Pvelectronics Nixie QTC Plus Configuration guide

Nixie Tube Clock ‘Nixie QTC+’
2 (01 October 2018)
www.pvelectronics.co.uk
- 1 -
Assembly I structio s
A d
User Guide
Nixie Clock Type
‘Nixie QTC Plus’

Nixie Tube Clock ‘Nixie QTC+’
2 (01 October 2018)
www.pvelectronics.co.uk
- 2 -
REVISION HISTORY
Issue
Number
Date Reaso for Issue
2 01 October 2018 C5 changed to 15pF
Draft 1 29 August 2018 New document

Nixie Tube Clock ‘Nixie QTC+’
2 (01 October 2018)
www.pvelectronics.co.uk
- -
1. INTRODUCTION
1.1 Nixie QTC Plus - Features
 Hours, Minutes and Seconds display
 Drives a wide range of medium sized solder-in tubes
 Uses a Quartz Crystal Oscillator as the timebase
 12 or 24 hour modes
 Programmable leading zero blanking
 Date display in either DD.MM.YY or MM.DD.YY or YY.MM.DD format
 Programmable date display each minute
 Scrolling display of date or standard display
 Alarm, with programmable snooze period
 Optional GPS / WiFi / XTERNA synchronisation with status indicator LED
 Dedicated DST button to switch between DST and standard time
 Supercapacitor backup. Keeps time during short power outages
 Simple time setting using two buttons
 Configurable for leading zero blanking
 Double dot colon neon lamps
 11 colon neon modes including AM / PM indication (top / bottom or left /
right), railroad (slow or fast) etc.
 Seconds can be reset to zero to precisely the set time
 Programmable night mode - blanked or dimmed display to save tubes or
prevent sleep disturbance
 Rear Indicator LEDs dim at night to prevent sleep disturbance
 Weekday aware ‘Master Blank’ function to turn off tubes and LEDs on
weekends or during working hours
 Separate modes for colon neons during night mode
 Standard, fading, or crossfading with scrollback display modes
 ‘Slot Machine’ Cathode poisoning prevention routine
 Programmable RGB tube lighting – select your favourite colour palette
 729 colours possible. Have a different colour or your choosing every
hour, or autochanging colours
 Not AC frequency dependent – works in all countries
 All user preferences stored to non-volatile memory
 Additional wireless functions if XTERNA module used:
- Display of outdoor temperature in Celsius or Fahrenheit. Configurable.
- Min / Max temperature in last 24 hours
- Wireless, Auto Sync of time from GPS with auxilliary TCXO
- GPS Sync time, and time since last GPS Fix
- Voltage of XTERNA module battery

Nixie Tube Clock ‘Nixie QTC+’
2 (01 October 2018)
www.pvelectronics.co.uk
- 4 -
1.2 Tubes Supported
Each tube is soldered to a mini PCB 'Cell', making tubes easily
changeable. Through the use of 2 different cell PCB types, and
different configurations of the microcontroller, it is possible for the
kit to drive a wide range of solder-in tubes as detailed in the table
below. There are detailed and specific instructions for mounting
each type of tube, in sections 5.1 to 5.8 of this manual.
Tube types
Code
Co figuratio
Sectio
IN
-
14
A
5
.1
IN
-
8
-
2, ZM1177
A
5
.2
Z570
M, Z570
0M, Z57
M, Z57
0M,
Z574M, Z5740M, GN-9A,
B570M, TAF1 17A, TAU70 0,
F9080B, F9080BA, TAF109 A,
ZM1080, ZM1082, ZM11 4,
ZM11 5, ZM11 6, ZM11 6A,
ZM11 6L, ZM11 6R, ZM11 8A,
ZM11 8L, ZM11 8R
A
5
.
GNP
-
17A
A
5
.4
GNP
-
7A, GNP
-
7AH
A
5
.5
ZM1210, ZM1212
B
5
.6
IN
-
16
C
5
.7
CD66, ZM124
0
, ZM124
2
,
XN11,
XN12
A
5
.8

Nixie Tube Clock ‘Nixie QTC+’
2 (01 October 2018)
www.pvelectronics.co.uk
- 5 -
1.3 SAFETY
DANGER: The clock pcb includes a switched-mode voltage booster
circuit. This generates nominally 170 Volts DC. 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. If in doubt, refer to a suitably qualified engineer
before proceeding.
The voltages ge erated by this circuit ca give a pote tially
LETHAL ELECTRIC SHOCK.
DISCLAIMER: This product is supplied as a kit of parts, intended only for
suitably qualified electronic engineers, who are suitably qualified and
experienced in electronics assembly, and are familiar with safe
procedures for working with high voltages. The supplier, his agents or
associates accept no liability for any damage, injury or death arising from
the use of this kit of parts.
This is not a finished product, and the person assembling the kit is
responsible for ensuring that the finished product complies with any
applicable local regulations governing electrical equipment, eg. UL, CE,
VDE.

