Desk Clock with a VFD Display and Wi-Fi

In my reviews, I’ve often written that I like various VFDs—or rather, devices that use them. I’ve already reviewed a volume control, a signal level indicator, and even a clock. But while looking for something interesting on Taobao, I came across a store with a couple more interesting clock models. The price was reasonable, so I couldn’t resist.
Today I’m reviewing the first clock.


In fact, it was a lot more complicated than simply seeing them and buying them. The clock’s features raised a few questions, so I got in touch with the seller. One thing led to another, and I found out that he wasn’t just a seller—he actually designs and manufactures the clocks himself. What’s more, he agreed to make a few changes to his standard models to make them more convenient to use.

The link offers three versions of the clock: without WiFi, with WiFi, and the so-called "international version". Here’s a quick explanation of how they differ.
Without WiFi: a basic clock, but with a VFD.
With WiFi: the same clock, but with automatic and manual time synchronization with an NTP server.
International version: the same as the previous versions, but with time zones and daylight saving time.

Originally, there were only the first two versions. The third came about after I talked with the developer and he made some changes to the software, so that’s the one I’ll be writing about.

I ordered two clock models and a few light filters, so I received a fairly large package, with the clocks and filters wrapped up in layers of protective packaging.


For convenience, I’ve divided the clocks I ordered into "large" and "small" models. They differ both in case size and in the size of the display itself. I’ll start with the "small" one.

Since everything arrived together, I sorted out the contents of the package logically. The first clock comes with:
1. The clock itself
2. Power cable
3. Hex key
4. Two light filters
5. Rubber feet.


Since the product is sold on Taobao and is usually ordered through an agent, it can be useful to know the weight.
The clock itself weighs about 208 g, and the whole package is almost 270 g.
If you can pay directly on Taobao with a bank card, though, the seller can ship the package himself, without an agent. I asked him about eBay and AliExpress; he doesn’t plan to list it there yet, but might do so in the future.


The power cable has a USB connector at one end and a 5.5/2.1 plug at the other. The cable is very flexible, which is a plus.
There were also four self-adhesive feet and a hex key—nothing unusual.


There were also two light filters. The clock’s display color can be changed if you like. It came with the yellow filter installed, but you can swap it for a green or blue one. The hex key is included to make the swap easier. I’m not 100% sure the key will always be included, but I don’t think it’s essential: you can replace the filter without it, since the screw heads have a bit of knurling.
I was going to take my own comparison photo, but the seller’s photo shows the difference better. Personally, I prefer the yellow filter.

By the way, the filters have protective film on both sides, in addition to the paper backing, so you’ll have to take the clock apart either way.


And, of course, the clock itself. The case is made from aluminum extrusion. Given the type of display, I’d call it medium-sized rather than large.


The photo doesn’t do it justice, but I think the clock looks very neat. There are no uneven edges; everything fits together well. That said, with all the small CNC machines around these days, making something like this isn’t difficult.


There are two case colors, but it’s best to check with the seller about the color. I received a silver case, while the link points to a blue one. The international software version isn’t available for the silver model yet, but I expect that to be fixed.


There are three control buttons on the back: SET (mode selection), up, and down, which increase or decrease the selected setting.
To the right are the temperature and humidity sensor, a light sensor, and then the 5.5 mm power jack. Further to the right, there’s a hidden microUSB port that can also be used to power the clock.
At this point, I have two comments, which I’ll pass on to the developer:
1. Be careful with the 5.5 mm connector, since 12 V power supplies use the same type of plug.
2. The microUSB connector is recessed deep into the case, and the opening isn’t very large, so not every plug will fit.


On first power-up, the clock defaults to 0 hours and 40 minutes. I’ll explain why later.
If the date hasn’t been set, the display shows the temperature and, at first glance, the rather puzzling word “Day.”


As I mentioned, the clock has to be taken apart anyway, so grab the little wrench and remove the four screws on the back. There are eight screws in total, but you only need to remove the larger ones; the wrench fits only those.


