Jumbl™ Digital LCD Travel Alarm Clock Review
- 10 years ago
First, the big question: Does the clock work? The answer is yes, and since I filled the water reservoir with tap water several days ago, the clock has been very accurate. Setting the time and calendar were simple and straightforward. Setting the alarm is very simple, but the sound of the alarm is too weak to wake most people up. The temperature display is very accurate, according to my own thermometer. Note that the display is not backlit, so it's only readable with some ambient light.
Making a clock powered by water is a clever idea that makes for a nice "show and tell" piece. I wondered what really makes it work, and the best answer I found was this: "Water-powered clocks run off a simple galvanic cell battery, which involves the immersion of a cathode or positive metal (such as copper) and an anode or negative metal (such as zinc) in an electrolyte solution. The ion-filled water (from dissolved minerals in tap water) serves as the electrolyte solution, which allows the transfer of electrons between the two metals, resulting in an electric cell." If you're interested in this, I recommend you google "galvanic cell."
The instructions mention that periodically the two metal plates will need to be cleaned with a water-vinegar solution. I found different opinions online about whether the metal plates ever need to be replaced and if so, how often. It's been fifty years since I studied chemistry, but I think that one of the plates will eventually disappear, with its metal ions being deposited on the other plate.
As an accurate clock and a curiosity piece, I would give the water powered clock 5 stars, but because of the very weak-sounding alarm, I have to deduct one star. If you don't need the alarm, it's not an issue.
Get Sale Price On Amazon:
http://amzn.to/1qHE2BH
Making a clock powered by water is a clever idea that makes for a nice "show and tell" piece. I wondered what really makes it work, and the best answer I found was this: "Water-powered clocks run off a simple galvanic cell battery, which involves the immersion of a cathode or positive metal (such as copper) and an anode or negative metal (such as zinc) in an electrolyte solution. The ion-filled water (from dissolved minerals in tap water) serves as the electrolyte solution, which allows the transfer of electrons between the two metals, resulting in an electric cell." If you're interested in this, I recommend you google "galvanic cell."
The instructions mention that periodically the two metal plates will need to be cleaned with a water-vinegar solution. I found different opinions online about whether the metal plates ever need to be replaced and if so, how often. It's been fifty years since I studied chemistry, but I think that one of the plates will eventually disappear, with its metal ions being deposited on the other plate.
As an accurate clock and a curiosity piece, I would give the water powered clock 5 stars, but because of the very weak-sounding alarm, I have to deduct one star. If you don't need the alarm, it's not an issue.
Get Sale Price On Amazon:
http://amzn.to/1qHE2BH