We love it when you come back for yet another clock or, like this time, for a continuation of a project.
In the last few weeks, we focused on the production of 100 pieces of alphabetical nixie tubes for the SIMULATED series. The conceptual artwork we first worked on in 2017 will now have its next version. The intention of the SIMULATED is a game with a phenomenon called typoglycemia - which is the ability of the human mind to understand words even in the cases when the first and last characters are not in the right place. We are going to “play” with more nixie tubes, this time in clocks for you.
It is as if the whip is licking our backs as the dispatch deadline is very tight due to the new problems with pumping the nixie tubes.
We are not giving up. We are working hard. We are getting closer to our goal with each step and we know that everything will be done on time.
The test stand is filling up and just a few more H-nixie tubes and it’s done!
Next month we are shipping to Japan.
This month, the LitePlacer (an automatic PCB assembler) brings a glimpse of a better tomorrow. There is some fine-tuning to be done, but first PCBs are already being assembled and later modifications will take a minimum amount of time. However, there are still a few steps ahead to go until we can really save as much time as we would like.
This month, we moved forward again with the H nixie tubes and we have started the animation of lighting up the numbers.
Playing with the instensity of the glow, the subtlety of fading and power of the glow.
We cannot wait to see this installed in the planned dimensions, glowing around.
Small things often bring the most joy. Piece by piece our whole team works to let you know how
much we care about you - our customers - and the things we create for you. We wish you all the best
in the new year 2023. We hope something small from our workshop, like the video below, may call
up just a little magic of your smile.
Best wishes for 2023 - Video
The H nixie tube light for artwork is slowly growing in front of our eyes. And we have become a part
of it! Serial production H is already producing fully functional lines.
A new milling machine for our special projects.
At times, finding someone who would help us with the production of tiny metal parts in small amounts is a tough nut to crack. That is why we have decided to find our own machine that would put this problem out of the way. And here it is!
We've added a new seat to beautify our touch with you.
A place where the videos, photos, and texts we use to talk to you take shape.
We can't yet show it. But it's going to be huge. Different looks, different materials, different nixies... super exciting and super demanding project at the same time. We can't wait to reveal it.
The first days of H nixie tube in series production came. It was a long way with many problems, experiments, failures, and time spent in development before we arrived here.
The following steps will be about the development of tooling and procedures to get to reasonable costs of production.
Sometimes old things just need a little care to be perfectly functional again. We're really proud of this vertical lathe. It needed a few adjustments from our machinist Jiří, to clean it up, to replace the feed lever, and some other stuff.
The last problem in the development of the H tube was the oxidation of numbers (steel discoloration). Some of the methods to solve the problem looked magical. We used dry ice to create a smoke simulating gas flow in the glass. Now we know how to prevent oxidation. Now we can move on.
We can't imagine our work without a 3D printer. Over the last few months, we have created many fixtures to make manufacturing more efficient. Some of them even look nice, but the main reason behind these particular tools is safe handling of parts and tubes to prevent breakage and scratching.
Whenever we send clocks to our customers we can only imagine what they look like in their homes. But we enjoy seeing our clocks in different interiors and at different times of the day. Our new photos can bring you many different feelings through their atmosphere. Take a look and enjoy them with us.
Eva has moved from the production of the nixie tubes into the lab, where we can fully use her potential and push our limits. Let's open the gates of science to new possibilities in our projects.
Our team got a bit bigger again. Gabriela will make the nixie tubes, will take care of the storage room, and prepare your orders for shipment. We hope that your orders will arrive to you faster and of the highest quality.
We got a new tool for our lab - a laser engraver/cutter. It will help us to prototype metal sheet parts faster and more accurately. I can't wait to see it making those various small metal tabs for the H tube!
Finally, we have the first fully working H nixie tube. After all the frustrating problems. No internal shorts, no cracks in the glass. But that was easy, the difficult task is to bring it into production and make it reliable, consistent and profitable. There is so much handwork on that nixie tube!
Recently, everything became busier. We have more clocks to make (thanks to you!), there are more projects to develop, we work on the organization of our workshops and labs. This gave me the courage to hire a new colleague - a worker for manufacturing the nixie tubes. There were a lot of applications, we ended up hiring two people. Eva (a biophysicist by education - let's hope for a hidden talent) for that particular position and Jiří, a machinist. A lot of work with training ahead!