The battery compartment is visible on the right. The battery isn’t included because of possible shipping restrictions. It uses a CR1220, but CR1216 and CR1225 batteries should also fit. You can get the cheapest one; in fact, you can leave it out altogether, since the settings are stored in nonvolatile memory.


The display is bright, but the camera flash washes it out without a light filter.


It uses a 16-character alphanumeric VFD, apparently built using CoG (Chip on Glass) technology, judging by the small number of pins. In other words, the display controller is built into the display, so there’s no need for a separate high-voltage driver; it’s controlled directly by the microcontroller (MCU).


Each character position is arranged as a 5x7 pixel matrix, so you can display almost anything. I’m thinking of asking the developer to show some of the information in Russian, with a proper translation, of course :)


The display has five filaments, and the illumination is very even. Unfortunately, the display manufacturer is unknown.


All the components are mounted on the back of the display board.


Unlike most common models, this one uses a proper temperature and humidity sensor. As far as I can tell, and judging by the fact that the seller also offers this board separately, it’s an HDC1080.
The stated accuracy is +/-2% for humidity and +/-0.2 degrees for temperature. There is one issue, though: although the sensor is set apart from the main board, it’s still affected by heat from the components and reads about 2-3 degrees too high.


I don’t have much to compare the humidity readings against, but I’ve seen it go as low as 11% at home. Since the radiators are still on, that seems entirely plausible. The sensor is responsive, so it reacts quickly to changes in humidity.


Overall build quality gets a solid four out of five, maybe even a four-plus. There are a few minor flaws, but in my opinion they’re not serious for a one-off build. The photoresistor for automatic brightness control is also mounted on the back, so the system may not work properly if you place the clock right up against a wall. That said, the power cable also plugs in at the back, so placing it flush against the wall would be difficult anyway.


1. Microcontroller that controls the clock.
2. WiFi module
3, 4. Although the clock synchronizes its time via NTP, it still has a separate RTC (real-time clock) module installed: RX-8025T made by Epson Toyocom.
5. A closer look at the temperature and humidity sensor
6. Unfortunately, it looks like the filaments are powered by DC, since there’s only one converter on the board, and it’s an LT177. I’ll have to ask the developer why they didn’t use a dedicated converter chip with filament-voltage and high-voltage generators.


The clock draws between 150mA at minimum brightness and 250mA at maximum brightness.


If there’s no battery installed, the clock starts counting from 0 hours and 40 minutes when powered on, but it doesn’t show the day of the week. The result is what you see in the photo on the right.
Once the time has synchronized or the date has been set manually, everything displays correctly. But as it turns out, even without a battery, the time and date don’t reset for about half a minute after the clock is switched off. The clock does stop while it’s powered down, though.


Now for the settings. As I mentioned above, there are three buttons on the back: +/-, and SET. With a single press of SET, the clock enters Wi-Fi synchronization and settings mode.
If the connection hasn't been configured, the time won't synchronize. If it has, press SET and the clock will synchronize in 30–60 seconds. Automatic synchronization also works; according to the developer, it happens at 2:22:22, although it seemed to me that it happens a little earlier. Anyway, it doesn't matter.

A separate note about the battery. Since the clock can synchronize automatically, the battery isn't really all that necessary. But I asked the developer to add an option to make the clock synchronize automatically when power is applied, instead of waiting until night or for a button press. The developer said they could add this feature.


The next 6 presses of SET cycle through the time (hours, minutes, seconds) and date (year, month, day) settings. The + and - buttons increase and decrease the value, respectively.


These settings are more interesting.
1, 2. The eighth press of SET selects the screen brightness adjustment mode: manual or automatic.
3, 4. The ninth press sets the brightness in manual mode, with 5 levels to choose from.
5, 6. The tenth press selects the font style: wide or "thin".
7. The eleventh press enables or disables automatic synchronization with an NTP server.
8. The twelfth press sets the time zone; the clock is set to Ukraine's time zone.
9. The thirteenth press enables or disables the switch between daylight saving and standard time.

