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Old 18th May 2019, 7:37 pm   #16
G6Tanuki's Avatar
Join Date: Apr 2012
Location: Wiltshire, UK.
Posts: 8,677
Default Re: GPO/BT Call Progress Tones?

In past-times the UK phone-network would include very short 'pips' of in-band audible tones for various signalling purposes during call-setup and cleardown.

Though these have not been used for a few decades, it's still quite common for the sound-effects-people in radio-dramas to include them in "calling someone on the phone" scenes.
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