All the stuff from the previous workshop has been moved to the new room. White glossy floor, white walls, unforgiving space that forces us to really keep it tidy. And that's good when you occasionally need to bring in some vacuum equipment or tools from manufacturing.
It took us some time to scale the 4 digit Puri clock to 6 digit version, but I think we did it well. It is a little monster, more than half a meter long, and that's what we like on nixie clocks :-)
How good would it be to be able to see the composition of the gas inside the nixie tube? It would help us to understand better the physics behind the nixie tube and what influences its longevity. in January we've finally got the new lab into shape and can continue on building a system that will analyze the gas for us.
... 400 hours later, the 4 new rooms are ready for moving in. 3000 lux, I am getting snowblind every time I enter the workshop. But the camera loves it, with 100 ISO all the time.
The H tube is glowing! However, its manufacturing is a total nightmare and that is what we need to change. I am starting working on Iteration 1. The good point is that the electrical parameters are 100% as we expected. Cool.
In order to optimize the manufacturing processes, the ladies kicked my R&D mess from the manufacturing space. I am taking the last rooms at the castle, the plan is to turn them into a psychedelic white lab-workshop.
After months of putting together parts and tooling for the new H-tube, I attempted to make the first prototype. The chances to succeed were small and it was a fail, but I discovered millions of weak places for improvement. I believe I will see it glow soon!
The H-tube project served as an impulse to get into a project of a machine for the production of oxygen for our gas burners.
We are starting cooperation with Nick Stock - he will stock our clocks and tubes and send them locally to our US and CA customers. This way, we will deliver faster, without the hassle of the import process and at a slightly lower cost.
This is gonna be big, literally. A 5x5m wall installation, covered with 121 brand new nixie tubes - 150 mm in diameter. Now we only need to develop this tube :-) More on your Youtube channel (links on the blog).
Finally, I am making a decision to take a separate room for my office. In the 3rd floor. Suddenly I can spend more time in "deep work" without being constantly interrupted by the buzz in the production. And I have time to make videos for you on Youtube!
Sebastian worked for us for more than a year and he developed several projects that improved our nixie tube production - the new burn-in machine being one of them. Thank you!
An impossible thing happened, a big box with one important piece of old machinery arrived at our storage place. This piece will play a major role in the development of our new tube model! But first, we need to refurbish it :-)
After one year in development, Sebastian finally finished the new burn-in machine. There are still things to do (mainly fix some child diseases), but it is important that it is running and from now on we are collecting loads of data from the burn-in process of nixie tubes.
We are testing first prototype boards of new nixie clock - a Blub Clock. The Blub clock will be our most affordable nixie clock. But to get our price as low as possible, we have to be very efficient and polish quality/reliability of the electronics as well as ease of the assembly/testing process itself.
I've been working on a new tube project for quite some time - one of the most important parts is a stem (the glass/metal pins connection). The first results look so good!
We are catching up, Nixie Machine III was revealed, OOO clock was delivered to Grandhotel Pupp and we made significant progress on the new burn-in machine. And new very exciting project is in the pipeline! Read more in Blog.
I feel I need to reward us for solving the fog problem. Something what would make me smile every day. Still not right time for V8, so I am buying white paint for walls, white paint for floor and white racks for storing equipment. My kids totally love the result :-)
Okay, problem solved last day of April. We had to stop manufacture completely and fully focus on the problem. It is quite interesting and, as expected, pretty complex. I want to devote a separate article or video to it. It deserves it as it cost us over $20,000 in salaries, material (for rejects and tests) and analysis.
It seems we have a new problem in manufacture. Difficult one. Some of the tubes develops a foggy layer on internal side of the glass. Seems like a simple thing, but I can't find any correlation to our manufacturing processes and materials.
I started working on redesign of a Blub nixie clock, a single tube clock. This project was initially designed by Duncan Hellmers and introduced in a Kickstarter campaign, but never took off. I really liked the sleek and simple design, so we agreed on taking over the project.
Radim is prototyping new motion sensor for our clock - with this module it will be possible to turn on the clocks automatically only when there is someone around. This will prolong tube life and decrease power consumption (which is only 5-7W anyway). But first we need to get real field experience in testing!
We are intensively working on new burn-in/testing device for our nixie tubes. The main person in this project is Sebastian and he is pretty good at it. The progress is (as usual) much slower than I expected, but the result already exceeds my expectations. Two months and it should be ready.
