Chapter 1 Background of the Project
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Signal Issue 37
Signal Issue 37 Tricks of the Trade Dave Porter G4OYX and Alan Beech G1BXG By 25th September 1965, Radio 390 was on the air and 31st December 2015 marks the fiftieth anniversary of the start of the offshore station Radio Scotland. The only remaining station to launch with RCA 10 kW Ampliphase transmitters was Radio 270 from 4th June 1966, on-air some three months later than originally planned. Member’s contribution understood that, whilst CE was used to these T-K arrangements, mainly for Government contracts, the need After reading the last three ToTT, VMARS Member Tony to effect a quick turn-around with minimal delays was not Rock G3KTR/AD1X contacted the author (DP) with the quite their norm. With time slipping by, the decision was following information on the 1965 build of Radio Scotland. made to leave the USA without the systems being totally commissioned and to complete en-route. Also, during this Tony writes; I read with interest the article you and Alan trip, it was discovered that one of the planned operating put together on Ampliphase transmitters. In the mid-1960s frequencies, namely 650 kHz, was actually occupied in the I was working out of the RCA Broadcast & UK by a certain high-power station on 647 kHz, the Communications Division at Sunbury-on-Thames. At this 150 kW BBC Third Programme. It was understood that an time RCA had sold several transmitters to offshore ‘pirate’ early ‘recce’ by the Americans to the UK to check for ‘spare radio stations. While Marconi and other European channels’ resulted in a monitoring time when the Third companies could be subjected to sanctions by the Programme was not scheduled on air. -
Understanding the Cavity Duplexer
i THE CAVITY DUPLEXER John E Portune W6NBC [email protected] rev 2019 NOTE FROM AUTHOR This book was written several years ago and based on hardware-store copper water pipe as the source of home-brew duplexer construction materials. Later I began making from spun-aluminum commercial cake pans. Both require no welding. Unfortunately the price of copper is today much higher. Cake pans, however, are still reasonably priced, readily available and very acceptable as the basis especially for VHF cavities. Because of maximum cavity size limit, copper water pipe may still be indicated for UHF and above. In any case, how a duplexer operates is basic physics. No matter what the material, or whether the duplexer is commercial or home brew, the principles herein are universal to duplexer construction, modification and tuning. This book, however, is not finished. Repeater building is no longer my primary interest in ham radio. Some subjects could be added. But as it contains the essentials, I have placed on the internet incomplete. If you reproduce it, be so kind as to give proper author’s credits. W6NBC January 2019 . ii CHAPTER OUTLINE 1. The Mysterious Duplexer • The black box everybody uses but nobody understands • Keys to understanding it • This is not a cookbook 2. Let’s Make a Cavity • Home-brew 2M aluminum cavity • Example for the entire book • The best way to learn 3. Cavities • Mechanical and electrical properties of cavities • Basic structure of a duplexer • Why use cavities • Getting energy in and out: loops, probes, taps and ports • Three cavity types: Bp, Br, Bp/Br • Creating the other types • Helical resonators for 6M and 10M duplexers 4. -
A Guide for Radio Operators BROCHURE RADIO TRANSM ANG 3/27/97 8:47 PM Page 2
BROCHURE RADIO TRANSM ANG 3/27/97 8:47 PM Page 17 A Guide for Radio Operators BROCHURE RADIO TRANSM ANG 3/27/97 8:47 PM Page 2 Aussi disponible en français. 32-EN-95539W-01 © Minister of Public Works and Government Services Canada 1996 BROCHURE RADIO TRANSM ANG 3/27/97 8:47 PM Page 3 CUTTING THROUGH... INTERFERENCE FROM RADIO TRANSMITTERS A Guide for Radio Operators This brochure is primarily for amateur and General Radio Service (GRS, commonly known as CB) radio operators. It provides basic information to help you install and maintain your station so you get the best performance and the most enjoyment from it. You will learn how to identify the causes of radio interference in nearby electronic equipment, and how to fix the problem. What type of equipment can be affected by radio interference? Both radio and non-radio devices can be adversely affected by radio signals. Radio devices include AM and FM radios, televisions, cordless telephones and wireless intercoms. Non-radio electronic equipment includes stereo audio systems, wired telephones and regular wired intercoms. All of this equipment can be disturbed by radio signals. What can cause radio interference? Interference usually occurs when radio transmitters and electronic equipment are operated within close range of each other. Interference is caused by: ■ incorrectly installed radio transmitting equipment; ■ an intense radio signal from a nearby transmitter; ■ unwanted signals (called spurious radiation) generated by the transmitting equipment; and ■ not enough shielding or filtering in the electronic equipment to prevent it from picking up unwanted signals. What can you do? 1. -
