HP 30242 Installation And Service Manual page 46

Principles of Operation
JABBER FAULT DETECTION. If the LANIC should try to send data for a time longer than the longest
data packet allowed, the network throughput could be affected. (If the LANIC transmitted continuously,
no other node could access the network.) The jabber fault detection circuitry detects any attempt by the
MAD to transmit for longer than 25 milliseconds, and prevents this from happening by turning the
transmitter off permanently. The LANIC is informed of the shut-off condition by a continuous signal
(SQE) on the CI pair of the AUI cable. The MAU is prevented from transmitting until it is powered off
and then on again.
Feb 85
3-20