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So you want to build Axiris's IV-3 shield for Arduino , sourcing the IV-3 VFD tubes yourself, from any of the numerous ebay sellers, as I did. Firstly, it is important to note that, although the assembly manual for IV-3 shield refers to it as "IV-3/IV-3a/IV-6 VFD shield for Arduino", which would make you think one could install either IV-3, IV-3A or IV-6 tubes, this is not quite the case. The reason is the difference in pin configuration: IV-3: 9-segment + dot, 14 pins (1 not connected) (pin configuration is bottom view ) IV-3A and IV-6: 7 segment + dot, 12 pins (1 not connected) (pin configuration is bottom view ) and then, there is IV-3 v-82 , which I bought on ebay: 7 segment + dot, 14 pins (3 not connected) (pin configuration is top view ) IV-3 v-82 (as I named it, based on the printing on the back of the tube), is an amalgamation between IV-3 and IV-3A: - can be found in either 7 segment or 9 segment (+ dot), although only 7 segments are connected; - has 14 pins (a...

You are reading the first ever "review" of the Akafugu Nixie Modular Clock , a product yet to be released at the time of writing. Per, of Akafugu, generously offered to sell me the PCBs for this Nixie clock; the parts were sourced by myself. The Nixie Modular Clock shares a big chunk of the schematic with its older sibling, the Akafugu Nixie Clock . The goal of this latest design is, I assume from the name, the "modularity". Similar to the VFD Modular Clock , "shields" for various types and numbers of Nixie tubes will probably be developed soon. The hardware This Nixie Modular Clock is an Arduino-based, open source project, designed around ATmega328 running on internal oscillator at 8MHz. Like the Akafugu Nixie mk3, the high voltage source (180-200V) uses the MC34063 DC-DC converter, and the driver for Nixies is HV5812 . There are 3 buttons: 2 in the back, for setting up the time and alarm time, and another long-stem, protruding through the top board, for...

I recently bought on ebay the PCB for  this open source VFD shield , designed and made by Axiris, a company in Belgium. I was attracted by the solid documentation provided on their site, which includes the schematics (even Eagle files), assembly instructions, demo software, files for laser-cutting the enclosure. I should also mention the professional photos, rivaling those of the top sites (e.g. adafruit, sparkfun). Assembly went smoothly, as expected. I also expected it to work on the first try, like the other two VFD devices I built previously, the Ice Tube Clock and the akafugu VFD clock . I guess I ran out of luck :) But, as my kid would say, "losing is learning". This became an opportunity for me to actually go one step further than just soldering the components mindlessly (because the instructions are too easy :) This is how I learned what fascinating little devices VFDs are. They function similar to cathode ray tubes (CRT), used in the previous generation of TVs: ...

A while ago I built a battery-powered single digit Numitron clock.  There was nothing challenging about it. Each segment of a Numitron takes less than 20mA, like a LED, and requires between 3.5V and 4.5V to light up. So the segments can be driven directly from the processor or other TTLs (shift registers etc). Since Numitrons behave so similar to (7-segments) LEDs, why not use one of my old LED matrix shields to multiplex 4 of them, I thought. And instead of the current limiting resistors, I would use Schottky diode s, to bring them even closer functionally to LEDs. I would even be able to use the same interrupt-based code for multiplexing. I started the practical experiment with just one Numitron. The 7 segments are driven by a 595 shift register and the common electrode gets grounded through a ULN2803 gate. The diodes insure the current flows in one direction only and they also guarantee a maximum voltage of 4.5V on each segment. In practice, multiplexing does not work...

This single-digit Nixie clock is built on a piece of prototype board, as a ProMini shield, similar to two previous miniature clocks, the single-digit numitron clock and the 7-segment bubble clock . The shield holds the Nixie board and the high-voltage power source (both from Taylor Electronics). It also has a couple of buttons to set up the time and 4 LEDs to indicate the digit's position. Like the single-digit numitron clock, time is displayed by showing each of the 4 digits (as in HH:MM). But for a "clearer picture", I added the above-mentioned 4 different color LEDs. One of its nice features is that it works on the rechargeable 3.7V LiPo battery. The clock does not have an on-board RTC (lack of space), relying instead on the time-measuring capabilities of ATmega328 directly. So this clock will keep time for as long as the battery is kept charged (through the USB power cable). The photo below shows my "collection" of (un-synchronized) micro clocks. (Missing i...

There is no "dumb" display easier to connect to an Arduino (or any microcontroller, for that matter) than a numitron tube, even compared with the 7-segment LED display. This is because: unlike LEDs, it does not need current-regulating resistors; unlike LEDs, the segments are not polarized; just connect any end of a segment to Vcc and the other to ground and it lights up; basically, every segment is the filament of a light bulb, like those used in flashlights in the old days; like light bulbs, they even get warm after a while (hence their inefficiency); voltage range is pretty wide, between 2V and 5V; The most popular numitron tube is IV-9, which can be purchased these days on ebay for $5. Size-wise, IV-9 fits perfectly on a Arduino ProMini board, and so it can be soldered directly into the bottom holes of that board. The clock I made displays the HHMM-formatted time as a sequence of 4 digits. Since there is no RTC on board, the processor keeps track of passing time. The rech...

