 | Radio and Electronics (DED Philippinen, 66 p.) |
 |  | (introduction...) |
|  | 1. INTRODUCTION |
| | (introduction...) |
| | 1.1. A TRIAL TO STATE A DEFINITION OF ELECTRONICS |
| | 1.2. A SHORT HISTORY OF ELECTRONICS |
| | 1.3. CLASSIFICATION OF ELECTRONIC DEVICES |
| | 2. PRINCIPLES OF RADIO COMMUNICATION UNICATION |
| | 2.1. BASICAL IDEAS ABOUT COMMUNICATION |
| | 2.2. DEVELOPMENT OF LONG DISTANCE COMMUNICATION |
| | 2.3. FIDELITY AND DISTORTION |
| | 3. TRANSDUCERS |
| | (introduction...) |
| | 3.1. MICROPHONES |
| | 3.2. LOUDSPEAKERS |
| | 3.3. THE TELEPHON SYSTEM |
| | 3.4. PROBLEM OF FREQUENCY RANGES |
| | 3.5. BANDWIDTH |
| | 4. RADIOWAVES |
| | (introduction...) |
| | 4.1. ORIGIN OF RADIOWAVES |
| | 4.2. PARAMETERS OF ELECTROMAGNETIC WAVES |
| | 4.3. PROPAGATION OF RADIOWAVES |
| | 4.4. SPECTRUM OF RADIOWAVES AND BANDS OF RADIOWAVES |
| | 5. MODULATION OF RADIOWAVES |
| | (introduction...) |
| | 5.1. THE AMPLITUDE MODULATION (AM) |
| | 5.2. FREQUENCY MODULATION (FM) |
| | 5.3. SIDEBANDS |
| | 5.4. TRANSMISSION OF RADIOSIGNALS |
| | 6. RECEPTION OF RADIOSIGNALS (AM - TYPE) |
| | 6.1. AERIAL |
| | 6.2. THE TUNED CIRCUIT |
| | 6.3. INCIDENTAL REMARK ON BLOCK DIAGRAMS |
| | 6.4. DETECTOR OR DEMODULATOR |
| | 6.5. POWER SUPPLY |
| | 6.6. AMPLIFIER |
| | 6.7. SUPERHET RECEIVER (the SUPER) |
| | 6.8 INCIDENTAL REMARK ON MIXING FREQUENCIES |
| | 6.9. CONSTRUCTION OF A SUPERHETRADIO |
| | 7. COMPONENTS OF MODERN RADIO RECEIVERS |
| | 7.1.1. HANDLING OF ELECTRONIC COMPONENTS |
| | 7.1.2. HANDLING OF PRINTED CIRCUITS |
| | 7.1.3. DIFFERENTIATION OF COMPONENTS |
| | 8. PASSIVE COMPONENTS |
| | 8.1. RESISTORS ELECTRICAL CHARACTERISTICS |
| | 8.2. CAPACITORS |
| | 8.3. INDUCTORS |
| | 8.4. COMBINATION OF PASSIVE COMPONENTS |
| | 8.4.1. SERIES CONNECTION OF R AND C, OR R AND L |
| | 8.4.2. COMBINATION OF L AND C, RESONANT (TUNED) CIRCUITS |
| | 8.4.3. TUNED CIRCUIT CONNECTED TO AN AC-VOLTAGE |
| | (introduction...) |
| | 8.4.4.1. QUALITY OF TUNED CIRCUITS |
| | 8.4.4.2. BANDWIDTH |
| | 9. ACTIVE COMPONENTS -1- DIODES |
| | 9.1. CHARACTERISTICS OF SEMICONDUCTORS |
| | 9.2. THE PN-JUNCTION OR DIODE |
| | (introduction...) |
| | 9.2.1. PN-JUNCTION CONNECTED TO VOLTAGE |
| | 9.2.2. CHARACTERISTICS OF A PN-JUNCTION OR DIODE |
| | 9.2.3. ZENERDIODE |
| | 10. BLOCKS OF RADIOS / -1- / POWER SUPPLIES |
| | 10.1. GENERAL CONSIDERATIONS |
| | 10.2. TRANSFORMER |
| | 10.3. THE RECTIFIERS. |
| | 10.4. SMOOTHING AND FILTER CIRCUITS |
| | 10.4.1. THE RESERVOIR CAPACITOR |
| | 10.4.2. FILTER CIRCUITS |
| | 10.5. STABILIZATION |
| | 10.5.1. GENERAL REMARKS |
| | 10.5.1.1. LOAD VARIATIONS |
| | 10.5.1.2. INTERNAL RESISTANCE OF VOLTAGESOURCES |
| | 10.5.1.3. PROBLEMS CAUSED BY THE SMOOTHING CIRCUIT |
| | 10.5.5. METHODS OF STABILIZATION |
| | (introduction...) |
| | 10.5.5.1. PARALLEL-STABILIZATION |
| | 10.5.2.2. SERIES STABILIZATION |
| | 11. ACTIVE COMPONENTS -2- / TRANSISTORS |
| | 11.1. CONSTRUCTION OF A TRANSISTOR |
| | 11.2. CHARACTERISTICS OF TRANSISTORS |
