Related Manuals for PV Electronics SN-18
Summary of Contents for PV Electronics SN-18
- Page 1 Assembly Instructions User Guide Nixie Clock Type ‘SN-18’ Software version: V1.0 PCB Revision: 13 July 10 Nixie Clock ‘SN18’ - 1 - www.pvelectronics.co.uk...
- Page 2 1. INTRODUCTION About the clock Nixie clock type ‘SN18’ is a Single Digit Nixie Tube Clock. It can be used with two types of tube: IN-18 with a digit height of 40mm or type IN-8 with a digit height of 18mm. These tubes originated in the USSR.
- Page 3 Safety DANGER: The clock pcb includes a switched-mode voltage booster circuit. This generates nominally 170 Volts DC, but is capable of generating up to 300 Volts before adjustment. Assembly may only be undertaken by individuals who are suitably qualified and experienced in electronics assembly, and are familiar with safe procedures for working with high voltages.
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Page 4: Tools And Equipment Required
2. TOOLS AND EQUIPMENT REQUIRED Tools required to assemble the PCB The following tools will be required to assemble the PCB: - Soldering iron with a small tip (1-2 mm) - Wire cutters (tip: A small pair of nail clippers works very well for this function) - Wire strippers (tip: A small pair of scissors is quite suitable) - Multimeter... -
Page 5: List Of Components
3. LIST OF COMPONENTS Table of components Circuit Designation Part Description Resistors 100R, ¼ Watt 5.6K, ¼ Watt 390K, ¼ Watt 3.9K, ¼ Watt 10K or 5.6K, ¼ Watt R6, R7, R8 100R, ¼ Watt R9, R10 1K, ¼ Watt 100R, ¼... - Page 6 Parts list / Packing sheet Part Description Quantity Resistors 100R, ¼ Watt 5.6K, ¼ Watt 1K, ¼ Watt 390K, ¼ Watt 10K, ¼ Watt 3.9K, ¼ Watt Capacitors 470uF, 16-25V, Electrolytic 100uF, 16-25V, Electrolytic 1uF, 250V, Electrolytic 22pF, Ceramic 0.1F Supercap 100nF Ceramic Transistors IRF730 N-Channel Mosfet...
- Page 7 How to identify the correct components Resistors: The resistors are easy to identify by the coloured bands across the cylindrical body. Using a multimeter it should will be possible very quickly to identify the different values. Transistors: The MOSFET Q2 can easily be identified as it has a large metal heatsink.
- Page 8 ASSEMBLY OF THE PCB Diodes D1 and D2 Start by bending the leads of these two diodes to approximately match the spacing of the holes on the PCB. Insert the diodes taking care to match up the white bands on the components with the component marking on the PCB.
- Page 9 Resistors: R1 – R11 R5 sets the current through the Nixie Tube. Two values are provided, catering for an IN-18 tube (5.6K) or an IN-8 tube (10K). Choose the value for the type of tube your will be using. All the resistors are installed vertically to save board space.
- Page 10 C1 and C2 Place C1 and C2, the small ceramic capacitors. They may be a different colour to the ones shown below. Trim the leads short and clean on the base of the PCB. Figure 8: C1 and C2 Q2 and IC1 These components look identical except for the part marking so be very careful in placing these two components: Q2: MPSA42...
- Page 11 C6 and WWVB / DCF connector C6 is a high capacity ‘Super Capacitor’, intended to keep the processor powered in the event of a main power failure. It is vital that it is placed in the correct orientation. See figure 10 below. There are arrows on the component that need to be pointing the same way as the arrows on the PCB.
- Page 12 VR1 and Q1 Place these components as shown below. You can bend Q1 over slightly to make it lower profile depending on your case plans. Figure 12: MOSFET Q1 and VR1 Inductor L1 Place L1 in position, and ensure it is as close to the board as possible.
- Page 13 4.10 C3, C4 and C5 Now it is time to solder in these three electrolytic capacitors. These components must be placed the correct way round or else the circuit will fail. Each capacitor has a positive lead, which is the longer lead, and a negative lead, marked by a white or grey stripe on the body.
- Page 14 4.11 X1 – Timekeeping Crystal X1 may now be placed as show below. It does not matter which way this component is placed. Be careful not to overheat this sensitive component. Figure 16: Crystal X1 4.12 Socket Receptacles for Nixie Tube The next step is to place the 14 or 11 sockets for the Nixie Tube.
