232
2.98 NAND and NOR gates
Circuit 207:
NOR gate with LED
Setup information
Install the two transistors, the three diodes and the four resistors as shown in
Fig. 2.207.
The eighteen
jumper wires come next followed by the jumpers, which serve as switches (shown dashed). For your guid-
ance, we have labelled the switches with high E1, low E1 and high
E2
,
low E2
. Check the placement on the
board again and only then connect the battery.
Components required:
2 x 2N3904 transis-
tors, 2 x 1N4148 silicon
diodes, 1 x red LED,
3 x 1 k
Ω
resistors,
1 x 10 k
Ω
resistor,
1 x breadboard, 1 x 9V
battery with clip con-
nector
Fig. 2.207:
NOR gate with
LED
Experiment
Even if everything is wired correctly, nothing will happen at first. Both “switches” are on
low
, the LED is
off. The potential at the output is
high
. The following table, also called truth table, shows what will happen
now at the different switch states.
Input 1
Input 2
Output
LED
low
low
high
dark
high
low
low
illuminated
low
high
low
illuminated
high
high
low
illuminated
Summary of Contents for ELECTRONICS EXPERIMENTS BOX
Page 4: ......
Page 265: ...267 Fig 3 56 Cir cuit 56 Audio limiter Fig 3 57 Circuit 57 Amplifier for a storm detector...
Page 269: ...271 Fig 3 64 Circuit 64 Stabilizer for 1 9 V Fig 3 65 Circuit 65 Stabilizer for 2 5 V...
Page 275: ...277 Fig 3 80 Circuit 80 Quiztimer 30 seconds Fig 3 81 Circuit 81 Handy diode tester...
Page 315: ...317 Fig 3 179 Circuit 179 HF generator 150 kHz Fig 3 180 Circuit 180 HF generator 420 kHz...
