Blub clock


The Blub is a single-tube nixie clock – all digits of the time are rotated on a single digit display. It sounds complicated, but it works surprisingly well. The time is kept internally by high accuracy real-time-clock chip.

Blub Nixie Clock

The Blub is a single-tube nixie clock – all digits of the time are rotated one by one on a single nixie tube. It sounds complicated, but it works surprisingly well. The time is kept internally by high accuracy real-time-clock chip.

TODO: Gif animation

Manufacture of nixie tubes and nixie clocks in low quantity is an expensive task. With the Blub, I want to arrange the fabrication so we can make the clock as affordable as possible, without cutting corners. Thanks to the work we put into the preparation of the production, we can spend less time with the actual building of the electronics and troubleshooting and focus more on the development of the nixie tubes in production – and this is the main goal of our little business.

As affordable as possible without compromising on the function.

To optimize the price tag while keeping the quality, we need to manufacture this clock in higher quantity. Higher quantity allows us to spread the fixed costs to more customers. One design flaw in the big amount of clocks would mean a serious problem as the replacement costs would be high. So the whole electronics design of the Blub clock was developed with the aspect of function, longevity, and reliability kept in mind.



Heart of the clock is made of Atmega328p microprocessor paired with DS3231 high accuracy real-time clock for time-keeping (DS3231). This setup makes the clock fully standalone unit without the need for external time synchronization. The user interface is created by two push buttons on the back of the clock. Besides the buttons, the Blub clock contains a mini USB connector that is used as a connection to a power supply and offers advanced configuration options over a serial line.

Physical appearance

The clock case is milled of a solid aluminum block, sandblasted with fine glass beads, and finally anodized. The same material finish we use for our Zen and Puri clocks. It looks amazing, it is resistant to scratches and also the dust is less apparent on it.

Blub case
Blub case


For the Blub clock, we’ve stepped up the final quality inspection procedure – we developed a semi-automated testing fixture. The development of this new tool was probably more complicated than the development of the clock itself – but in the long term, it will pay off in reliability of the electronics passing the test procedure. It allows us to test all necessary electrical parameters as well as software functions and features. All this helps us to achieve higher consistency in the quality of the product we deliver to our customers.

Blub test fixture
Blub test fixture


Having a batch of functional and tested clocks for sale is one part of the story – getting them to customers is a whole other thing. Our packaging uses a metal can designed for a paint (durable and low-cost thanks to mass production) with custom made foam inserts. Reliable, good looking, inexpensive. Just use a screwdriver to open it!

Blub packaging detail
Blub packaging detail


Single tube nixie clocks are special in one aspect – the character of nixie tube operation is very close to the optimal operation – individual digits are cycled regularly. There are no situations when the nixie tube would be showing only one digit for prolonged periods of time (e.g. like the first tube in a 6-digit clock). This feature allows the nixie tube to avoid cathode poisoning and achieve maximal theoretical lifespan – which should be, according to our calculations, more than 15-20 years.

Technical specification


Power consumption
1.25W maximum
Power connector
Mini USB
Weight of the clock
Full package weight
Height of the clock
Diameter of the base


Our goal is to make products that last. Therefore we provide 10 years warranty for our clocks and nixie tubes.
Learn more about warranty