Digiton Systems
RESULTS OF THE DRM SIMULCAST FIELD TRIAL IN FM BAND IN THE RUSSIAN FEDERATION June to December 2019 Sergei Sokolov Sergei Myshyanov Digiton Systems Version 3, 2020-12-07 0. Abstract Digiton Systems carried out a high-power field trial of the DRM system in DRM Simulcast mode by order of the Russian Television and Radio Broadcasting Network (RTRN) in the FM band in the Saint-Petersburg city, in the Russian Federation during June to December 2019. The DRM Consortium members RFmondial GmbH and Fraunhofer IIS contributed their expertise to the trial to enable the system to be tested in a real commercial environment with a wide variety of reception conditions. RTRN provided financing for the trial. Digiton Systems provided equipment, project management and measuring effort for the trial. Triada TV provided the transmitter. European Media Group (EMG) company and GPM Radio company allowed to launch a digital DRM signal between their FM radio stations Studio 21 at 95.5 MHz and Comedy Radio at 95.9 MHz. Radio Studio 21 is a part of EMG and Comedy Radio is a part of GMP Radio. During the trial the existing transmitter infrastructure was used, without any changes in other broadcasted stations. The DRM signal was added to the combiner infrastructure, already combining more than a dozen analogue FM services onto a single antenna. This document describes the trial and results. Additional key words: DRM, Digital Radio Mondiale, FM-band, VHF band-II, DRM-FM, DRM Simulcast, FM Combiner 2 1. Location and environment for the trial The trial was conducted in the Northwest region of Russian Federation from the Leningrad radio and television broadcasting center located just to the center of the city of Saint- Petersburg. -
Implementation Considerations for the Introduction and Transition to Digital Terrestrial Sound and Multimedia Broadcasting
Report ITU-R BS.2384-0 (07/2015) Implementation considerations for the introduction and transition to digital terrestrial sound and multimedia broadcasting BS Series Broadcasting service (sound) ii Rep. ITU-R BS.2384-0 Foreword The role of the Radiocommunication Sector is to ensure the rational, equitable, efficient and economical use of the radio- frequency spectrum by all radiocommunication services, including satellite services, and carry out studies without limit of frequency range on the basis of which Recommendations are adopted. The regulatory and policy functions of the Radiocommunication Sector are performed by World and Regional Radiocommunication Conferences and Radiocommunication Assemblies supported by Study Groups. Policy on Intellectual Property Right (IPR) ITU-R policy on IPR is described in the Common Patent Policy for ITU-T/ITU-R/ISO/IEC referenced in Annex 1 of Resolution ITU-R 1. Forms to be used for the submission of patent statements and licensing declarations by patent holders are available from http://www.itu.int/ITU-R/go/patents/en where the Guidelines for Implementation of the Common Patent Policy for ITU-T/ITU-R/ISO/IEC and the ITU-R patent information database can also be found. Series of ITU-R Reports (Also available online at http://www.itu.int/publ/R-REP/en) Series Title BO Satellite delivery BR Recording for production, archival and play-out; film for television BS Broadcasting service (sound) BT Broadcasting service (television) F Fixed service M Mobile, radiodetermination, amateur and related satellite services P Radiowave propagation RA Radio astronomy RS Remote sensing systems S Fixed-satellite service SA Space applications and meteorology SF Frequency sharing and coordination between fixed-satellite and fixed service systems SM Spectrum management Note: This ITU-R Report was approved in English by the Study Group under the procedure detailed in Resolution ITU-R 1. -
Sdt303um Analog/Digital Tv Transmitter
Screen Service SDT 303UM SDT303UM ANALOG/DIGITAL TV TRANSMITTER CONTENTS 1 INTRODUCTION ..................................................................................................................................... 2 2 EQUIPMENT COMPOSITION ................................................................................................................. 2 2.1 SINGLE AND DUAL DRIVER CONFIGURATION ............................................................................ 2 3 SCA 202UB ............................................................................................................................................. 5 4 SDT MAGNUM (See Relevant Manual) ................................................................................................. 15 4.1 CONTROL UNIT ............................................................................................................................. 15 4.2 POWER DISTRIBUTION UNIT ....................................................................................................... 16 4.3 OUTPUT COMBINER & DUMMY LOAD ........................................................................................ 16 4.4 OUTPUT DIRECTIONAL COUPLER .............................................................................................. 16 4.5 OUTPUT FILTER ........................................................................................................................... 16 5 TECHNICAL SPECIFICATIONS ........................................................................................................... -
