Crystal Radio Projects Listening to Longwave ARRL RFI Book
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
AM Loop Antennas AM LOOP ANTENNAS Introduction
AM Loop Antennas AM LOOP ANTENNAS Introduction An AM loop antenna is one of the true marvels of electronics. Requiring no power, it takes advantage of the resonant properties of an inductor and a capacitor connected in parallel to receive weak AM stations. The "loop" part of the antenna is the inductor, and the tuning capacitor makes it resonate at a desired frequency. As a boy in Abilene in 1967, I discovered the basic principle of the loop antenna. By removing a relatively small spiral loop in my five tube table radio, and substituting a much larger loop salvaged from an older radio, I could receive my favorite station - KLIF from Dallas better. I hid the loop in a cardboard holder featuring the logo of a favorite rock band, and enjoyed many hours of good listening. Lacking the mathematical background to understand antenna theory - I could not take the concept to the next phase: designing my own loop. Nevertheless, the spiral loop - combined with the antenna section of the radio's tuning capacitor - formed a very good loop antenna. I understood quite well that the bigger the loop, the more stations I could receive. The schematic diagram of an AM loop antenna is shown below. It consists of an inductive winding, which is supported on a frame, and a variable tuning capacitor that can be salvaged from a junk radio. The inductive winding consists of a primary, which forms a resonant network with the tuning capacitor, and a secondary "sense" winding that can be connected to a radio. In practice, however, the sense winding is not needed if the loop antenna can be placed near the radio - mutual coupling will take place with the antenna in the radio. -
Sue: Hear Hidden Satell Rals Litow Filters Im Pro Reception Shor Ave Listeni Ij)Ginia to Zambia World Band Cente °Fl1uo O Iü S
o t is-sue: Hear Hidden Satell Rals litow Filters Im pro Reception Shor ave Listeni ij)ginia to Zambia World Band Cente °fl1Uo O iü s Plus: CB, S. EJT Pg:DOUDC43'- Ham Radio; 0C2',.FC9g I . lit LAST WORD ERFORLNCE THE ICOM IC -781 HF TRANSCEIVER TRANSMIT 14.195.134 .. r.. = PHONES t; R IC -781 14.205.00 DELAY DRIVE NB LEVEL BIK.WIDiH GC .-_ A , : '.DMP .IB R, GAIN MCROPHONE- 1[01-O45 AMU St7h Sv( Nothing compares to the captivating Whether you aspire to DX, contest or experience of operating the finest transceiver enjoy legendary performance, the IC -781 on the market, the IC -781. The exhilaration inspires countless hours of devoted of operating the IC-781 is matched only by attention. Backed by a service commitment the luxury of its crystal clear communications. second to none, four factory service centers Designed for rigorous operation, the and a one-year factory warranty, the IC -781 IC-781 is the result of extreme dedication, characterizes Icom's dedication to excellence. exceptional craftmanship precision and V I, Miki L: m ui: lti: :iÌ- 1. till, .,,,!t 1li.,1+. engineering. The IC -781 fuses tre perfect Hotline at 1-800-999-9877. blend of features such as driving power, CORPORATE HEADQUARTERS: ICOM America, Inc.. 2380 -116th .Ave. N.E.. Bellevue, WA 98004 incredible clarity, a Multi -Function CRT CUSTOMER SERVICE HOTLINE (206) 454.7619 CUSTOMER SERVICE CENTERS: 3150 Premier Drive, Suite 126. Irving. TX 75063 Display, Spectrum Scope and Icclm's 1777 Phoenix Parkway. Suite 201. Atlanta. -
Tektronix: Glossary Video Terms and Acronyms
Glossaryvideo terms and acronyms This Glossary of Video Terms and Acronyms is a compilation of material gathered over time from numer- ous sources. It is provided "as-is" and in good faith, without any warranty as to the accuracy or currency of any definition or other information contained herein. Please contact Tektronix if you believe that any of the included material violates any proprietary rights of other parties. Video Terms and Acronyms Glossary 1-9 0H – The reference point of horizontal sync. Synchronization at a video 0.5 interface is achieved by associating a line sync datum, 0H, with every 1 scan line. In analog video, sync is conveyed by voltage levels “blacker- LUMINANCE D COMPONENT E A than-black”. 0H is defined by the 50% point of the leading (or falling) D HAD D A 1.56 µs edge of sync. In component digital video, sync is conveyed using digital 0 S codes 0 and 255 outside the range of the picture information. 0.5 T N E 0V – The reference point of vertical (field) sync. In both NTSC and PAL CHROMINANCE N COMPONENT O systems the normal sync pulse for a horizontal line is 4.7 µs. Vertical sync P M is identified by broad pulses, which are serrated in order for a receiver to O 0 0 C maintain horizontal sync even during the vertical sync interval. The start H T 3.12 µs of the first broad pulse identifies the field sync datum, 0 . O V B MOD 12.5T PULSE 1/4” Phone – A connector used in audio production that is characterized -0.5 by its single shaft with locking tip. -
