a radio would only have the stations in that state marked on the dial. Some radios also had the Frequency and/or the Wave Length marked but this was not common throught period from 1936 to the end of the Australian made radios. Medium Wave Broadcast Band This is the band we tune to when we listen to an AM radio and most countries use frequency allocations between 526.5KHz and 1705KHz. Not all countries use all this allocation. Stereo transmission is possible and has been offered by some stations in the U.S., Canada, Mexico, the Dominican Republic, Paraguay, Australia, The Philippines, Japan, South Korea, South Africa, and France. However, there are multiple standards for AM stereo with C-QUAM being the most common in the United States as well as other countries, and receivers that implement the technologies are relatively rare. The FM Broadcast Band This is the range of frequencies we tune to when we tune a modern FM radio receiver. The international frequency allocation for this band is now 87.5MHz to 108MHz. This is often referred to as the CCIR Band. Over the years some countries have used other frequencies for this band and you will see these on the dials of some old FM radios you may find from time to time. -
Radio Communications in the Digital Age
Radio Communications In the Digital Age Volume 1 HF TECHNOLOGY Edition 2 First Edition: September 1996 Second Edition: October 2005 © Harris Corporation 2005 All rights reserved Library of Congress Catalog Card Number: 96-94476 Harris Corporation, RF Communications Division Radio Communications in the Digital Age Volume One: HF Technology, Edition 2 Printed in USA © 10/05 R.O. 10K B1006A All Harris RF Communications products and systems included herein are registered trademarks of the Harris Corporation. TABLE OF CONTENTS INTRODUCTION...............................................................................1 CHAPTER 1 PRINCIPLES OF RADIO COMMUNICATIONS .....................................6 CHAPTER 2 THE IONOSPHERE AND HF RADIO PROPAGATION..........................16 CHAPTER 3 ELEMENTS IN AN HF RADIO ..........................................................24 CHAPTER 4 NOISE AND INTERFERENCE............................................................36 CHAPTER 5 HF MODEMS .................................................................................40 CHAPTER 6 AUTOMATIC LINK ESTABLISHMENT (ALE) TECHNOLOGY...............48 CHAPTER 7 DIGITAL VOICE ..............................................................................55 CHAPTER 8 DATA SYSTEMS .............................................................................59 CHAPTER 9 SECURING COMMUNICATIONS.....................................................71 CHAPTER 10 FUTURE DIRECTIONS .....................................................................77 APPENDIX A STANDARDS -
History of Radio Broadcasting in Montana
University of Montana ScholarWorks at University of Montana Graduate Student Theses, Dissertations, & Professional Papers Graduate School 1963 History of radio broadcasting in Montana Ron P. Richards The University of Montana Follow this and additional works at: https://scholarworks.umt.edu/etd Let us know how access to this document benefits ou.y Recommended Citation Richards, Ron P., "History of radio broadcasting in Montana" (1963). Graduate Student Theses, Dissertations, & Professional Papers. 5869. https://scholarworks.umt.edu/etd/5869 This Thesis is brought to you for free and open access by the Graduate School at ScholarWorks at University of Montana. It has been accepted for inclusion in Graduate Student Theses, Dissertations, & Professional Papers by an authorized administrator of ScholarWorks at University of Montana. For more information, please contact [email protected]. THE HISTORY OF RADIO BROADCASTING IN MONTANA ty RON P. RICHARDS B. A. in Journalism Montana State University, 1959 Presented in partial fulfillment of the requirements for the degree of Master of Arts in Journalism MONTANA STATE UNIVERSITY 1963 Approved by: Chairman, Board of Examiners Dean, Graduate School Date Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. UMI Number; EP36670 All rights reserved INFORMATION TO ALL USERS The quality of this reproduction is dependent upon the quality of the copy submitted. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if material had to be removed, a note will indicate the deletion. UMT Oiuartation PVUithing UMI EP36670 Published by ProQuest LLC (2013). -
Comparison of Available Methods for Predicting Medium Frequency Sky-Wave Field Strengths
NTIA-Report-80-42 Comparison of Available Methods for Predicting Medium Frequency Sky-Wave Field Strengths Margo PoKempner us, DEPARTMENT OF COMMERCE Philip M. Klutznick, Secretary Henry Geller, Assistant Secretary for Communications and Information June 1980 I j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j TABLE OF CONTENTS Page LIST OF FIGURES iv LIST OF TABLES iv ABSTRACT 1 1. INTRODUCTION 1 2. CHRONOLOGICAL DEVELOPMENT OF MF FIELD-STRENGTH PREDICTION METHODS 2 3. DISCUSSION OF THE METHODS 4 3.1 Cairo Curves 4 3.2 The FCC Curves 7 3.3 Norton Method 10 3.4 EBU Method 11 3.5 Barghausen Method 12 3.6 Revision of EBU Method for the African LF/MF Broadcasting Conference 12 3.7 Olver Method 12 3.8 Knight Method 13 3.9 The CCIR Geneva 1974 Methods 13 3.10 Wang 1977 Method 15 3.11 The CCIR Kyoto 1978 Method 15 3.12 The Wang 1979 Method 16 4. -
