05161182 is referenced by 16 patents and cites 10 patents.

A remote meter reading system has equipment at a telephone company office coupled by modems to a utility company computer which issues requests for customer data. Telephone test trunks are used to access individual meter sites and initiate meter readings using a number of single frequency bursts. Meter sending units emit a pulse for each unit of consumption and a microprocessor counts the pulses in RAM to derive separate meter readings. When interrogated, the microprocessor outputs the readings in a binary coded decimal format to a DTMF tone generator which emits each decimal number as a tone pair which is transmitted via the telephone line and is detected at the telephone company, translated into ASCII code and transmitted by modem to the utility computer.

Title
Remote meter reading method and apparatus
Application Number
333117
Publication Number
5161182
Application Date
April 17, 1991
Publication Date
November 3, 1992
Inventor
Bryan F Scott
Rio Rancho
NM, US
Dale L Scott
Albuquerque
NM, US
David P Merriam
Albuquerque
NM, US
Agent
Reising Ethington Barnard Perry & Milton
Assignee
Sparton Corporation
MI, US
IPC
H04M 11/00
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