1. Set up the electronics as shown in Fig. 2.1.
2. Set the 996 Timer & Counter Display at X1.
3. Place the beta source 204Tl from the source kit at a
distance of ~2 cm from the window of the Geiger tube.
4. Adust the timer of the 996 for a long period of time
(~30 minutes).
5. Increase the (positive) high voltage on the 556 until the
Voltages