I decided to revive our Youtube channel. I believe I managed to distribute the work among my coleagues effectively, so I hope to find time to documenting our successes and failures for our followers.
We attended the top Czech design event of the year - Designblok. My expectations were totally different from the reality. We spent much more cash than I expected and got much less orders than I expected :-) But we also established some cooperations there, so at the end of the day it might be worth the effort.
We've got a fresh reinforcement.. Sebastian, a fresh EE graduate joined our team. He already spent a month on an internship here last year, so the arrival is seamless and maximally efficient. Now the development of electronics will run at elevated pace!
We finished development of new clock - Puri Nixie Clock. A four tube clock with even more simplistic design. I picked the best from Zen clock and added some new features as polished bases, electronics hidden in the stand and some new safety features.
I met Radim, local student of electrical engineering. Together we make new cleaning system for parts for our nixie tubes. With Gravelli, we made a nixie clock with concrete stand.
June is practically only about preparations for Maker Faire in Prague - first Maker Faire in Czech Republic. I make several experimental projects - argon filled tube, red coating for our tubes, display with 22 tubes.
The castle is getting new windows - we need to prepare all rooms, cover all equipment with plastic foils and then tidy all from dust. We develop first version of packaging for Puri clock.
I finally finished development of the colon tubes (separator tubes), it took me two years from idea to working sample ready for production. There were many unexpected issues over the time and I often felt it was a mistake to start with it as the resources spent on its development were so high. After plugging the colon tube into the clock first time, I immediately knew it was good decision to make them - this little detail make the clock!
Important addition to our machinery - I acquired two machines for sealing vacuum tubes, my first commercially made machines designed for vacuum tube production! This will help us manufacture different tubes in future. At nixie tube #4000 another set of improvements was applied to our glass to metal seals, lowering the leak failure rate close to 0%.
I am making a simple machine for cutting getters from strip, this is first project with usage of several pneumatic cylinders. And I finally get my new Prusa i3 MK3 printer!
Most of the clock orders from 2017 were shipped, on 15th I am opening orders again - and receiving tens of orders instantly. We need to work on optimizing of manufacture.
Monika unfortunately decided to leave, she would train Lenka (new employee) for tube assembly in following two months. I also need a help in office - I am hiring my sister Renata, she would communicate with suppliers, customers and will take care about packing and shipping our products.
We started working on a mobile application for control of our clocks. The app should be easier to use than web interface, I am curious to see the results. January was also a record month in sales - $70.000. And exhausting, no further R&D was done - I can devote my time either to making of nixie clocks or doing development..
Money issues solved, payments are flowing again to our account. I am finishing mechanical design of the colon tubes. We are working on a new clock case made of concrete with Gravelli. I take the clock for EMC testing, passing!
Guys left home and all suddenly broke down. A problem with our payment gateway appeared and we would not receive payments from customers for six weeks. Our cash balance drop below $2,000. I just signed a contract for new website which will be our biggest investment so far. Key employee struggles with serious health issues, another key employee might leave because of health issues of a close relative.
Life can't be better.
Production runs perfectly, in addition we have beautiful autumn here. Daniil, a light bulb designer came to spend a month with us. Sebastian (student of electrical engineering) came for a month-long internship and seamlessly joined our development processes. We reached $30k monthly sales, our best month so far. Life can't be better.
Past months were pretty much frustrating and I swear the failures must never appear again. In following months I would reorganize half of the manufacture, standardize quality control and cleaning of all incoming parts and developing better leak checking procedures. Since tube #2500, the failure rate drops from 4% below 1%.
With the team waiting for me to figure this out, I was sourcing tungsten wire from all around the Earth and analyzing its cleanliness and surface quality. Eventually I found super high quality manufacturer in USA. Ten times higher price, quality wins.. It would pay off in following months.
Summer was mainly about improving reliability of our glass-to-metal seals. With current manufacturing techniques, we experienced 2.3% tubes to fail within 6 months from manufacture. Whole process of manufacture of glass to metal seals was revisioned, starting with material selection, quality control, leak checking etc.. The last batch of 400 tubes shows 0% failure rate so far.
I was reported of several multiple failures of our tubes, leakage. It was clear we have a problem in sealing again.. I stopped production and spent a whole week in lab. Contamination of the sealing wire was identified as a cause.
