Black box (phreaking)
id:
black-box-phreaking-285-5017388
title:
Black box (phreaking)
text:
Black boxes were devices which, when attached to home phones, allowed all incoming calls to be received without charge to the caller. The black box was a small electronic circuit, usually a resistor or zener diode in series with the line. It relied on (now-obsolete) telephone exchanges controlled by mechanical relays. These exchanges used a relay to detect a drop in line voltage to begin billing for a call; a separate relay controlled ringing on the line. The black box placed a resistor in serie
brand slug:
wiki
category slug:
encyclopedia
description:
Electronic device to avoid phone charges
original url:
https://en.wikipedia.org/wiki/Black_box_(phreaking)
date created:
date modified:
2024-02-19T17:43:44Z
main entity:
{"identifier":"Q2905331","url":"https://www.wikidata.org/entity/Q2905331"}
image:
fields total:
13
integrity:
14