by Turbo_Hobby
Price: 35 SGD ~ $25 USD / eBay buy-in-now
I just got my SZ-8 clock in the mail and I am excited to review it for you. Shipping from Singapore took about two and a half weeks but that isn't too surprising considering that it had to clear US Import Customs. (I originally posted about the clock here. )
For disclosure, this clock was not sent to me for review. I discovered it on eBay by accident and purchased a unit for my own collection. All of the photos and video in this review are mine.
One of the stand out features of this clock is that it only has one digit. That might be an obvious statement but it is a little unusual. The time is displayed by displaying the digits in HHMM order. There is a brief pause between the numbers and a longer pause once it is finished. You can see this in the video. To make reading easier, there are four yellow LED's which indicate which digit is being displayed. While I have only had the clock for a short while, I already prefer having the yellow indicators on.
Setting the clock is a bit of a pain. This is primarily because it didn't ship with any instructions. When the clock first powers on, it displays every digit once, presumably as a power on self test. Once that is done, the LEFT button turns on and off the yellow indicators. To set the time, turn on the yellow indicators - this will make your job much easier. The clock has already started cycling through the digits. When it gets to a digit you want to change, hit the RIGHT button. The clock will freeze and you can keep pressing the right button to increment the digit to the correct value. Wait for a few seconds and the clock will resume. Repeat this for each digit. You do not set the hour as "12" - you set the first digit to 1 and the second digit to 2. The clock is in 24h mode so keep that in mind when setting it after lunch.
The clock is powered via USB. There is a mini-USB (NOT Micro) on the left side of the unit. I really appreciate the fact that this device does not use a wall adapter. As any gadget lover knows, there are never enough outlets around. By using USB, you can simply plug it in to your computer or any USB wall charger if you want. The extra flexibility that this creates is great. For example, I have my device powered by the USB out on my Epoch Clock and it seems to work fine. Thankfully, this device includes a battery backup - the big black circle on the back of the unit. This should prevent you from having to reset the clock every time the power goes out.
I haven't had the clock long enough to measure drift. I don't intend to do formal measurements of this.
The tube itself is somewhat unusual. It is an SZ-8 which appears to be a clone of a Z560M tube. The letters are surprisingly "fat" but easily readable. The tubes are not new but they do not show any obvious signs of use. There is no evidence of cathode poisoning and don't appear to be any defects in the tube. Additionally, the seller included a spare tube in case the original one breaks/dies/etc. I do unsure if these tubes contain mercury. They don't have the typical blue/violet glow like an IN-18 does so I am inclined to say they they do not. (Mercury helps prolong the lifespan of the tube.)
The clock is smaller than an average smartphone. It is about four inches tall by two inches wide. It is about an inch and a half deep, largely because of the tube. There are four standoffs that are included which would help with mounting if you want to build a custom frame. It does not, however, come with an enclosure. This is my single biggest complaint about the device. You probably won't be harmed if you touch the power supply but you might feed a bit of a shock. I haven't tried so I can't say for sure, but 180v would probably be noticeable. There is very little current so I highly doubt it would be anything more than a tingle. The other problem that the lack of a case produces is that the clock doesn't want to stand vertically on its own. It is top heavy because of the tube and the USB cord on the left means that it is constantly falling over. I have mine wedged on my desk to prevent it from falling, but an enclosure or sturdy base would solve this.
Overall I really like this device. When he produces more, go buy one. At $25 USD, you can't go wrong. All of my complaints are minor and I doubt you could even build one of these clocks for cheaper. I had a positive experience buying from Turbo_Hobby and would not hesitate to buy from him again.
Verdict: Buy It
Pros
- USB Powered
- Clean PCB layout
- Battery Backup
- Inexpensive
- Well built
- Unusual display
Cons
- Top heavy design means it falls over frequently
