Figure 4B.2. This is an oscilloscope photo very similar to Figure 4B.1. The top curve rises to 9 mA at 20 volts. At this point it is curving from being almost vertical to almost horizontal. It passes through 10 mA at 25 volts, 10.75 mA at 100 volts and ends at 11 mA at 180 volts. The second curve rises to 6.5 mA at 20 volts where it is curving over to being horizontal. It passes through 7.6 mA at 40 volts, 7.8 mA at 100 volts and ends at 8 mA at 180 volts. As above there are 5 more curves. The lowest one has a maximum current of 0.8 mA. End verbal description.