The Homedics SoundSpa Digital FM Tabletop Clock with time projection gives you the power to create a soothing, relaxing sleep environment. Choose from eight peaceful relaxation sounds including ocean, white noise, brook, rainforest, thunder, rain, fan, campfire, or simply switch on the radio. The SoundSpa Digital FM Tabletop Clock comes with the option of time projection and a soothing blue light.
The Howard Miller Chaz 625-614 Contemporary Wall Clock is finished in a Satin Silver on select hardwoods and veneers. This clock features insert mirror panels accenting the fixed front frame. The white dial has polished chrome bar hour markers and hands. The rectangle cut-out reveals a polished chrome-finished pendulum bob. The Chaz features a accurate Quartz, battery-operated, single-chime movement that plays the Westminster chime on the hour and counts the hour. It also features Automatic nighttime chime shut-off. Requires four AA sized batteries (not included). One Year Warranty and Free Shipping.
This Roman Numerals Vintage Wall Clock makes telling time easier on the eyes. The clock’s backing is made to look like aged barnwood. It has black metal framing and large Roman Numerals on its dial cut from the same black painted metal. Silver studs dot the frame wherever the numerals join it for a striking, yet simple, accent. The hands of the clock are metal too, telling the time with a minute and hour hand. This stunning Roman Numerals Vintage Wall Clock really strikes a chord for home...
Pairing a simple design with a contrasting black-and-silver palette, this eye-catching 12" wall clock instantly elevates your favorite aesthetic. Its round silhouette blends effortlessly into both casual or formal spaces, while its clean profile adds sophistication to your decor. Lean into this wall clock's versatility by adding it to a transitional living room arrangement alongside a mid-century-inspired sofa and gently-tufted barrel chairs for a cohesive seating space. Anchor the ensemble...
It’s vital to your personal health. When you rest at night, after about twenty to thirty minutes, your body begins to enter REM sleep (if you’re lucky). Either way, your body slows down. Your heart rate hits around 40-50 BPM when you’re sleeping, compared to the 60-100 BPM you go through while you’re awake. This gives your body time to give your heart a rest, repair blood vessels, and repair muscle tissue if you worked out, or physically strained yourself during the day.
Many devices can be used to mark passage of time without respect to reference time (time of day, minutes, etc.) and can be useful for measuring duration or intervals. Examples of such duration timers are candle clocks, incense clocks and the hourglass. Both the candle clock and the incense clock work on the same principle wherein the consumption of resources is more or less constant allowing reasonably precise and repeatable estimates of time passages. In the hourglass, fine sand pouring through a tiny hole at a constant rate indicates an arbitrary, predetermined, passage of time. The resource is not consumed but re-used.
A silent instrument missing such a striking mechanism has traditionally been known as a timepiece. In general usage today, a "clock" refers to any device for measuring and displaying the time. Watches and other timepieces that can be carried on one's person are often distinguished from clocks. Spring-driven clocks appeared during the 15th century. During the 15th and 16th centuries, clockmaking flourished. The next development in accuracy occurred after 1656 with the invention of the pendulum clock. A major stimulus to improving the accuracy and reliability of clocks was the importance of precise time-keeping for navigation. The electric clock was patented in 1840. The development of electronics in the 20th century led to clocks with no clockwork parts at all.
In a master clock system, electricity is used to give direct impulses to the pendulum, which in turn causes the clock’s gear train to move, or to lift a lever after it has imparted an impulse to the pendulum. In various modern master clocks the pendulum operates a light count wheel that turns through the pitch of one tooth every double swing and is arranged to release a lever every half minute. This lever gives an impulse to the pendulum and is then restored to its original position by an electromagnet. The pulse of current that operates the electromagnet can also be transmitted to a series of distant dials, or slave clocks, advancing the hands of each through the space of a half minute. Thus, a master clock can control scores of dials in a large group of buildings, as well as such other apparatus as time recorders and sirens.
Besides the Chinese astronomical clock of Su Song in 1088 mentioned above, in Europe there were the clocks constructed by Richard of Wallingford in St Albans by 1336, and by Giovanni de Dondi in Padua from 1348 to 1364. They no longer exist, but detailed descriptions of their design and construction survive, and modern reproductions have been made. They illustrate how quickly the theory of the mechanical clock had been translated into practical constructions, and also that one of the many impulses to their development had been the desire of astronomers to investigate celestial phenomena.
Electric clocks that are powered from the AC supply often use synchronous motors. The supply current alternates with a frequency of 50 hertz in many countries, and 60 hertz in others. The rotor of the motor rotates at a speed that is related to the alternation frequency. Appropriate gearing converts this rotation speed to the correct ones for the hands of the analog clock. The development of electronics in the 20th century led to clocks with no clockwork parts at all. Time in these cases is measured in several ways, such as by the alternation of the AC supply, vibration of a tuning fork, the behaviour of quartz crystals, or the quantum vibrations of atoms. Electronic circuits divide these high-frequency oscillations to slower ones that drive the time display. Even mechanical clocks have since come to be largely powered by batteries, removing the need for winding.
In atomic clocks the controller is an evacuated microwave cavity attached to a microwave oscillator controlled by a microprocessor. A thin gas of caesium atoms is released into the cavity where they are exposed to microwaves. A laser measures how many atoms have absorbed the microwaves, and an electronic feedback control system called a phase-locked loop tunes the microwave oscillator until it is at the frequency that causes the atoms to vibrate and absorb the microwaves. Then the microwave signal is divided by digital counters to become the clock signal.
An alarm clock (alarm for short) is a clock that is designed to alert an individual or group of individuals at specified time. The primary function of these clocks is to awaken people from their night's sleep or short naps; they are sometimes used for other reminders as well. Most use sound; some use light or vibration. Some have sensors to identify when a person is in a light stage of sleep, in order to avoid waking someone who is deeply asleep, which causes tiredness, even if the person has had adequate sleep. To stop the sound or light, a button or handle on the clock is pressed; most clocks automatically stop the alarm if left unattended long enough. A classic analog alarm clock has an extra hand or inset dial that is used to specify the time at which to activate the alarm. Alarm clocks are also found on mobile phones, watches, and computers.
“This alarm clock will wake you up! I’m totally deaf in one ear and partially deaf in the other. Alarm clocks I used before I purchased this one might as well have been turned off if I happened to have my good ear on the pillow when they went off. This one is loud! Now having said that, its loudness is adjustable, and I found that a low setting of two works just fine for me, but if I am particularly concerned about being awakened, I also set the vibrating disk, which is slipped under the mattress. Believe me: Even if you are totally deaf in both ears, this will wake you up. I was skeptical about the vibrator because I have a thick mattress, but it works with no problem at all! I wholeheartedly recommend this alarm clock for anyone who is hearing impaired.”