Nixie Tube Clock ‘Nixie QTC+’
2 (01 October 2018)
www.pvelectronics.co.uk
- 6 -
2. TOOLS AND EQUIPMENT REQUIRED
2.1 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 to trim the excess component leads after soldering.
(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 for voltage tests and for identifying the resistors.
- A small hot air gun will be needed to shrink the heat shrink tubing
over the neon lamp wires.
2.2 Materials you will eed.
Solder – lead / tin solder is highly recommended.
USE LEAD/ TIN SOLDER!
Lead free solder, as now required to be used in commercial products in
Europe, has a much higher melting point and can be very hard to work
with.
Desoldering wick (braid) can be useful if you accidentally create solder
bridges between adjacent solder joints.
2.3 Other items you will eed.
The clock kit does not include a power adapter.
The following type of adapter should be obtained and used with the kit:
Output 12V DC regulated, minimum power output capability of 500mA
Output plug: 2.1mm pin, centre po itive.
A suitable adapter is shown below:

Nixie Tube Clock ‘Nixie QTC+’
2 (01 October 2018)
www.pvelectronics.co.uk
- 7 -
3. LIST OF COMPONENTS
3.1 Table of Compo e ts – Driver Board
Circuit Desig atio Part Descriptio
Resistors
R1, R2 4.7 KΩ, ¼ Watt
R , R4 90 KΩ, ¼ Watt
R5 00 KΩ, ¼ Watt
R6 - R11 270 Ω, ¼ Watt
R12 4.7 KΩ, ¼ Watt
R1 – R15 1 KΩ, ¼ Watt
R16 – R21 4.7 KΩ, ¼ Watt
R22 – R25 15 KΩ, ¼ Watt
Capacitors
C1, C2 220uF Electrolytic
C 1uF, 250V,
C4 220uF, 16-25V, Electrolytic
C5 15pF Ceramic
C6 pF Ceramic
C7 100nF Ceramic
C8 0.1F or 0.22F
C9, C10 100nF Ceramic
Transistors
Q1 IRFD220 MOSFET
Q2 – Q4 EL817 Optocoupler
Q5 MPSA42
Q11 - Q14 MPSA42
Diodes
D1 – D 1N5819
D4 1N4148
D5 UF4004
D6 5mm Yellow LED
D7 5mm Green LED
D8 5mm Yellow LED
RGB1 – RGB6 APA106 RGB LED
Integrated Circuits
IC1 LM2576 5V voltage regulator
IC2 PIC16F19 8 8-bit microcontroller
IC HV5812
Miscellaneous
L1, L2 100uH inductor
AM1, AM2, PM1, PM2 4mm wire ended neon lamp
ALARM, SET, ADJ, DST Miniature push button
IC2 Socket 28 Way narrow IC socket for IC2
IC Socket PLCC28 IC socket for IC
Sockets for Q2 - Q4 12 Way SIL Socket Strip
J1 2.1mm PCB power socket
GPS / RFT Surface mount .5mm jack socket
LS1 Piezo sounder
FUSE 500mA fuse
Insulation 25 cm Clear insulation for neons

Nixie Tube Clock ‘Nixie QTC+’
2 (01 October 2018)
www.pvelectronics.co.uk
- 8 -
NX1 – NX6 2X6 way 0.1” header plug
X1 2.768KHz watch crystal

Nixie Tube Clock ‘Nixie QTC+’
2 (01 October 2018)
www.pvelectronics.co.uk
- 9 -
3.2 Parts list / Packi g Sheet - Compo e t Bag
Part Descriptio Qua tity
Resistors
270 Ω, ¼ Watt 6
1 KΩ, ¼ Watt
4.7 KΩ, ¼ Watt 9
15 KΩ, ¼ Watt 4
00 KΩ, ¼ Watt 1
90 KΩ, ¼ Watt 2
Capacitors
15pF, Ceramic 1
pF, Ceramic 1
100nF, Ceramic
1uF, 250V, Electrolytic 1
220uF, 16-25V, Electrolytic
0.1F or 0.22F 1
Transistors
IRFD220 MOSFET 1
MPSA42 5
EL817 Optocoupler
Diodes
1N5819
UF4004 fast recovery diode 1
1N4148 1
5mm Green LED 1
5mm Yellow LED 2
APA106 RGB LED 6
Integrated Circuits
LM2576 5V voltage regulator 1
PIC16F19 8 8-bit microcontroller 1
HV5812 1
Miscellaneous
100uH inductor 2
4mm wire ended neon lamp 4
Miniature push button 4
28 way narrow IC Socket for IC2 1
PLCC28 IC Socket for IC 1
12 Way SIL socket strip 1
2.1mm PCB power socket 1
Surface mount .5mm jack socket 1
Piezo sounder 1
500mA fuse 1
25cm Clear insulation for neons 1
2X6 way 0.1” header plug 6
2X6 way 0.1” header socket 6
2.768KHz watch crystal 1

