Sidetone is audible feedback to someone speaking when using a handset or headset as an indication of an active transmission. Telephony In telephony, sidetone is the effect of sound picked up by the telephone's transmitter (mouthpiece) and instantly introduced at a low electronic signal level into the receiver (earpiece) of the same handset, a form of feedback . Sidetone in  19th century telephones varied until the carbon transmitter was used, which produced a distinct sidetone that discouraged speaking loudly enough, and occasionally so loud as to cause the instrument to produce uncontrolled oscillations, resulting in howling audio effects. Sidetone is disabled when phones of any kind are running in speakerphone mode, due to perpetual and almost immediate feedback. Anti-sidetone circuitry in the telephone hybrid brought sidetone under control in the early 20th century, leaving enough feedback signal to assure the user that the phone is really working, and allowing the use of a unitized telephone handset . In cellular technologies, one of the many benefits of sidetone-enabled phones is that a user knows a call has been dropped or ended if he or she no longer hears sidetone. Comfort noise provides a similar benefit.  Almost all land-line (wired and wireless) phones have employed sidetone, so naturally it was an expected convention for cellular telephony  but is not standard by any means . Usability experts believe that lack of adequate sidetone causes some people to shout or speak too loudly when using a cell phone (this behavior is sometimes referred to as "cell yell" ) . Sidetone is valuable for the hearing impaired. The amount of sidetone typically found on land-lines is  8\%, and is 4\% for cellular phones. Sidetone can be, and often is, amplified for land-line phones for the hearing impaired. In VOIP technologies such as Skype, sidetone has been experimented with but has not been formally adopted by software or hardware accessories creators . Several software packages and wiring workarounds have been developed that replicate sidetone, but feedback looping remains a problem.
Sidetone is audible feedback to someone speaking or otherwise producing sound as an indication of active transmission. Telephony In telephony, sidetone is the effect of sound picked up by the telephone's transmitter (mouthpiece) and instantly introduced at a low electronic signal level into the receiver (earpiece) of the same handset, a form of electrical feedback through the telephone hybrid . Sidetone in early 19th century telephones was strong due to the type circuit used in instruments. Anti-sidetone circuitry in the telephone hybrid brought sidetone under control in the early 20th century, leaving enough feedback signal to assure the user that the telephone is working . In cellular technologies, one of the many benefits of sidetone-enabled phones is that a user knows a call has been dropped or ended if he or she no longer hears sidetone. Comfort noise provides a similar benefit. Sidetone is disabled when telephones are running in speakerphone mode to prevent direct acoustical feedback from the speaker to the microphone, resulting in howling. Almost all land-line (wired and wireless) telephones have employed sidetone, so it was an expected convention for cellular telephony , but is not standard . Usability experts believe that lack of adequate sidetone causes some people to shout or speak too loudly when using a cell phone , a behavior that is sometimes referred to as "cell yell" . Sidetone is valuable for the hearing impaired. The amount of sidetone on land-lines is typically 8\%, and is 4\% for cellular phones. Sidetone can be, and often is, amplified for land-line phones for the hearing impaired. In Voice over IP technologies, such as Skype, sidetone implementation have been experimental . Several software applications and wiring workarounds have been developed that replicate sidetone, but feedback looping remains a problem.
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when using a handset or headset
or otherwise producing sound
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an
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feedback
electrical feedback through the telephone hybrid
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early
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varied until the carbon transmitter was used, which produced a distinct sidetone that discouraged speaking loudly enough, and occasionally so loud as to cause the instrument to produce uncontrolled oscillations, resulting in howling audio effects. Sidetone is disabled when phones of any kind are running in speakerphone mode, due to perpetual and almost immediate feedback.
was strong due to the type circuit used in instruments.
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phone is really working, and allowing the use of a unitized telephone handset
telephone is working
A
Sidetone is disabled when telephones are running in speakerphone mode to prevent direct acoustical feedback from the speaker to the microphone, resulting in howling.
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phones
telephones
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naturally
A
,
D
by any means
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(this behavior
, a behavior that
D
)
D
typically found
A
typically
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VOIP technologies
Voice over IP technologies,
D
has been experimented with but has not been formally adopted by software or hardware
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accessories creators
implementation have been experimental
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packages
applications