Radio and electronics cookbook

Radio and Electronics Cookbook

Radio and Electronics Cookbook
Edited by Dr George Brown, CEng, FIEE, M5ACN

OXFORD

AUCKLAND BOSTON JOHANNESBURG MELBOURNE NEW DELHI

Newnes An imprint of Butterworth-Heinemann Linacre House, Jordan Hill, Oxford OX2 8DP 225 Wildwood Avenue, Woburn, MA 01801-2041 A division of Reed Educational and Professional Publishing Ltd A member of the ReedElsevier plc group First published 2001 © Radio Society of Great Britain 2001
All rights reserved. No part of this publication may be reproduced in any material form (including photocopying or storing in any medium by electronic means and whether or not transiently or incidentally to some other use of this publication) without the written permission of the copyright holder except in accordance with theprovisions of the Copyright, Designs and Patents Act 1988 or under the terms of a licence issued by the Copyright Licensing Agency Ltd, 90 Tottenham Court Road, London, England W1P 0LP. Applications for the copyright holder’s written permission to reproduce any part of this publication should be addressed to the publishers

British Library Cataloguing in Publication Data A catalogue record forthis book is available from the British Library ISBN 0 7506 5214 4

RSGB Lambda House Cranborne Road Potters Bar Herts EN6 3JE

Composition by Genesis Typesetting, Laser Quay, Rochester, Kent Printed and bound in Great Britain

Contents

Preface 1. A medium-wave receiver 2. An audio-frequency amplifier 3. A medium-wave receiver using a ferrite-rod aerial 4. A simple electronic organ 5.Experiments with the NE555 timer 6. A simple metronome 7. What is a resistor? 8. Waves – Part 1 9. A beat-frequency oscillator 10. What is a capacitor? 11. Waves – Part 2 12. An LED flasher 13. Waves – Part 3 14. Choosing a switch 15. An aerial tuning unit for a receiver 16. A simple 2 m receiver preamplifier 17. Receiving aerials for amateur radio 18. The Colt 80 m receiver – Part 1 19. A crystalradio receiver 20. The varactor (or varicap) diode 21. A portable radio for medium waves 22. The Colt 80 m receiver – Part 2

ix 1 4 9 12 17 21 24 27 31 34 38 41 44 46 49 52 54 58 62 64 65 70 v

Contents

23. A simple transistor tester 24. An introduction to transmitters 25. The Colt 80 m receiver – Part 3 26. A two-way Morse practice system 27. The Colt 80 m receiver – Part 4 28. A simplecrystal set 29. A crystal calibrator 30. A simple short-wave receiver – Part 1 31. A fruit-powered medium-wave radio 32. A capacitance bridge 33. A simple short-wave receiver – Part 2 34. A basic continuity tester 35. A charger for NiCad batteries 36. An 80 metre crystal-controlled CW transmitter 37. A solar-powered MW radio 38. A receiver for the 7 MHz amateur band 39. Diodes for protection 40. AnRF signal probe 41. An RF changeover circuit 42. A low-light indicator 43. A J-pole aerial for 50 MHz 44. Measuring light intensity – the photometer 45. A 70 cm Quad loop aerial 46. A UHF field strength meter 47. Christmas tree LEDs 48. An audio signal injector 49. Standing waves 50. A standing-wave indicator for HF 51. A moisture meter 52. Simple aerials 53. A breadboard 80 cm CW transmitter vi73 77 81 88 91 95 100 104 106 109 113 117 119 123 129 133 137 140 142 146 149 153 156 160 162 166 168 170 174 177 182

Contents

54. A 7-element low-pass filter for transmitters 55. Radio-frequency mixing explained 56. A voltage monitor for a 12 V power supply 57. A 1750 Hz toneburst for repeater access 58. A circuit for flashing LEDs 59. Digital logic circuits 60. A resistive SWR indicator61. An audio filter for CW 62. An electronic die 63. The absorption wavemeter 64. An HF absorption wavemeter 65. A vertical aerial for 70 cm 66. A UHF corner reflector aerial 67. A switched dummy load 68. A simple Morse oscillator 69. A bipolar transistor tester 70. The ‘Yearling’ 20 m receiver 71. Adding the 80 metre band to the Yearling receiver 72. How the Yearling works 73. A field strength...