Consultation Document Spectrum Allocation Strategy for Other Radio
FOREWORD Botswana Telecommunications Authority (BTA) is mandated by the Telecommunication Act, 1996 [No. 15 of 1996] to ensure the rational use of the radio frequency spectrum in Botswana. The BTA assisted by the Teleplan AS from Norway in association with ICT Consultants (Pty) Ltd from Botswana, is in the process of developing a comprehensive Spectrum Management Strategy. The spectrum management strategy has the following components: • Review the current national radio frequency plan; • Develop a spectrum allocation strategy for various radio services; • Develop a spectrum licensing policy for various frequency bands; and • Develop a spectrum pricing policy In January 2007, the BTA issued a consultation document for radio services dealing with preliminary views and recommendations relating to high demand spectrum . A workshop was held on 14 – 15 February 2007, during which the consultation document was presented and comments/input received from stakeholders. The consultation process for the high demand spectrum has been finalised and the BTA has already communicated it to the industry stakeholders. This consultation document contains information and recommendations on other radio services that were not included in the first round of consultation. The document summarises the key findings from technology reviews, analysis of regional radio regulations, frequency plans (national, regional and international) and available radio equipment. Page 1 of 80 The Authority wishes to invite the industry stakeholders, (the operators, service providers, -
Long-Wave and Medium-Wave Propagation
~EMGINEERING TRAINING SUPPLEMENT No. 10 LONG-WAVE AND MEDIUM-WAVE PROPAGATION BRITISH BROADCASTING CORPORATION LONDON 1957 ENGINEERING TRAINING SUPPLEMENT No. 10 LONG-WAVE AND MEDIUM-WAVE PROPAGATION Prepared by the Engineering Training Department from an original manuscript by H. E. FARROW, Grad.1.E.E. Issued by THE BBC ENGINEERING TRAINING DEPARTMENT 1957 ACKNOWLEDGMENTS Fig. 2 is based upon a curve given by H. P. Williams in 'Antenna Theory and Design', published by Sir Isaac Pitrnan and Sons Ltd. Figs. 5, 6, 7, 8 and 9 are based upon curves prepared by the C.C.I.R. CONTENTS ACKNOWLEDGMENTS... ... INTRODUCTION ... ... ... AERIALS ... ... ... ... GROUND-WAVEPROPAGATION ... GEOLOGICALCORRELATION ... PROPAGATIONCURVES ... ... RECOVERYAND LOSS EFFECTS ... MIXED-PATHPROPAGATION ... SYNCHRONISED. GROUP WORKING LOW-POWERINSTALLATIONS ... IONOSPHERICREFLECTION ... FADING ... ... ... ... REDUCTIONOF SERVICEAREA BY SKYWAVE ... LONG-RANGEINTERFERENCE BY SKYWAVE ... APPENDIXI ... ... ... ... ... REFERENCES ... ... ... ... ... LONG-WAVE AND MEDIUM-WAVE PROPAGATION The general purpose of this Supplement is to explain the main features of propagation at low and medium frequencies i.e. 30-3000 kc/s, and in particular in the bands used for broadcasting viz. 150-285 kc/s and 525-1605 kc/s. In these bands, the signal at the receiver may have two components: they are (a) a ground wave, i.e. one that follows ground contours (b) an ionspheric wave (sky wave) which is reflected from an ionised layer under certain conditions. In the vicinity of the transmitter, the ground wave is the predominant component, and for domestic broadcasting, the service ideally would be provided by the ground wave only. In fact the limit to the service area is often set by interference from the sky wave. -
WBU Radio Guide
FOREWORD The purpose of the Digital Radio Guide is to help engineers and managers in the radio broadcast community understand options for digital radio systems available in 2019. The guide covers systems used for transmission in different media, but not for programme production. The in-depth technical descriptions of the systems are available from the proponent organisations and their websites listed in the appendices. The choice of the appropriate system is the responsibility of the broadcaster or national regulator who should take into account the various technical, commercial and legal factors relevant to the application. We are grateful to the many organisations and consortia whose systems and services are featured in the guide for providing the updates for this latest edition. In particular, our thanks go to the following organisations: European Broadcasting Union (EBU) North American Broadcasters Association (NABA) Digital Radio Mondiale (DRM) HD Radio WorldDAB Forum Amal Punchihewa Former Vice-Chairman World Broadcasting Unions - Technical Committee April 2019 2 TABLE OF CONTENTS INTRODUCTION .......................................................................................................................................... 5 WHAT IS DIGITAL RADIO? ....................................................................................................................... 7 WHY DIGITAL RADIO? .............................................................................................................................. 9 TERRESTRIAL -
