Editing Baby monitor

{{Short description|Radio system for remotely listening to a child}}
{{needs more sources|date=March 2022}}
[[Image:Babymonitor.JPG|thumb|230px|Audio baby monitor]]
A '''baby monitor''', also known as a '''baby alarm''', is a [[radio]] system used to remotely listen to sounds made by an [[infant]]. An audio monitor consists of a transmitter unit, equipped with a [[microphone]], placed near to the child.  It transmits the sounds by [[radio wave]]s to a receiver unit with a [[loudspeaker|speaker]] carried by, or near to, the person caring for the infant. Some baby monitors provide [[two-way communication]] which allows the parent to speak back to the baby (parent talk-back). Some allow music to be played to the child. A monitor with a video camera and receiver is often called a ''baby cam''.

One of the primary uses of baby monitors is to allow attendants to hear when an infant wakes, while out of immediate hearing distance of the infant. Although commonly used, there is no evidence that these monitors prevent [[Sudden infant death syndrome|SIDS]], and many doctors believe they provide a false sense of security.<ref>{{cite web|title=Antenatal care – information and advice.|url=http://www.bupa.co.uk/health-information/directory/a/antenatal-care|website=www.bupa.co.uk|access-date=28 November 2016|archive-date=15 February 2017|archive-url=https://web.archive.org/web/20170215073029/http://www.bupa.co.uk/health-information/directory/a/antenatal-care|url-status=live}}</ref> Infants and young children can often be heard over a baby monitor in [[crib talk]], in which they talk to themselves. This is a normal part of practising their language skills.

==History==

The first baby monitor was the [[Zenith Radio Nurse]] in 1937. This [[Zenith Radio]] product was developed by [[Eugene F. McDonald]], and designed by Japanese-American sculptor and product designer [[Isamu Noguchi]].<ref>{{cite web|last=Onion|first=Rebecca|title=The World's First Baby Monitor: Zenith's 1937 "Radio Nurse"|url=http://www.slate.com/blogs/the_vault/2013/02/07/zenith_s_radio_nurse_designed_by_isamu_noguchi_was_the_world_s_first_baby.html|work=[[Slate (magazine)|Slate]]|date=7 February 2013|publisher=[[The Slate Group]]|access-date=7 February 2013|archive-date=11 August 2018|archive-url=https://web.archive.org/web/20180811185027/http://www.slate.com/blogs/the_vault/2013/02/07/zenith_s_radio_nurse_designed_by_isamu_noguchi_was_the_world_s_first_baby.html|url-status=live}}</ref>

==Video baby monitors (baby cams)==
Some baby monitors also use a video camera to show pictures on the [[receiver (radio)|receiver]], either by plugging the receiver into a television or by including a portable [[LCD]] screen. This type of [[surveillance camera]] is often called a ''baby cam''.

Some baby cams can work at night with low light levels. Most video baby monitors today have a night vision feature. [[Infrared]] [[Light-emitting diode|LEDs]] attached on the front of the camera allow a user to see the baby in a dark room. Video baby monitors that have night vision mode will switch to this mode automatically in the dark. Some advanced baby cams now work over Wi-Fi so parents can watch babies through their smartphone or computer.

Baby monitors continue to evolve and now also can utilize features such as night lights and built-in lullabies. These are not available in all monitors. Some include temperature and movement monitoring devices to sit underneath a mattress or close to the baby within a cot.

==Movement monitors==
A baby movement monitor uses sensor pads placed under the crib mattress to detect movement, if movement stops for more than 20 seconds an alarm will sound.

==Wired and wireless==
Baby monitors generally use wireless systems, but can also use wires or may operate over [[Power line communication|existing household wiring]] such as [[X10 (industry standard)|X10]].

Wireless systems use [[Radio spectrum|radio frequencies]] that are designated by governments for unlicensed use. For example, in North America frequencies near 49 [[hertz|MHz]], 902&nbsp;MHz or 2.4&nbsp;GHz are available. While these frequencies are not assigned to powerful television or radio broadcasting transmitters, [[Electromagnetic interference|interference]] from other wireless devices such as [[cordless telephone]]s, [[Radio control|wireless toys]], [[Wireless LAN|computer wireless networks]], [[radar]], [[Smart meter|Smart Power Meters]] and  [[microwave oven]]s is possible.