With my limited (read "non-existent") crafting resources (e.g. space, tools), the easiest way to enclose my Arduinix clock was by recycling  my late Chumby 's shell. Things almost magically fit together, with minimal thinking and work. I was able to cram inside the box a hand-wired Wiseduino with an Arduinix-remix shield and a 4-tube board. The old Wiseduino would have come in handy if I had any left. I made one using the protoshield from Sparkfun, which also has a connector for the Bluetooth JY-MCU module. Beside the ATmega328, this pseudo-Wiseduino board includes a DS1307 with coin backup battery and a 7805 voltage regulator. The tube board is attached with screws to an empty board that plugs in the Arduinix-remixed shield. (Note that one reason for "remixing" Arduinix was to re-arrange the parts sticking out, namely the mosfet and the capacitors, so that it allows another shield to be stacked on top.) The clock has no user button (I glued the original sno...

Many months ago I bought, attracted by the clearance price, the PCB for the " Nixie Driver Board Rev A " from "Cogwheel circuit works" store. I was hoping that, with all documentation in place, I would be able to build it on my own, considering it's controlled by an ATmega328 and the software was available, though not the source code. First thing to note is that the board uses mostly SMDs. If anything went wrong (and there was a high chance, since the PCB was already described as a " mistake the board house made "), the board would become a coaster. The schematic includes some exotic components, like the HV513 Nixie driver , not offered by digikey. Others are the DS1302 RTC and the optional DS32KHZ oscillator for RTC, which I heard of for the first time. But thanks to the detailed BOM, gathering the components was relatively (some of them are already discontinued, for example) easy. High voltage for the Nixie tubes is generated by a hardware PWM und...

Honestly, one of the reasons behind my latest infatuation with Nixie tube clocks is trying to understand why so many people got so fascinated so quickly and so suddenly with them, although they are not cheap, and although they simply show the time with 4, sometimes 6, digits. In any case, I'm in the bandwagon now. I designed an Arduinix(TM) variant, based on my previous observations . One of the main differences is that the components sit low on the board, so that a "tube shield" can be plugged on top, similar to akafugu's VFD modular clock . The top "tube shield" can host (at least in theory) up to six IN-2 or four IN-17 (four IN-12 would not fit). For the "IN-2 tube shield", I downloaded and used the eagle library called "russian-nixies.lbr". Guess what? For the digits to be shown vertically, the IN-2 part needs to be rotated about 45 degrees clockwise. I did not know that until I got my IN-2 tubes. Essentially, the IN-2 tube shield I ...

For "unknown" reasons, these days things don't move as fast as they used to. I have a dozen or so unfinished projects on my desk, most of them waiting for parts to arrive. And usually and unfortunately, when I get the long awaited part, something else is missing... or not fitting,... or not working. Today I was finally able to finish the " Open Source Nixie Tube Shield ", for which I pledged $15 on kickstarter in return for the PCB. Without paying attention to the schematic (was it even published before the campaign ended?), I thought it was just another variation of the same Nixie theme, which it really was. I expected to have all parts on hand already, including the Nixie K155ID1 driver Russian IC. Surprise! Instead, the circuit uses CD4028 decoder plus HV transistors. And that's where the 4 week wait is coming from. I liked the compactness of the board even before I soldered the almost 100 components. But I was a bit disappointed when I realized the shi...

This was not an easy project to finish. Anything that could go wrong, it did, due to a rare combination of ambiguous hardware kit design (that's what started it all), and bad luck (software bugs in Arduino IDE 1.0 nevertheless). In the end, I learned a few things, which made me a better person :) :) :) Please don't take this as a rant, nor as a (negative) review. As usual, the main purpose of the post is to document the experience and eventually help others troubleshoot similar problems they may have with the Arduinix shield kit . The first issue I had was not getting the high voltage (180V) required by the Nixie tubes. For some reason, the provided schematic and assembly instructions are ambiguous on the exact value of the C3. This made me look at other HV power supplies, with the conclusions captured in this post . Anyone taking a closer look at the Arduinix HV schematic will notice at least 3 differences compared to others using the same 555-based design: - the very importan...

Updated June 2, 2017 - added VFD power supply with automatic dimming (#4 in the list below), contributed by Ken This is a superficial review of the few schematics I encountered while building Nixie clocks, VFD clocks and Geiger counters (no tube amplifier just yet). Although the schematics seemed basic at a glance, they usually ended up being a challenge (that is, they rarely worked right away) for me. That's another reason I am trying to cover them here, so I can use this post as consolidated reference any time I need it. Tubes require high voltage to work. Some ( Vacuum Fluorescent Display ) need 40V, others ( Nixie ) 180-200V, and some others ( Geiger ) even higher, 400-1000V. The high voltages are generated these days by switching-mode power supplies. Essentially, there is only a handful of popular solutions, and each DIY tube kit picks one of these, based on size, power requirements, cost. In principle, a switching mode power supply, also known as "boost converter",...

I just finished assembling the latest version of akafugu VFD clock , the " MK2 ". Per, from akafugu, generously sent me the board for testing/review. It comes will all SMD components pre-soldered, and the processor pre-programmed. The rest of the components, all through-hole, I sourced on my own. Here is a photo of the kit as I put it together (I forgot to include the through-hole resistors though). Assembling was straightforward thanks to the combination of good board design and easy-to-follow instructions. The result is shown in the photo below. MK2 has some improvements over version 1: - newer processor ( Atmega32U4 , as the one used in Leonardo ); - 5V power source (vs 9V previously); - direct sketch upload from Arduino IDE ( no hacking required ); - integrated support (on-board 24LC256 eeprom) for four-letter-word feature; - all SMD parts (quite a few actually) come pre-soldered; - directly compatible with the existing (version 1) VFD display shields; - better clearance ...