05121342 is referenced by 103 patents and cites 5 patents.

A handheld, battery operated network testing device uses disk loaded software, programmable gate arrays, and digital signal processing to selectively configure the device for a full range of analog and digital testing modes in a variety of communications protocols, including T-1 full duplex drop and insert. A 25 by 80 column LCD display provides for a full scale video output, and a unique, power efficient, electroluminescent backlight circuit provides for viewing of the display in poorly lit environments.

Title
Apparatus for analyzing communication networks
Application Number
7/399743
Publication Number
5121342
Application Date
August 28, 1989
Publication Date
June 9, 1992
Inventor
Lonnie J Helgeson
Jordan
MN, US
Tracy Clark
Bloomington
MN, US
Shawn P Finnegan
Mendota Heights
MN, US
Jeffrey D Mullin
Roseville
MN, US
Kenneth D Gjerde Jr
Minneapolis
MN, US
Robert C Szymborski
Bloomington
MN, US
Agent
Dorsey and Whitney
Assignee
Network Communications Corporation
MN, US
IPC
G06F 15/16
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