I am starting works on next model of clock - Puri Nixie Clock.
The Zen Nixie Clock manufacture is running at steady, but slow pace. We shipped over 100 clocks and received wonderful feedback from customers!
A very high end clock by Frank Buchwald was released by M.A.D. Gallery, its name is Nixie Machine II and it features our R|Z568M nixie tubes. The electronics was also developed in our lab, it has all the neat features you know from Zen clock.
In February, I joined a Value Manifesto project founded by Timo Niemeyer. This project is so different from our other projects, cant wait to see it alive!
End of 2016
We end the year with $125,000 in sales, $25,000 profit. I devoted almost all my time to development of nixie tubes, no other activites were done in 2016 - goal for that year accomplished.
New orders for Zen Nixie Clocks and our nixie tubes are still coming at steady pace. Its clear we will need more room and help. I am renting three new rooms at the castle, doubling the total area to 250 square meters (2700 square feet). The financial situation is getting better, so I risk and hire a skillful women (Katerina) to train her to glassblower’s tasks. We purchased a set for etching metal sheets to be able to do prototypes and development samples very fast. To speed up production, we got a fully automatic laboratory washer for washing tube parts prior to assembly instead of doing it manually.
We still don’t have anodized stands for our clocks, our supplier tried four batches with horrible results. I keep searching for good supplier.
I deliver nixie tubes for first two Bombe clocks by Paul Parry (Bad Dog Designs).
The video documentary covering the manufacture of nixie tube at our lab is finished and published on Youtube. In few weeks, with 500k+ views, it becomes the most popular vacuum tube related video published on Youtube. We get attention of customers beyond the group of nixie tube geeks which brings us new orders. The stands for first Zen clock batch are not yet ready, getting bad news from manufacturer. I am changing supplier of raw material and also machining supplier.
I am gettingt 10 orders for Zen clocks immediately, I am accepting more orders with uncertain delivery time. The production of tubes is running without issues, all other parts as well – except the aluminum stand. Our supplier is not able to achieve the same good results as in first prototyping batch. We need to order machining of new batch of stands, the shipping is delayed.
Small prototype run of Zen Nixie Clock is finished. We have manufacturing processes set up and suppliers for all parts we don’t produce ourselves. I opened pre-order possibility for the clock, limiting it to 10 pieces only to make sure the clocks will be manufactured ontime (in September) without delays.
I deliver over hundred tubes to Duncan Hellmers for Blub Keo single tube nixie clock.
We have first Zen Nixie Clock boards among customers, collecting feedback, improving the firmware. One of the demands is for a case which would protect the tubes and provide a decent-looking way how to showcase the Zen clock. So I am designing a minimalistic case with aluminum stand and glass cover.
We’ve just made R|Z568M with serial number #800, unbelievable! The most time consuming task for this month was to figure out software bugs in first revisions of the ZEN nixie clock.
I am working on making the production of R|Z568M nixie tube more and more efficient, focus is also on little details. It turns out that hiring Monika was great decision, she learns fast and does great job. I also finished some interesting projects – a set of nixie tubes for a Clive Maxfield and his wonderful steampunk style clock. Another finished project is a Sturnus clock which was made together with Daniil Kondratyev under Glowguardian studio.
First revision of the long-promised six tube clock board is out! I name it ZEN nixie clock, a calm and peaceful way of displaying time. One feature for all – it is connected to internet and all the settings (time zone, display effects) can be adjusted in real-time from user account on our website. Also the time is synced automatically from internet.
After months of hesitation, I hired first employee (Monika), finally! Now I am able to delegate some tasks and devote more my time to development.. I also finished new pumping and filling station for my nixie tubes, this will speed up the manufacture and also provide a bit more consistent results.
We almost run out of money, at last moment a japanese customer appears, ordering nixie 18 tubes. I can pay rent for next quarter. Subsequently I get few more orders.
The goal for 2015 accomplished (to not lose money). Sales of nixie tubes $15,643. Sales of selling refurbished vacuum equipment is around $37,000. We ended the year with small profit ($625). Goal for 2016 - get rid of other activities, focus on nixie tubes only.
