42
2.6 Double turn signals
Circuit 17:
Awesome double turn signals
Setup information
Install the two transistors as shown in
Fig. 2.17.
Install the two light-emitting diodes. Now it is time for the
six resistors. Finally insert the eight jumpers. Check the placement on the board again and only then con-
nect the battery.
Components required:
2 x 2N3904 transistor,
1 x red LED, 1 x green LED,
2 x 1 k
Ω
resistors,
2 x 22 k
Ω
resistors,
2 x 100 k
Ω
resistors,
2 x 10 μF electrolytic capac-
itors, 1 x breadboard, 1 x 9V
battery with clip connector
Fig. 2.17:
Awesome double turn
signals
Experiment
If everything is wired correctly, the two LEDs will start flashing alternately. The flashing frequency is at 2 Hz.
Try out other values for the electrolytic capacitors C1 and C2 and the resistors R2 to R5. At times one LED
will glow longer than the other, usually the flashing frequency will be different; and at times the circuit will
not work at all. Then no LED will go on, or one will be steady lit or the other will not turn on at all.
The circuit diagram for this experiment is shown in Chap. 3, Fig. 3.17.
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...