Questions of the CCIR (Düsseldorf, 1990)
This electronic version (PDF) was scanned by the International Telecommunication Union (ITU) Library & Archives Service from an original paper document in the ITU Library & Archives collections. La présente version électronique (PDF) a été numérisée par le Service de la bibliothèque et des archives de l'Union internationale des télécommunications (UIT) à partir d'un document papier original des collections de ce service. Esta versión electrónica (PDF) ha sido escaneada por el Servicio de Biblioteca y Archivos de la Unión Internacional de Telecomunicaciones (UIT) a partir de un documento impreso original de las colecciones del Servicio de Biblioteca y Archivos de la UIT. (ITU) ﻟﻼﺗﺼﺎﻻﺕ ﺍﻟﺪﻭﻟﻲ ﺍﻻﺗﺤﺎﺩ ﻓﻲ ﻭﺍﻟﻤﺤﻔﻮﻇﺎﺕ ﺍﻟﻤﻜﺘﺒﺔ ﻗﺴﻢ ﺃﺟﺮﺍﻩ ﺍﻟﻀﻮﺋﻲ ﺑﺎﻟﻤﺴﺢ ﺗﺼﻮﻳﺮ ﻧﺘﺎﺝ (PDF) ﺍﻹﻟﻜﺘﺮﻭﻧﻴﺔ ﺍﻟﻨﺴﺨﺔ ﻫﺬﻩ .ﻭﺍﻟﻤﺤﻔﻮﻇﺎﺕ ﺍﻟﻤﻜﺘﺒﺔ ﻗﺴﻢ ﻓﻲ ﺍﻟﻤﺘﻮﻓﺮﺓ ﺍﻟﻮﺛﺎﺋﻖ ﺿﻤﻦ ﺃﺻﻠﻴﺔ ﻭﺭﻗﻴﺔ ﻭﺛﻴﻘﺔ ﻣﻦ ﻧﻘﻼ ً◌ 此电子版(PDF版本)由国际电信联盟(ITU)图书馆和档案室利用存于该处的纸质文件扫描提供。 Настоящий электронный вариант (PDF) был подготовлен в библиотечно-архивной службе Международного союза электросвязи путем сканирования исходного документа в бумажной форме из библиотечно-архивной службы МСЭ. © International Telecommunication Union XVII A.R DUSSGLDORF 21.5 - 1.6 1990 CCIR XVIIth PLENARY ASSEMBLY DUSSELDORF, 1990 INTERNATIONAL TELECOMMUNICATION UNION QUESTIONS OF THE CCIR, 1990 VOLUME XV SG 1 SPECTRUM MANAGEMENT TECHNIQUES SG 12 INTER-SERVICE SHARING AND COMPATIBILITY SG 5 RADIO WAVE PROPAGATION IN NON-IONIZED MEDIA SG 6 RADIO WAVE PROPAGATION IN IONIZED MEDIA SG 7 SCIENCE SERVICES INTERNATIONAL RADIO CONSULTATIVE COMMITTEE Geneva, 1990 CCIR 1. The International Radio Consultative Committee (CCIR) is the permanent organ of the International Telecommunication Union responsible under the International Telecommunication Convention "... to study technical and operating questions relating specifically to radiocommunications without limit of frequency range, and to issue recommendations on them../7 (Inter national Telecommunication Convention, Nairobi 1982, First Part, Chapter I, Art. -
Build Your Own Low-Power Transmitters: Projects for the Electronics Experimenter
Build Your Own Low-Power Transmitters Projects for the Electronics Experimenter This Page Intentionally Left Blank Build Your Own Low-Power Transmitters Projects for the Electronics Experimenter Rudolf F. Graf William Sheets Boston Oxford Auckland Johannesburg Melbourne New Delhi Newnes is an imprint of Butterworth–Heinemann. Copyright © 2001 Rudolf F. Graf and William Sheets A member of the Reed Elsevier group All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or trans- mitted in any form or by any means, electronic, mechanical, photocopying, record- ing, or otherwise, without the prior written permission of the publisher. Recognizing the importance of preserving what has been written, Butterworth– Heinemann prints its books on acid-free paper whenever possible. Butterworth–Heinemann supports the efforts of American Forests and the Global ReLeaf program in its campaign for the betterment of trees, forests, and our environment. Library of Congress Cataloging-in-Publication Data Graf, Rudolf F. Build your own low-power transmitters : projects for the electronics experimenter / Rudolf F. Graf, William Sheets. p. cm. ISBN 0-7506-7244-7 (alk. Paper) 1. Radio—Transmitters and transmission—Design and construction— Amateurs’ manuals. 2. Low voltage systems—Designs and construction— Amateurs’ manuals. I. Sheets, William. II. Title. TK6561 .G67 2001 621 .384’131—dc21 2001030550 British Library Cataloguing-in-Publication Data A catalogue record for this book is available from the British Library. The publisher offers special discounts on bulk orders of this book. For information, please contact: Manager of Special Sales Butterworth–Heinemann 225 Wildwood Avenue Woburn, MA 01801-2041 Tel: 781-904-2500 Fax: 781-904-2620 For information on all Newnes publications available, contact our World Wide Web home page at: http://www.newnespress.com.