Nixie Tube Clock ‘Frank 3’
Issue 5 (1 Jan 2012)
www.pvelectronics.co.uk
- 14 -
4.5 High Voltage Generator Test.
- Refer to the warnings on page 4
- Insert IC2 into its socket. Orient the notch on the IC with the
notch on the IC socket and the PCB marking.
- Power up the PCB, and using the GND and 170V test points,
measure the high voltage generated using a multimeter or
voltmeter on DC setting.. It should be initially between 150 and
190V. Using the VR1 brass screw, slowly adjust the screw until the
voltage is between 170 and 175V. Disconnect the power supply.
- Finally, remove IC2 from its socket and replace on its static-
protective foam. It is best kept safe until needed for the tube tests
later in the assembly.
4.6 C4, C5, X1.
These are the timekeeping components: 32.768KHz crystal and
two load capacitors. See below:
4.7 D6 - D8, C6.
C6 is a high capacity ‘Super Capacitor’, intended to keep the
processor powered for short periods in the event of a main power
failure. It is vital that it is placed in the correct orientation. See
below. There are arrows on the component that need to be
pointing the same way as the arrows on the PCB.