Atomic Clock

My favorite Amazon purchase to date. Not difficult to set up and keeps time well. Easy to read since the decimals are large. I bought it for my laundry room so I know what time I leave and return.

Awesome product!! Works great. Easy to setup, super accurate received medium size display, and it found and locked into WWB signal in 10 minutes!! Highly recommend.

Great clock. Has large easy to read numerals. Easy to set up.

This is a nice clock. I think it works best as desk clock more than a wall clock, but other than that, I love it, and it gets the job done. The display is clear, and the numbers for the time are large and easily seen. It is basically a day clock, or some other light has to be on, in order to see it as it does not have a back display light.

nice and big. takes a day or so to sync, but after that, all good

I'll comment on two aspects of this clock: the atomic function and accuracy. Since it's sold as an 'atomic clock', I'll start with that. Atomicity ------------ I received this clock 12 days ago. I live in a top-floor apartment in a 3-floor building somewhere on the west coast of Los Angeles County, California; only around 880 miles from Fort Collins, Colorado. That's where the National Institute of Standards and Technology (NIST) broadcasts the 60kHz WWVB atomic-clock-based time radio signal. That signal has a 2000 mile radius and covers the entirety of the contiguous United States and reaches significantly large parts of Canada and Mexico. The building where I live doesn’t have a lot concrete or large metal structures; there isn’t a single tall building in the way between the clock and the low hills looming in the horizon; there’s no source of significant interference— powerful electric motors, high power lines… etc— nearby and the weather’s been beautiful those past 12 days. In short, as far as sight, I have clear near-line-of-sight to the source, and there’s nothing to cause poor reception. I’ve even used a compass and map to get the best directional cue after the first few failures. Yet, it seems a tall order for junk manufacturers to make products to receive the signal under these near-ideal conditions! I wonder if they even test their products in the US at all, the US being the only consumer, let alone test a statistically representative sample of locations within each state. First off, when I turned it on it, it did not receive the signal. I tried getting it to manually sync by pushing the WWVB button and waiting for it until it gives up— after 7 whole minutes, several times, including in the balcony, to no avail. It was very frustrating! Over the next three days I tried several spots and it would always fail, both manually and automatically. BTW, this clock and most of its ilk, like the not-as-bad 'Sharp' I purchased about 6 months ago, attempt to auto-sync several times late at night. According to this clock’s manual, it attempts the sync hourly for up to 3 times, starting at midnight. On the 4th day, I noticed that it had 'magically' synced. I noted the ‘sweet spot' where it did and kept it there until the 10th day. Throughout those 10 days, it was a hit-and-miss. However, it auto-synced in the ‘sweet spot' the last 3 days— of 10— in a row. On the 10th day, I noticed that time had jumped 40 minutes forwards, despite the indicated successful sync… just like that! And that's when I decided to return this piece of junk. Just for the sake of completeness, I found the ‘sweet spot' to be a tiny 2x2ft area on, and within a few inches off, a specific wall, and much lower than where one would normally hang a clock. Furthermore, manual syncing in the 'sweet spot' at an arbitrary time of day doesn’t work! So, it’s only auto-syncing that works, during the night, and only in the 'sweet spot!' Accuracy ----------- The magical 40-min jump aside, I noticed that without syncing it would gain nearly a full second daily (~0.9.) That's about 5.5 min ayear. The manual even specifies 'free run' accuracy as ± 60 seconds, per month! Is that acceptable from ANY timepiece in this day and age? I don't think so. It means this clock uses possibly the cheapest oscillator out there. In this regard, the 'Sharp' I already have loses— instead of gains— about 0.7 second per day; it uses a cheap oscillator too, just not as bad! Worse yet, even when it does sync, it doesn't correct the ~0.9 second it had gained the day before! It seems that it's either designed to ignore minor drifts, or the ~0.9 second drift is itself one of the, many, design flaws. Either way, what's the point of ‘atomicity’ when accuracy isn’t a design imperative? Notes ------- · The clock indicates successful syncing by the 3 curved lines (called “wave” in the manual) appearing above the fixed triangle (called “radio tower” therein.) · Gain and loss estimates are best-effort, and based on visual comparison with time display on a computer which syncs 3 times per day with NIST's NTP (Network Time Protocol) time servers. · The 'Sharp' I have has a similar 'spotty' syncing problem; it, too, has a poor WWVB radio receiver. Unfortunately, it worked somewhat acceptably in the place I was before, and my return window has closed many months ago. Apart from the weak receiver and oscillator unbecoming of the brand name, it's rather nice and sturdy, unlike this one. It supports up to 3 outdoor temperature sensors; it comes with only one, though. It's just not worth the $65 I paid Amazon for it, on account of the weak receiver. For reference, here it is: https://www.amazon.com/dp/B08S31FRDQ?ref=nb_sb_ss_w_as-reorder-t1_ypp_rep_k0_1_9&amp=&crid=YK3RQ60CQKOD&amp=&sprefix=sharp+ato · If you think you can live with manually setting clock, think again! This clock— and most of the ones of its ilk that I've checked out on Amazon— seem to have the design flaw of assuming it will successfully sync most of the time. Thus, their designers seem to pay little attention to how it will be set manually. There are only 2 buttons: Up and Down, to set just the hour and minute. The same butons are used to set other date components using the “Time Set” button to switch contexts. If you don't have nimble fingers and lighting-fast reflexes, you'll find it very trying to correctly adjust time to the second. And given how quickly in runs adrift, you'll probably have to go through that several times in a week. If you care for accuracy at all— as you should be if you're considering an atomic clock, you'll probably find it easier to just 'walk it' like a dog for up to half a mile to find a place where manual syncing succeeds! It's ironic really, it's a clock— an 'atomic clock', mind you— yet designed as if it were to be incorporated into a stove or microwave oven as a supplementary function!

Nice wall clock. Easy to view. Hard to see in low light as it doesn't light up.

Easy to setup. Put batteries in and wait for connection to satellite time. Put by a window (to the North) and it sets by itself. Accurate on all measurements. Just big enough not to be an eyesore, but easily read.

Clear and precise. Large enough to easiky see from 20 feet. Easy intutive to set.

Love the big screen and the backlight