The Beginner's Handbook of Amateur Radio
FM_Laster 9/25/01 12:46 PM Page i THE BEGINNER’S HANDBOOK OF AMATEUR RADIO This page intentionally left blank. FM_Laster 9/25/01 12:46 PM Page iii THE BEGINNER’S HANDBOOK OF AMATEUR RADIO Clay Laster, W5ZPV FOURTH EDITION McGraw-Hill New York San Francisco Washington, D.C. Auckland Bogotá Caracas Lisbon London Madrid Mexico City Milan Montreal New Delhi San Juan Singapore Sydney Tokyo Toronto McGraw-Hill abc Copyright © 2001 by The McGraw-Hill Companies. All rights reserved. Manufactured in the United States of America. Except as per- mitted under the United States Copyright Act of 1976, no part of this publication may be reproduced or distributed in any form or by any means, or stored in a database or retrieval system, without the prior written permission of the publisher. 0-07-139550-4 The material in this eBook also appears in the print version of this title: 0-07-136187-1. All trademarks are trademarks of their respective owners. Rather than put a trademark symbol after every occurrence of a trade- marked name, we use names in an editorial fashion only, and to the benefit of the trademark owner, with no intention of infringe- ment of the trademark. Where such designations appear in this book, they have been printed with initial caps. McGraw-Hill eBooks are available at special quantity discounts to use as premiums and sales promotions, or for use in corporate training programs. For more information, please contact George Hoare, Special Sales, at [email protected] or (212) 904-4069. TERMS OF USE This is a copyrighted work and The McGraw-Hill Companies, Inc. -
Guidelines for FM Broadcast Standards
TECHNICAL GUIDELINES FOR FM BROADCAST STANDARDS Directorate of Technical Regulations February 2014 94, Kairaba Avenue, P. O. Box 4230 Bakau, The Gambia Tel. (220) 4399601 / 4399606 Fax: (220) 4399905 EMail: [email protected] Website: www.pura.gm Contents 1. DEFINITIONS ........................................................................................................................... 2 2. INTRODUCTION ...................................................................................................................... 3 3. CLASSES OF FM BROADCAST STATIONS ........................................................................ 3 3.1 Public/Commercial FM station .................................................................................................. 3 3.2 Community Fm Stations ............................................................................................................. 3 3.3 Educational/Scientific FM station [Non Commercial] ............................................................... 3 4. FREQUENCY SPACING .......................................................................................................... 3 5. TECHNICAL REQUIREMENTS ............................................................................................. 4 5.1 Safety Requirements ................................................................................................................... 4 5.2 Transmitting Facilities ............................................................................................................... -
Federal Communications Commission § 80.110
SUBCHAPTER D—SAFETY AND SPECIAL RADIO SERVICES PART 80—STATIONS IN THE 80.71 Operating controls for stations on land. MARITIME SERVICES 80.72 Antenna requirements for coast sta- tions. Subpart A—General Information 80.74 Public coast station facilities for a te- lephony busy signal. GENERAL 80.76 Requirements for land station control Sec. points. 80.1 Basis and purpose. 80.2 Other regulations that apply. STATION REQUIREMENTS—SHIP STATIONS 80.3 Other applicable rule parts of this chap- 80.79 Inspection of ship station by a foreign ter. Government. 80.5 Definitions. 80.80 Operating controls for ship stations. 80.7 Incorporation by reference. 80.81 Antenna requirements for ship sta- tions. Subpart B—Applications and Licenses 80.83 Protection from potentially hazardous RF radiation. 80.11 Scope. 80.13 Station license required. OPERATING PROCEDURES—GENERAL 80.15 Eligibility for station license. 80.17 Administrative classes of stations. 80.86 International regulations applicable. 80.21 Supplemental information required. 80.87 Cooperative use of frequency assign- 80.25 License term. ments. 80.31 Cancellation of license. 80.88 Secrecy of communication. 80.37 One authorization for a plurality of 80.89 Unauthorized transmissions. stations. 80.90 Suspension of transmission. 80.39 Authorized station location. 80.91 Order of priority of communications. 80.41 Control points and dispatch points. 80.92 Prevention of interference. 80.43 Equipment acceptable for licensing. 80.93 Hours of service. 80.45 Frequencies. 80.94 Control by coast or Government sta- 80.47 Operation during emergency. tion. 80.49 Construction and regional service re- 80.95 Message charges. -
