•
Set the control unit to ramp mode and con-
figure a minimum voltage of about 10 V, with
a maximum voltage of about 35 V.
•
Select a heater voltage of some 3.5 V and a
collector voltage of around -1.5 V.
Oscilloscope settings:
Channel 1: 50 mV/div
Channel 2: 0.2 V/div
BETRIEBSGERÄT FRANCK-HERTZ/OPERATING UNIT FRANCK-HERTZ
Heizung
Filament
F
K
Fig. 6 Connection of 3B NETlog
BETRIEBSGERÄT FRANCK-HERTZ/OPERATING UNIT FRANCK-HERTZ
Heizung
Filament
U
F
V
F
K
Fig. 7 Connection of oscilloscope to the control unit for the Franck-Hertz experiment
Gitter/Grid
Beschleunigung/Acceleration
0
12
0
80
U
U
U
F
G
Amin
Man/Ramp
V
V
V
G
TM
to the control unit for the Franck-Hertz experiment
Gitter/Grid
Beschleunigung/Acceleration
0
12
0
80
U
U
G
Amin
Man/Ramp
V
V
G
A
Time-base: 5 ms
Trigger on Channel 1
•
Vary the heating voltage, the upper and lower
limits of the accelerating voltage and the os-
cilloscope parameters until the best curve can
be seen.
•
In order to display the ionisation curve, re-
verse the polarity of the collector voltage.
Reverse bias
0
80
0
12
U
U
Amax
E
+/-
V
V
E
V
1
10
1
A
=
+
= *
U
U
U
I V
10
x
A
Y
E
Reverse bias
0
80
0
12
U
U
Amax
E
+/-
V
V
E
V
1
10
1
=
+
= *
U
U
U
I V
10
x
A
Y
E
6
Channel
On/Off
Rate
Date/Time
Store
in
+
I
A
out
out
U
U
A
B
in
in
+
+
U
U
A
B
OSCILLOSCOPE
CH1
CH2
EXT
(X)
(Y)