Nixie Tube Clock ‘
Nixie QTC+’
2 (01 October 2018)
www.pvelectronics.co.uk
We recommend to check
are present before commencing assembly.
The resi
stors used in the kit are 1% tolerance metal film. They are
marked with 4 coloured bands to identify the value. However it is
sometimes unclear in which directio
Therefore, we recommend that the resistors be identified with a
multimeter.
Please note
the fuse w
confused for a capacitor. It is a self
T
he 10pF and pF capacitors will be marked 10 and
respectively. The 100nF capacitors will be marked 104.
Q1 (IRFD220) is in a very similar package to Q2
can tell the difference, in addition to the part marking by looking at
the pins.
Q1 has two pins that are actually joined at the resin body.
Q2 –
Q4 have 4 separate pins.
Inductors L1
and L2
Nixie QTC+’
We recommend to check
against the list above, to ensure all parts
are present before commencing assembly.
stors used in the kit are 1% tolerance metal film. They are
marked with 4 coloured bands to identify the value. However it is
sometimes unclear in which directio
n the bands should be read.
Therefore, we recommend that the resistors be identified with a
the fuse w
ill look like the picture below. It can easily be
confused for a capacitor. It is a self
-resetting fuse.
he 10pF and pF capacitors will be marked 10 and
respectively. The 100nF capacitors will be marked 104.
Q1 (IRFD220) is in a very similar package to Q2
–
Q4 (EL817). You
can tell the difference, in addition to the part marking by looking at
Q1 has two pins that are actually joined at the resin body.
Q4 have 4 separate pins.
and L2
may be one of three types:
- 10 -
against the list above, to ensure all parts
stors used in the kit are 1% tolerance metal film. They are
marked with 4 coloured bands to identify the value. However it is
n the bands should be read.
Therefore, we recommend that the resistors be identified with a
ill look like the picture below. It can easily be
he 10pF and pF capacitors will be marked 10 and
respectively. The 100nF capacitors will be marked 104.
Q4 (EL817). You
can tell the difference, in addition to the part marking by looking at
Q1 has two pins that are actually joined at the resin body.

Nixie Tube Clock ‘Nixie QTC+’
2 (01 October 2018)
www.pvelectronics.co.uk
- 11 -
4. ASSEMBLY OF THE PCB
DUE TO PRODUCT DEVELOPMENT AND IMPROVEMENTS,
YOUR PCB MAY NOT LOOK EXACTLY LIKE THE ONE
PICTURED.
4.1 Low Voltage Power compo e ts:
J1, FUSE
D1-D3 (1N5819)
D4 (1N4148)
IC1 (LM2576)
L2 (100uH I ductor)
C1, C2 (220uF)
Start by installing D1-D4. Align the band on the components with
the band marked on the PCB.

Nixie Tube Clock ‘Nixie QTC+’
2 (01 October 2018)
www.pvelectronics.co.uk
- 12 -
Bend the leads of IC1 as shown below then solder in place.
Continue to mount C1, C2, L2, J1 and FUSE. C1 and C2 are
polarized. The longer lead goes in the hole marked ‘+’.
4.2 Testi g Low Voltage Power Supply.
Identify the test GND, 5V and HV test points as shown below.

Nixie Tube Clock ‘Nixie QTC+’
2 (01 October 2018)
www.pvelectronics.co.uk
- 1 -
Plug in the power supply, and then test using a DC voltmeter:
Touch the black probe on the GND test point and the red probe on
the 5V test point. The voltage should measure between 5.6 and 5.9
Volts. If not, disconnect power and check your work. Do not
proceed with the assembly until the error is corrected. Once the
test is completed, disconnect the power.
4.3 High Voltage Ge erator compo e ts.
Socket for IC2
R1, R2 (4.7 KΩ)
R3, R4 (390 KΩ)
R5 (300 KΩ)
C3 (1uF)
C4 (220uF)
Q1 (IRFD220)
L1 (100uH I ductor)
D5 (UF4004)

Nixie Tube Clock ‘Nixie QTC+’
2 (01 October 2018)
www.pvelectronics.co.uk
- 14 -
Take care that the notched end of the IC socket is at the end
shown. However, if you find you soldered it with the wrong
orientation, do not try to remove it. It is perfectly fine with the
notch at the wrong end, just be sure to place the IC in the socket
with the IC’s notch in the correct position.
Also the MOSFET needs to be placed with the two joined pins at the
position shown below.
Ensure that the (-) light stripes on C and C4 are facing towards
each other as shown below.

