33
Circuit 8:
Determining the connection sequence of a NPN transistor
Setup information
Install the transistor as shown in
Fig. 2.8
. After that, install all other resistors. Now it is time for the jump-
ers. For the purpose of identification, the measuring leads are shown in the figure in black or red. Feel free
to use your own colours. Then connect the moving-coil instrument. Check the placement on the board again
and only then connect the battery.
Components required:
1 x 2N3904 transistor,
1 x 470
Ω
resistor,
2 x 1 k
Ω
resistors,
2 x 10 k
Ω
resistors,
1 x moving-coil instrument,
1 x breadboard, 1 x 9V bat-
tery with clip connector
Fig. 2.8:
Determining the connec-
tion sequence of a NPN transistor
Experiment
Connect the red line first. Then with the black line touch the remaining two transistor terminals one after
the other. Repeat this until the red line connection is located at the terminal of the other two transistor
connections where the moving-coin instrument measures the greater voltage deflection. All other connec-
tion combinations should show a smaller deflection on the meter; if this is not happening, the transistor is
faulty. The red line indicates the base connection of an NPN transistor.
This method works with silicon and germanium transistors, but only with bipolar transistors and not with
FET transistors.
The circuit diagram for this experiment is shown in Chap. 3, Fig. 3.8.
Содержание ELECTRONICS EXPERIMENTS BOX
Страница 4: ......
Страница 251: ...253 Fig 3 27 Circuit 27 4 seconds switch off delay Fig 3 28 Circuit 28 20 seconds switch off delay...
Страница 258: ...260 Fig 3 42 Circuit 42 Active 8 5V battery monitor Fig 3 43 Circuit 43 Active 7 8V battery monitor...
Страница 260: ...262 Fig 3 46 Circuit 46 Meters for 1 5 V Zener diodes and higher Fig 3 47 Circuit 47 Discreet 2 2V Zener diode...
Страница 261: ...263 Fig 3 48 Circuit 48 Discreet 2 9V Zener diode Fig 3 49 Circuit 49 Discreet 3 7V Zener diode...
Страница 265: ...267 Fig 3 56 Cir cuit 56 Audio limiter Fig 3 57 Circuit 57 Amplifier for a storm detector...
Страница 269: ...271 Fig 3 64 Circuit 64 Stabilizer for 1 9 V Fig 3 65 Circuit 65 Stabilizer for 2 5 V...
Страница 275: ...277 Fig 3 80 Circuit 80 Quiztimer 30 seconds Fig 3 81 Circuit 81 Handy diode tester...
Страница 290: ...292 Fig 3 118 Circuit 118 HF watch dog with LED indicator Fig 3 119 Circuit 119 HF watchdog with moving coil instrument...
Страница 295: ...297 Fig 3 130 Circuit 130 4 seconds switch on delay Fig 3 131 Circuit 131 15 seconds switch off delay...
Страница 298: ...300 Fig 3 136 Circuit 136 NAND gate with moving coil instrument Fig 3 137 Circuit 137 Input level Mixing console...
Страница 300: ...302 Fig 3 140 Circuit 140 Electrometer with moving coil instrument Fig 3 141 Circuit 141 Simple AM Radio...
Страница 315: ...317 Fig 3 179 Circuit 179 HF generator 150 kHz Fig 3 180 Circuit 180 HF generator 420 kHz...
Страница 324: ...326 Fig 3 202 Circuit 202 3 seconds switch on delay Fig 3 203 Circuit 203 7 seconds switch on delay...
Страница 325: ...327 Fig 3 204 Circuit 204 Piercing siren sound with Piezo element Fig 3 205 Circuit 205 Discrete Operational ampli fier...
Страница 328: ...330 Fig 3 210 Circuit 210 Discreet 5 2V Zener diode Fig 3 211 Circuit 211 Discreet 7 4V Zener diode...
