Precise tone plan
id:
precise-tone-plan-245-8408619
title:
Precise tone plan
text:
The precise tone plan is a signaling specification for the public switched telephone network (PSTN) in North America. It defines the call-progress tones used for indicating the status and progress of telephone calls to subscribers and operators. All signals in the specification use combination of audible tones of four frequencies: 350 Hz, 440 Hz, 480 Hz, and 620 Hz. Equipment is required to maintain tolerances within ± 0.5% in frequency and ±1.5 dB in amplitude stability. Harmonic distortion is
brand slug:
wiki
category slug:
encyclopedia
description:
Signalling specification for telephony
original url:
https://en.wikipedia.org/wiki/Precise_tone_plan
date created:
date modified:
2021-10-09T22:13:53Z
main entity:
{"identifier":"Q7239506","url":"https://www.wikidata.org/entity/Q7239506"}
image:
fields total:
13
integrity:
14