Nixie Tube Clock ‘Nixie QTC+’
2 (01 October 2018)
www.pvelectronics.co.uk
- 15 -
4.4 High Voltage Ge erator Test.
- Refer to the warnings on page 5
- 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 HV test points,
measure the high voltage generated using a voltmeter on DC
setting. It should be between 164 and 176 Volts. If this is in order,
disconnect the power supply. If you do not get this voltage, do not
proceed. Refer to the troubleshooting section .
4.5 C5 (15pF)
C6 (33pF)
X1 (32.768KHz Crystal)
C7, C9, C10 (100 F but marked ‘104’)
(C7, C9 and C10 may be a different colour)

Nixie Tube Clock ‘Nixie QTC+’
2 (01 October 2018)
www.pvelectronics.co.uk
- 16 -
4.6 R13, R14, R15 (1 KΩ)
4.7 Q2, Q3, Q4 (EL817)
SIL Socket Strip
You will either receive 2 X 6 Way sockets, or a strip of 12 sockets.
If the latter, clip in the middle to get two 6 way socket strips.
Assemble the parts as shown below, paying attention to the
orientation of the dot on the body of the parts. Then solder the
sockets in place. Don’t solder the parts to the sockets!

Nixie Tube Clock ‘Nixie QTC+’
2 (01 October 2018)
www.pvelectronics.co.uk
- 17 -
4.8 R16, R17, R18, R19, R20, R21 (4.7 KΩ)
These are the anode resistors.
4.9 Socket for IC3
Align the notch on one corner of the socket with the marking on
the PCB. Be careful not to force in the socket if all pins are not
aligned. Ensure all pins are fully pushed through the holes before
soldering in place. If you find you soldered it in the wrong
orientation, don’t try to remove it. See the troubleshooting section.
4.10 NX1 – NX6 (6X2 way male pi header)

Nixie Tube Clock ‘
Nixie QTC+’
2 (01 October 2018)
www.pvelectronics.co.uk
Ensure the connectors are soldered very close to the PCB.
insert IC into its socket, with
to the front of the PCB.
Nixie QTC+’
Ensure the connectors are soldered very close to the PCB.
insert IC into its socket, with
the dot on the bevelled face pointing
to the front of the PCB.
- 18 -
Ensure the connectors are soldered very close to the PCB.
Also now
the dot on the bevelled face pointing

Nixie Tube Clock ‘Nixie QTC+’
2 (01 October 2018)
www.pvelectronics.co.uk
- 19 -
5. ASSEMBLING THE NIXIE TUBE CELLS
PLEASE REFER TO THE APPROPRIATE SECTION FOR YOUR NIXIE
TUBE TYPE.
5.1 IN-14 Nixie Tubes.
Code co figuratio : A (see page 36)
Cell PCB Type:
Start by identifying the anode lead at the back of the tube. It has a
white coating where it enters the glass. Then remove the wires
each side of the anode.
To facilitate easy insertion of the flying leads into the small holes, it
helps enormously to trim the flying leads with a pair of scissors as
shown below.
Start at the anode lead, then, working around the tube, cut each
sucessive lead approx 2mm shorter than the previous one. This will
allow you to feed each lead in in turn.

Nixie Tube Clock ‘
Nixie QTC+’
2 (01 October 2018)
www.pvelectronics.co.uk
Referring to the pictur
cell PCB.
Now you can insert and solder in the
tube sits squarely on the PCB
Keep the tube 5mm (0.2”) from the PCB.
this separatio will i validate a y tube warra ty claim.
The tube cell is now complete. Repeat for the other 5 tubes.
Then move on to step
Nixie QTC+’
Referring to the pictur
e below, identify the anode pad
Now you can insert and solder in the
tube. Pay
attention that th
tube sits squarely on the PCB
.
Then solder on the connector.
Keep the tube 5mm (0.2”) from the PCB.
Failure to keep
this separatio will i validate a y tube warra ty claim.
The tube cell is now complete. Repeat for the other 5 tubes.
Then move on to step
6.
- 20 -
e below, identify the anode pad
on the tube
attention that th
e
Then solder on the connector.
Failure to keep
this separatio will i validate a y tube warra ty claim.
The tube cell is now complete. Repeat for the other 5 tubes.