End of 2015
I rented new room in the castle, made it a kind of clean room and moved entire process of tube manufacture into it. The process is now cleaner and well organized. I am spending a lot of time on building new pumping station which will achieve the same high vacuum levels as the old one, but will be much faster and easier to operate.
Our twins go to kindergarten, Eva (my wife) joins me and took on administrative work - invoices, accounting etc.. This is big help as I can spend my time on R&D and not get demotivated by piles of papers..
I am making 100+ tubes as a replacements for the bad ones, ouch!
Most frustrating part of the nixie project so far – my first customers reports failures of the early tubes (under S/N #200). This sends me back to lab and I spend months by testing individual materials, gas pressures, gas mixtures, gettering processes, cleaning process and many more. The cause is soon identified – improper curing procedure of ceramic adhesive inside the tube, uncured compound slowly outgas spoiling the gas inside the tube. The overal processing of the tube is re-engineered and since then on I go the way of ultimate over-enginnering of everything. Just to make sure I will not experience situation like this again.
I had been watching amazing work of Berlin based designer Frank Buchwald for quite some time – his industrial-monster-insect style is just unmistakable. When I see his Nixie Machine he made for M.A.D. gallery, I simply have to meet him!
Beginning of 2015: It has been 3 years of very intensive work on nixie tubes now, 10+ hours every day, weekends included.. A goal for this year is clear – to not lose money, cover all expenses from our sales.
End of 2014
Emails from people all around the world start coming, I am really happy that I have customers. I focus on simplifying of the manufacturing techniques to cut down the amount of time spent on a nixie tube so that I am able to offer reasonable price for customers. The price settles on USD $175 per tube which covers the manufacturing time, shop rental and also keep some profit for another investments into equipment. I am still running on household savings which are shrinking fast..
The one-tube nixie clock is developed, I name it Solitube clock - a solitary tube. I sell 20 pieces of the clocks mostly to friends who have been following my stubborn efforts for quite some time. I am receiving first feedback from customers, great! I also hired a part time coworker Karel, he helps me with vacuum stuff refurbishment and do some small tasks on the tubes. Karel is smiling all day long and would cheer up all the team in following years.
I think I am now ready to prepare first small batch of nixie tubes. I decide to design a one-tube nixie clock and find first customers who would help me to test the whole product – from the electronics to the nixie tube itself. The tubes that I make in this time differ slightly in shape, definitely not ready for a 6-tube nixie clock – the differences would be visible immediately. I take on another room in the castle, another 65 square meters added to workshop.
I hire accountant, the complexity of importing and exporting all over the world is now so high I need to hand over it to a pro. I move all my nixie tube activities under separate company.
Beginning of 2014
This period is mostly about refurbishing and selling of all the vacuum equipment. I am able to buy many pieces for myself for reasonable price, so every cent earned goes back again to tube-making equipment. I am getting familiar with turbo pumps, roughing pumps, controllers, vacuum gauges, vacuum valves and all the other stuff. I am also building a device for activation of getters inside the nixie tubes, called flasher. This is the last tool I need to complete the whole production procedure of a nixie tube.
End of 2013
The garden shed starts to be too small for my stuff and I am soon going to move all the equipment for refurbishment from the company to my workshop. I have to find new room to rent. The closest place for rent is a castle from 17th century in neighbour village. The rent there is the same or lower than other places around and is also closest to my current workshop.
I am moving the turbos and other equipment to my first room in the castle, my workshop area grows by 50 square meters to 85 total together with the garden shed.
Second half of 2013
Another crucial moment came to pass. I’ve just found an advertisement of vacuum oven for sale offered by local company.. I am calling there whether I can come and check it out. Jumping to car and heading to the company which deals with stuff bought in auctions from bancrupted companies. What I see there takes my breath away – pallets full of modern vacuum equipment, tens of turbomolecular pumps, controllers, high vacuum gauges, valves, system components etc.. Having no experience with such kind of equipment, I immediately come up with idea to refurbish, test and sell the equpiment. It was first time I actually met a turbomolecular pump, however I was brave (or mad) enough to offer the deal and we eventually agreed.
Beginning of 2013
I am working on improvements of current nixie tube. In the meantime, the ShanghaiTime clock is being exhibited in Shanghai Museum Of Glass together with other 19 glass art objects from Czech Republic. Visitors can vote for the most interesting project and the ShanghaiTime gets nice second prize!
