|Radio and Electronics (DED Philippinen, 66 p.)|
|11. ACTIVE COMPONENTS -2- / TRANSISTORS|
|11.2. CHARACTERISTICS OF TRANSISTORS|
|11.2.1 HANDLING OF CHARACTERISTICS OF TRANSISTORS|
If the transistor is connected in a circuit the mutual characteristics changes according to the parameters given in this very circuit. The graph, showing this characteristics, is called the DYNAMIC MUTUAL CHARACTERISTICS and it shows actually the ability of amplifications of this very circuit.
To construct it, we enter the loadline of the collector-resistor into the output quadrant and find the values of the collector-current for each given base-current. The relation Ic/Ib is represented then in the 2. quadrant as shown in fig. 133.
For the given circuit of a transistor with the given characteristics, an Rc of 300 Ohms and a supply voltage of 9 Volts, we find that the amplification is rather constant as long as the base-current does not exceed 3 mA. Above this value the amplification is decreased down to 0.
Mind too, that the output voltage Vce is high at low base-currents (low-input-signal) and vice versa.