TESTING ARRANGEMENT FOR A DATA COMMUNICATION SYSTEM

• US 3,721,958 A
• Filed: 04/30/1971
• Issued: 03/20/1973
• Est. Priority Date: 04/30/1971
• Status: Expired due to Term

• Current Assignee: Genicom Corp.
• Original Assignee: Robert P. Dixon
• Inventors: Dixon, Robert P.
• Primary Examiner(s): Atkinson, Charles E.
• Application Number:
  US05/138,999
• Time in Patent Office: 690 Days
• Field of Search: 340/146.1,146.1BA,146.1E 325/2,41,42,133 178/69H,69L
• US Class Current: 714/716
• CPC Class Codes: H04L 1/14 in which the signals are sent back to the transmitter to be checked ; echo systems

Abstract

The operation of a data communication system having a central transmitter and receiver and a data set transmitter and receiver, usually remotely positioned, can be tested by connecting a frequency converter between the data-set transmitter output and the data set receiver input so that signals from the central transmitter to the data set transmitter are returned by the data set receiver back to the central receiver. The data transmitted by the central transmitter can be compared with the data received by the central receiver to provide an indication of the operation of the data communication system.

Claims

1. An improved arrangement for testing the operation of a data communication circuit having a central transmitter for transmitting data and a central receiver for receiving data;

having a data set transmitter connected to said central transmitter for producing two frequencies fT and fT- Delta at an output in response to data from said central transmitter;

having a data set receiver connected to said central receiver for transmitting data to said central receiver in response to two frequencies fC and fC- Delta at an input; and

having a data set user circuit for connecting said data set transmitter output and said data set receiver input to a user line;

said improved arrangement comprising;

a. a frequency converter circuit having mixing means and an oscillator that produces a frequency fT + fC- Delta ;

b. means for selectively disconnecting said user line from said data set user circuit and connecting said frequency converter circuit to said data set user circuit so that said data set receiver is provided with the frequencies fC and fC- Delta in response to said data set transmitter producing the frequencies fT- Delta and fT respectively;

c. and means adapted to be connected to said central transmitter and receiver for comparing the data transmitted by said central transmitter with the data received by said central receiver after being transmitted through said data set transmitter and said data set receiver.

2. The improved testing arrangement of claim 1, wherein said means for selectively disconnecting said user line and connecting said frequency converter circuit can be operated remotely.

3. The improved testing arrangement of claim 1 wherein said comparison means are connected to the data input side of said central transmitter and to the data output side of said central receiver so that the comparison is made on the basis of the data itself.