The last two options were added to the "international" version of the clock. In China, not only do they not switch between daylight saving and standard time, but it turns out that even though China spans almost five time zones, they use just one time zone—Beijing time. So there's no need for time zone or daylight saving settings there.
To be fair, in provinces far from Beijing they do use Beijing time, but the start and end of the workday may be shifted to compensate for the time zone difference.


There are also four ways to display information on the screen.
First, the screens alternate: temperature + humidity + time / day of the week + time


In action


Second, just the time in the center, with hearts at the sides that blink in time with the seconds.


Third, almost the same as the second, but in day-of-the-week display mode, the date is shown instead of the time.




Fourth, almost the same as the third, but without the blinking hearts.


I've written about synchronization many times, and now I've finally got around to explaining how to enable it—or rather, how to connect the clock to a router.
First, you'll need the clock itself and something with Wi-Fi, such as a smartphone or tablet, and of course a router with an internet connection :)


To set it up, press SET once. The clock enters access point connection mode, but initially it acts as an access point itself so you can connect to it and configure it.
That is, if this is the first time you've turned it on, it will wait for a long time. If you've already configured it, it will first wait for a connection to the clock. If no one connects, it will try to connect to the configured access point itself and, if successful, synchronize the time and switch to normal display mode.


1. Enable connection mode, open your phone's settings, and look for an access point named WIF2GPS-xxx.
2. Select Connect and enter the password 88888888. For some reason, the password didn't work the first time for me, but I tried again and it worked fine.
3. That's it, the phone is connected to the clock.


Open a browser, enter 8.8.8.8 in the address bar, and go to that address.

1. Yes, the interface is in Chinese, but that doesn't really matter.
At the top, you can select an NTP server. I didn't change anything and left the Chinese one selected.
Below that are two fields for entering the access point name and password.
Further down, after the list of all available access points, there's a Refresh button. The module is very sensitive, so you'll also see a bunch of your neighbors' APs.
2. Find yours and enter its name in the top field. The name is case-sensitive.
Enter the password for your access point in the field below.
3. Click the button below, and when prompted, click OK.



A notification window then appears.

The instructions say that capitalization matters when entering the access point name. I tried it both with and without matching the case; the image that appeared afterward was the same, but as far as I remember, synchronization did not happen in the second case.
You can then close the browser or follow the link in the window, but you'll get a message saying there's no connection because the clock has reconnected to your access point.


After 10–15 seconds, the clock synchronizes, makes a short sound, and switches to normal operation with the time and date set.
The sensitivity was good enough for normal operation throughout the apartment. I'd estimate the setting accuracy at about +/-0.5 seconds.


An example of manually starting synchronization.





I've been using the clock for about a week now, and so far my impressions are entirely positive. Its accuracy is good enough even without automatic correction. I haven't measured it specifically, but I'd estimate the error at less than 0.5 seconds per day.
The time zone selection works, and I also checked the switch to daylight saving time just the other day. Everything worked fine.
I have no complaints about the appearance or the clarity of the characters either, but I already have a list of things I'd like to see in future versions, especially since the developer is open to suggestions:
1. An alarm clock—still undecided whether it's needed.
2. Automatic synchronization on startup, not just on a schedule or manually
3. Our date format: day/month/year instead of year/month/day
4. Possibly protection against 12 V being applied to the power input—still undecided.
5. A wider USB opening; not all plugs fit.
6. Scheduled brightness adjustment instead of using the sensor. I have a similar clock; it's convenient, but this is still undecided.
7. Days of the week in Russian; it's not yet clear how to fit them into 7 characters.
8. I haven't thought of anything else yet :)

Otherwise, I like it.

That's all. I'd be glad to hear your comments, as well as any suggestions for improvements.