71
Circuit 46:
Meters for 1.5 V Zener diodes and higher
Setup information
Install the two transistors and the three resistors as shown in
Fig. 2.46.
The seven jumper wires come next.
Last but not least connect the moving-coil instrument. Check the placement on the board again and only
then connect the battery.
Components required:
2 x 2N3904 transistors,
1 x 220
Ω
resistor,
1 x 2.2 k
Ω
resistor,
1 x 4.7 k
Ω
resistor,
1 x moving-coil instrument,
1 x breadboard, 1 x 9V bat-
tery with clip connector
Fig. 2.46:
Meters for 1.5 V Zener
diodes and higher
Experiment
The Zener diode meter shows the Zener voltage of a properly functioning Zener diode on the moving-coil
meter.
Please note: Zener diodes are connected in the reverse direction!
Look for Zener diodes in your crafting box. If you find one within the voltage range of 1.5V to 4.3V, you could
test them now. The Zener diode is faulty, if it shows either no or full-scale deflection when operated reverse-
biased as well as forward-biased.
If you cannot find a proper Zener diode, you could get around with the following: Get a green LED and place
this pseudo Zener diode into the meter in
forward-bias
. The threshold voltage will be displayed.
The circuit diagram for this experiment is shown in Chap. 3, Fig. 3.46.
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...