| | (introduction...) |
| | 11.2.1 HANDLING OF CHARACTERISTICS OF TRANSISTORS |
| | 11.2.1.1. CONSTRUCTION OF THE STATIC-MUTUAL-CHARACTERISTICS |
| | 11.2.1.2. CONSTRUCTION OF THE DYNAMIC MUTUAL CHARACTERISTICS |
| | 11.2.1.3. CONSTRUCTION OF THE MAXIMUM-POWER-LINE |
| | 12. AMPLIFIERS |
| | (introduction...) |
| | 12.1. STRUCTURE OF A CLASS A AMPLIFIER |
| | 12.2. FUNCTION OF A SIMPLE CLASS A AMPLIFIER |
| | 12.3. ADVANCED CLASS A AMPLIFIER |
| | 12.4. STABILIZATION OF THE QUIESCENT VOLTAGE |
| | 13. CLASS B AMPLIFIERS |
| | 13.1. LIMITS OF CLASS A AMPLIFIERS |
| | 13.2. CLASS B AMPLIFIERS WITH TRANSFORMERS |
| | 13.3. CLASS B AMPLIFIERS WITHOUT TRANSFORMERS |
| | 13.4. POWER AMPLIFIER WITH COMPLIMENTARY TRANSISTORS. |
| | 14. DETECTOR OR DEMODULATOR |
| | 15. AGC-AUTOMATIC GAIN CONTROL |
| | 16. IF-AMPLIFIERS |
| | 17. FEEDBACK |
| | 18. OSCILLATORS |
| | 19. FREQUENCY CHANGERS MIXERSTAGE |
| | 20. DECOUPLING CIRCUITS |
| | 21. MATCHING OF AMPLIFIERSTAGES |
| | 22. COUPLING OF AMPLIFIERSTAGES |
| | 23. RADIO SERVICING |
| | 23.1. IMPORTANCE AND SUBJECT OF FAULT FINDING |
| | 23.2. FAULTS AND FAULT FINDING |
| | 23.3. FAULT FINDING METHODS |
| | 24. THE USE OF THE OSCILLOSCOPE |
7.1.1. HANDLING OF ELECTRONIC COMPONENTS
If you open a modern radio receiver, you will find, that all its components are extremely small. This is because the buyers of those radios want them to be as light as possible and the producers are trying to built them as cheap as possible.
To have light and small radios is on the one hand a big advantage. But on the other hand the tiny components, necessary for such small radios cause three major problems which you have to cope with if you want to repair this kind of radios instead of destroying them:
- small components have also a small mass. Small masses are heated up very easily. Most electronic components unfortunately are easily spoilt if they are heated up to much. Therefore while soldering in such radios you have always to take care,
- that the soldering iron is fitting for the job (as smaller the component, as smaller the iron).- that the soldering tin is fitting for the job (thin tin takes less time to get molten)
- that you never heat up the soldering point longer than necessary to limit the heat energy flowing to it, or
- if it is not possible to avoid heat, to cool the soldered terminal down by holding it by a pair of plier or touching it thoroughly with a screwdriver.
- small components have mostly very thin terminmalwires too, so you should always be extremly careful when bending or pulling any component in such a radio.- on an extremly small component you cannot write down any specifications. In order to enable you to find specification even though, there are used special colour codes. Generally you should not rub away any colour or letter on such a component. It might be you need this part of the specifications to repair the device properly.
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