- Page 15 Figure 18: 11 Socket receptacles placed for mounting the IN-8 tube 4.13 PM LED (D7/PM on schematic, ‘PM’ on PCB) This LED is optional, and if you will only be using the clock in 24 hour mode, is not really necessary. When lit, it indicates ‘PM’. Please note that it indicates PM for the time of the clock only, not AM/PM during alarm set and time set modes.
- Page 16 4.14 Seconds LED (D5/SECS on schematic, ‘SECS’ on PCB) This is a bicolour (red or green) LED. It flashes each second: red if the clock has no valid WWVB or DCF lock in the last 24 hours, or green if the clock had a WWVB or DCF lock in the last 24 hours. It flashes red/green whilst actually receiving a WWVB or DCF frame.
- Page 17 4.15 Display LED D6 A blue, or white (optional) high intensity is installed on the SOLDER side of the PCB to shine under the tube and give a pleasant glow. It can be switched off under software control, or if you will never require its function it may be omitted.
- Page 18 4.16 Decoupling capacitor C7 This is recommened for stable operation of the PIC16F microcontroller. Solder it directly across the middle two pins of the IC socket on the SOLDER side of the PCB. Ensure it points away from the white markings of where the Piezo sounder will be placed. Figure 24: Decoupling capacitor C7 4.17 Piezo sounder LS1...
- Page 19 4.18 Push buttons SW1, SW2, SW3 These are mounted as shown below on the SOLDER side of the PCB, however if you wish they may be placed on the top, COMPONENT side. Figure 26: Push button switches on the SOLDER side of the PCB Nixie Clock ‘SN18’...
- Page 20 4.19 Making up the power input lead Start by identifying the three connections on the socket as shown in figure 27, and follow these instructions: Figure 27: Identify and snip off Figure 28: Bend the remaining leads the unwanted lead as shown.
- Page 21 ASSEMBLING THE WWVB OR DCF RECEIVER MODULE This section is only relevant if you have purchased the optional WWVB or DCF receiver module. Assembling the Module First, insert the 4-way right angle header pin strip as shown below, and then attach the antenna by soldering the wires to the ‘ANT pads on the PCB.
- Page 22 TESTING OF CLOCK If you have reached this point and followed the correct order, then all the components should now be on the board except the PIC16F controller.It is recommended that at this point the power supplies are tested before installing the Nixie tube. To do so, you will need to have the 9-12V power adapter to hand.
- Page 23 Testing and setting up the clock After testing the power supplies, unplug the power supply. Taking care not to bend the tube sockets, gently insert the Nixie tube into its sockets. Do not insert the WWVB or DCF module yet, that is best done after you have familiarised yourself with the clock and set the non-volatile configuration settings for your location and preferences.
- Page 24 Whilst snoozing, you can press and hold ‘ALARM’ to cancel snooze. Alarm will remain set for the same time the next day, unless cancelled by making the On/Off setting to 0. Accessing the configuration menu Disconnect the power to the clock. Hold and press ‘SET’ button and then power up.
- Page 25 Parameter Description Values 12 / 24 Hr mode 0 – 12 Hr 1 – 24 Hr (default) Radio Time Rx Hour 0-23 (default 2) Radio Time Rx period 0-50 (default 10) (mins) Radio Time Signal Source 0 – No Radio Time Source 1 –...
- Page 26 CALIBRATING THE CRYSTAL TIMEBASE If you will be using WWVB or DCF sync, and you are prepared for the clock to be some seconds out of time each day, then this sections is not relevant. To calibrate the crystal timebase, first disable WWVB or DCF Sync by setting parameter (4) to 0.
- Page 27 INSTALLING AND USING THE WWVB OR DCF RECEIVER Ensure you have enabled DCF or WWVB reception and set the appropriate time offset value, plus WWVB DST disable bit if needed (probably only needed if you are in Arizona). Disconnect main power to the clock.
- Page 28 To exit WWVB or DCF reception, press the ‘SET’ Button briefly. To comand a WWVB or DCF sync manually from time display modes 1,2 or 3: Press ‘ADJ’ until a short bleep is heard. Nixie Clock ‘SN18’ - 28 - www.pvelectronics.co.uk...
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Page 29: Circuit Diagram
8. CIRCUIT DIAGRAM Nixie Clock ‘SN18’ - 29 - www.pvelectronics.co.uk...