Reception of Skywave Signals Near a Coastline
JOURNAL OF RESEARCH of the National Bureau of Standards-D. Radio Propagation Vol. 67D, No.3, May- June 1963 Reception of Skywave Signals Near a Coastline J. Bach Andersen Contribution from Laboratory of Electromagnetic Theory, The Technical University of Denmark, Copenhagen, Denmark (Recei\'ed November 5, 1962) An experimental investigation has been made on t he influence of gt'ou nd inhomoge neities on the reception of skywave sig nals, especiall y t he in fluence of the conductivity contrast ncar a coastline. This gives rise to a r apid decrease in fi eld strength ncar til(' coastline as is "'ell known from g roundwave mixed path theory. Comparison with Lheory is given. Infl uC'llce of dilhts(' reflection from t he ionosplwre is also cOIl :; idereri . 1. Introduction conditions, i. e., a s Lraight boundary lin e, n,lt <l IH1 homogeneo us sectiollS , it was co nsidered worthwhile ;,lany factors influence the radiation 01' reception to measure tbe field in tensity at a n actual reception of skywave signals in the shortw,we ra nge, a nd in site in order to find Lhe deviation s from the simple choosing a proper site for a HF-a ntenna it is impor theory. tant to evaluate the influence of the various factors. lnstead of m eftsuring t he verticlll radiation pat They include th e electrical parameters (the conduc tern aL d iIrerent distances from Lhe coastlin e, the tivity and the p ermi ttiv ity) of the groulld, hills, or fi eld intensity from a distf\nL Lran smitter was m eas clift's a nd other irregularities of the sbape of the ured simultaneo usly at two d ifr erent places. -
Article a Look at S&T Awareness
SISSA – International School for Advanced Studies Journal of Science Communication ISSN 1824 – 2049 http://jcom.sissa.it/ Article A look at S&T Awareness - Enhancements in India Chandra Mohan Nautiyal Basing mainly on author's direct involvement in some science communication efforts in India, and other reports, this contribution depicts and analyses the present science communication/ popularization scenario in India. It tries to dispel a myth that rural people don't require or don’t crave for S&T information. It discusses need for science and technology communication, sustaining curiosity and creating role models. Citing cases of some natural, 'unnatural' and organized events, it recounts how S&T popularization efforts have fared during the past decade and a half. It's made possible using print, AV and interactive media which, at times, require lot of financial inputs. However, this contribution shows that a number of natural and other phenomena can be used to convince people about power of S&T and in molding their attitude. The cases cited may be from India, but, with a little variation, are true for most of the developing and under- developed societies. 1. Introduction Considering that nearly half of the Indian population is engaged in agriculture but contributes only about one fifth to the GDP, indicates a malaise and calls for more scientific and methodical approach in the farming sector. A change is needed not only in the information base but also the attitude. Therefore, there is a need to examine the role of Science and Technology (S&T) in their lives and ways to improve the level. -
Interpretation and Utilization of the Echo
PROCEEDINGS OF THE IEEE, VOL. 62, NO. 6, JUNE 1974 673 Sea Backscatter at HF: Interpretation and Utilization of the Echo DONALD E. BARRICK, MEMBER, IEEE, JAMES M. HEADRICK, SENIOR MEMBER, IEEE, ROBERT W. BOGLE, DOUGLASS D. CROMBIE AND Abstract-Theories and concepts for utilization of HF sea echo are compared and tested against surface-wave measurements made from San Clemente Island in the Pacific in a joint NRL/ITS/NOAA Although the heights of ocean waves are generally small experiment. The use of first-order sea echo as a reference target for in terms of these radar wavelengths, the scattered echo is calibration of HF over-the-horizon radars is established. Features of the higher order Doppler spectrum can be employed to deduce the nonetheless surprisingly large and readily interpretable in principal parameters of the wave-height directional. spectrum (i.e., terms of its Doppler features. The fact that these heights are sea state); and it is shown that significant wave height can be read small facilitates the analysis of scatter using the perturbation from the spectral records. Finally, it is shown that surface currents approximation. This theory [2] produces an equation which and current (depth) gradients can be inferred from the same Doppler 1) agrees with the scattering mechanism deduced by Crombie sea-echo records. from experimental data; 2) properly predicts the positions of I. INTRODUCTION the dominant Doppler peaks; 3) shows how the dominant echo magnitude is related to the sea wave height; and 4) per mits an explanation of some of the less dominant, more com T WENTY YEARS ago Crombie [1] observed sea echo plex features of the sea echo through retention and use of the with an HF radar, and he correctly deduced the scatter higher order terms in the perturbation analysis.