I work only on nixie tubes and the nixie clock I designed for the contest, 10-12 hours per day in average, weekends included. I dont remember anything but the shop from this month! After really intensive development, I made it! ShanghaiTime nixie clock. The first nixie clock with newly handmade nixie tubes!
I made first prototype of real nixie tube, with proper inner structure and gas mixture. Only the glass bulb was a bit weird as I had to make it from small diameter tubing.. And I also discovered a glass-art contest organized by Czech glass manufacturer Preciosa. Okay, let’s consider myself a glass artist for a while ;-)
I got samples of the metal parts for the inner assembly, the quality was absolutely exceptional! And after almost half year of building of the garden shed, I finally finished it! I started moving the stuff from the attic, 35 square meters of a room just for my equipment!
One morning, I found eBay listing for a big industrial Heathway glass lathe on eBay. Great price (only £1.300), similar piece was offered on US eBay for $12.000 recently. I checked the pictures, the machine seemed to be in good shape. The only problem was that it was sitting in England, 2000km from my shop – 800kg heavy machine!.. I decided to take a risk and bought it immediately. It turned out that the lathe comes from a cancelled university glass shop and the man who sells it is glassblower who worked there. So I paid it and started organizing a transport. It was pretty difficult, but finally, after tons of emails and calls, I found a small company that made it! They brought the lathe and put down on a concrete block in my garden that I made two years ago just for the case I will need a big machine.. There was no garden shed by the time they put it down.
I started looking for a manufacturer of metal parts for the nixie tube inner assembly. I got samples from local company (local companies are first to ask to as I want to support local businesses), but it was not good enough. I found that most of the european companies don’t even reply to my emails, thats frustrating.. I also started rebuilding my torch system to oxygen concentrators as an oxygen supply instead of liquid bottled oxygen.
I finished the bakeout oven, it will help me to achieve higher vacuum in the tube. The helium detector broke down, old transformer stopped working - I am searching for someone who would manufacture that part from scratch..
I am working on new gas filling manifold, it should be able to supply neon and argon to nixie tubes. I also made a test tube for experimenting with gas discharge. And when I finally made a neon bottle connector, I was able to use a homemade vacuum needle valve to fill a test tube with neon and enjoy the real bright neon glow, much better than argon! Shortly, I made first sealed tube with neon – I mark it “lab sample No.1”.
Our new house is built and we are moving, I am leaving the shop in basement and building new one in attic of our new house. I now have more room, but I need to be careful with flames. I am building an oven for baking out the tubes.
It took months, but the helium leak detector is fully repaired and running! I also made another design for the glass lathe, v2.0.. I am spending lot of time with family (three babies now), but there is still time to make progress.. I set up a new glassworking torch with oxygen/gas manifold, some other torches, small glass saw, new spot welder (working perfectly), a chuck for the glass lathe and some other minor things.
I got a bunch of old vacuum tubes and started to study their inner structure, seals and other details. One night, after a celebration of newborn twins with friends, I sat at the computer and found eBay listing offering Alcatel ASM 51 helium leak detector, I was in very good mood so it didn’t last long and it was on the way to me! This machine was one of the most important addition to my shop!
A crucial thing happend – I was contacted by a Ron Soyland through my blog, skilled man who had been successfully making vacuum tubes at home for ten years by then. This was the most important benefit of my blog as Ron would willingly share many of all the knowledge I need for making my own tubes. We would more than 2.000 emails during 2012 and 2013!
I made first experiments with gas discharge (in air). It was pretty exciting, so I bought argon to see what the noble gas will do! The HV power supply was a must, so I build one! I also started making my own glass lathe, it never worked much well.
I need tubes bigger than tiny IN-14, however buying six pieces of Z566M or similar means spending of around $250. Quite a lot. (!) Looking on the simple glass tube and metal structure inside, I got the idea of making nixie tubes myself. I thought I would just find a book with detailed description of how nixie tubes had been made. However, it turned out I was too naive – information about nixie tube manufacture were pretty scarce! But I didn’t give up, after some time, I collected basic information and got idea of sharing them publicly. It was a difficult decision as it is natural to protect your know-how, but I eventually started to write a blog about my efforts to make nixie tubes at home.
I ordered my first nixie tubes from eBay, small russian tubes IN-14, this was actually my first physical encounter with vacuum tubes.
I discovered nixie tubes accidentally when browsing internet.