Digital audio wireless systems using [[Digital Enhanced Cordless Telecommunications|DECT]], are resistant to interference and have a range up to 300 m.<ref>{{cite web|title=Philips Babycare|url=http://www.babycare.philips.com/GB/en/index2.html|access-date=28 November 2016}}{{Dead link |date=June 2017}}</ref>

Analog audio transmissions can be picked up at a distance from the home by a [[Scanner (radio)|scanner receiver]] or other baby monitor receivers, and so present a risk to privacy as long as the transmitter is switched on. Digital transmission such as [[Frequency-hopping spread spectrum]] provides a level of protection from casual interception.

Some wireless baby monitors support multiple cameras on one handheld monitor-receiver. These systems are even compatible with a standard [[wireless security camera]].

[[FM transmitter (personal device)|FM transmitter]]s, paired with a [[microphone]] can be an inexpensive solution to a DIY baby monitor, since [[clock radio]]s can also be used as one.

==Smartphone as baby monitors==
Smartphone [[Application software|apps]] allow a user to monitor a camera-equipped device, such as another smartphone or a tablet. Alternatively, [[Wi-Fi]] or [[Bluetooth]] can link a camera to a dedicated app on a smartphone or tablet.  This means a smart device doesn't need to be left in the baby's room.

==Other features ==
Portable battery-operated receivers can be carried by the parent around the house. The transmitter stays near the infant crib and is usually plugged into a [[Domestic AC power plugs and sockets|AC socket]]. Some baby monitor packages include two receivers.

Baby monitors may have a visible signal as well as repeating the sound.  This is often in the form of a set of lights to indicate the noise level, allowing the device to be used when it is inappropriate or impractical for the receiver to play the sound. Other monitors have a [[vibrating alert]] on the receiver making it particularly useful for people with hearing difficulties.

Systems with several transmitters can monitor several rooms in the home at once.

Transmitters with movement sensors such as a pressure-sensitive mat placed beneath the child's mattress give additional warning of restless activity by the infant.

==Standards==
The new voluntary [[ASTM|ASTM International]] F2951 [[International standard|standard]] has been developed to address incidents associated with strangulations that can result from infant entanglement in the cords of baby monitors. This standard for baby monitors includes requirements for audio, video, and motion sensor monitors. It provides requirements for labeling, instructional material and packaging and is intended to minimize injuries to children resulting from normal use and reasonably foreseeable misuse or abuse of baby monitors.

==Privacy ==
Signals of baby monitors can be received by third parties, presenting privacy issues.<ref>{{cite web|url=https://www.theregister.co.uk/2018/06/22/baby_monitor_hacked/|title=Don't panic, but your baby monitor can be hacked into a spycam|website=[[The Register]]|access-date=2018-06-23|archive-date=2018-06-23|archive-url=https://web.archive.org/web/20180623141303/https://www.theregister.co.uk/2018/06/22/baby_monitor_hacked/|url-status=live}}</ref>

==See also==
* [[Digital Enhanced Cordless Telecommunications]] (DECT), standard for encrypted cordless telephony developed by ETSI, used in some baby monitors
* [[Frequency-hopping spread spectrum]] (FHSS), unencrypted transmission method based on pseudo-random frequency hops, used in some baby monitors
* [[Nanny cam]], spy camera used to secretly monitor home caregivers
* [[Spy video car]], hybrid product created by mixing a traditional radio-controlled car and a video baby monitor
* [[Title 47 CFR Part 15]], U.S. regulation allowing unlicensed radio use in wireless consumer electronics

==References==
{{Reflist}}

{{Child safety devices}}
{{Authority control}}

[[Category:Babycare]]
[[Category:Consumer electronics]]
[[Category:Infancy|Monitor]]
[[Category:American inventions]]
[[Category:20th-century inventions]]