159
Circuit 134:
NOR gate with moving-coil instrument
Setup information
Install the two transistors, the two diodes and the two resistors as shown in
Fig. 2.134.
The four jumper
wires come next followed by the jumpers, which serve as switches (shown dashed). For your guidance we
have labelled the switches with
high E1
and
high E2.
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 transis-
tors, 2 x 1N4148 silicon
diodes, 1 x 4.7 k
Ω
resis-
tor, 1 x 10 k
Ω
resistor,
1 x moving-coil instru-
ment, 1 x breadboard,
1 x 9V battery with clip
connector
Fig. 2.134:
NOR gate with
moving-coil instrument
Experiment
Even if everything is wired correctly, nothing will happen at first. Both “switches” are open, the needle of
the moving-coil meter is not moving. 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
Moving-coil instrument
low
low
high
no motion
high
low
low
full-scale
low
high
low
full-scale
high
high
low
full-scale
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...