Txud1000atsc Uhf Tv
TXUD1000/ATSC UHF TV Transmitter CODE APT205L/DIG TITLE TXUD1000/ATSC UHF TV TRANSMITTER REV 1 DATE 03/08/09 Registration number: IT-17686 SS 96 Km 113 70027 Palo del Colle (Ba) ITALY Tel. +39 (0)80 626755 Fax +39 (0)80 629262 Registration number: IT-24436 E-mail: [email protected] Web site: http://www.elettronika.it WARNING The apparatus described in this manual has been designed and manufactured with devices to safe- guard the users. In any case it is recommended that during any operation of installation, maintenance, miscellaneous interventions and calibrations requiring the apparatus to be switched on, THE USER TAKES ALL THE PRECAUTIONS AGAINST INCIDENTS It is required to use the proper clothes and protection gloves in order to prevent damages from inci- dental contacts with high-voltage parts. The manufacturer declines every responsibility in case the recommendations above are not followed. IMPORTANT The component lists attached to the relevant electrical diagrams indicate for each item the reference, the description and the type normally used. The Elettronika S.r.l. though reserves the right to use or supply as spare parts components with equivalent characteristics but of a different type, assuring anyway the optimal work of the apparatus in accordance with the specifications. The enclosed monographs are solely owned by Elettronika S.r.l. The use of anything enclosed in this technical manual without explicit authorization given by Elettronika S.r.l. will be prosecuted by the law. The data and technical characteristics of the apparatus described in this manual are not compelling for the manufacturer. -
Technical Service Bulletin 041029
Technical Service Bulletin 041029 Technical Service Bulletin 041029 Glossary of Terms: Optimum and Ultimate Digital This service bulletin provides a glossary of terms for the Optimum and Ultimate series of digital television transmitters. If there are additional terms you would like to see included in this glossary, please send your suggestions to [email protected]. Term Definition Comment 8-VSB Eight-level vestigial sideband The modulation format used in the ATSC digital television system. In the context of the ADAPT exciter, the input module of the exciter used to convert the incoming transport stream to 8-VSB modulation. Affichage Display French term. e.g. Carte Affichage = display card w/ bargraphs behind control panel. AGC Automatic gain control System to automatically maintain the transmitter RF output at a predefined power level. Aire Air French term. ALE Adaptive Linear Equalizer Synonymous with linear corrector in ADAPT exciter. Corrector affecting ATSC signal to noise (or EVM). Alimentation (ALIM) Power supply French term. Ampli Amplifier Abbreviated term. Amplificateur Amplifier French term. Analogique Analog French term. Armoire Cabinet French term. ATSC Advanced Television System A digital television system utilizing the 8-VSB modulation format. Committee Baie Bay French term. e.g. amplifier bay. Bande Passante Passband French term. Bas / Baisse Low French term. Base, (__ de base) Basic, baseline French term. The most basic or generic version of an item. BI (Bde I) Band I, VHF low band. Abbreviation (approx 54-88 MHz) BIII (Bde III) Band III, VHF high band. Abbreviation. (approx 174-216 MHz) BIV & BV (Bde iV/V) Bands IV and V, UHF TV band. -
The HEATHKIT HN-31 CANTENNA
NOTES on the HEATHKIT HN-31 CANTENNA HISTORY CONSTRUCTION ALL ABOUT THE RESISTOR SOURCES of SUPPLY OIL and HEAT PROPERTIES PERFORMANCE MEASUREMENTS by John White VA7JW FEBRUARY 2012 © Revision 1 NOTES on the HEATHKIT HN-31 CANTENNA HISTORY The Heathkit HN-31 sold between 1961 and 1983 for $9.95 as a 50 ohm dummy load without cooling oil; that was not included! The task of sourcing the appropriate oil fell to the buyer to purchase. Chuck Pensions book1 estimates that sales of the HN-31 were in the order of 200,000 units between 1961 and 1972. He further states that “The Cantenna RF Load is undeniably the longest running, most successful product Heath ever made”. One might have to agree since the MFJ-250 and Vectronic’s ALD-1500 are of a similar design and are still offered today. The author purchased the HN-31 model in 1968. The oil used is Heathkit recommended white mineral oil purchased from a pharmacy and is of medicinal / food grade quality. The other oil option is transformer oil, but it is more difficult to source. The dummy load has been used for many years and remains in apparent excellent condition. The resistance measures 49.4 ohms DC, the oil is visually clear, there is no evidence of contamination by water or rust or any other particulate matter, and the paint pail is mechanically sound. Figure 1 HN-31 Manual Excerpts dated 11 / 26 / 65 Reference 1 at End of Article HEATHKIT HN-31 INTERNAL CONSTRUCTION For those unfamiliar with the construction of the HN-31, some of the manual assembly diagrams are reproduced here.