This report is about a Thesis for Degree of Bachelor of Science at Linköping University. It describes design of equipment which makes it possible to measure signal and noise quality during data transmission via Asymmetric Digital Subscriber Line, ADSL. The measuring instrument is HP 4934A Transmission Impairment Measuring Set. The equipment was supposed to be used for testing of ADSL systems within Solectron Sweden AB. In fact, the equipment stands for virtual Plain Old Telephone Service, POTS. That is why it simulates all three states that may come up. The states are following:"on hook", ringing,"off hook"(speech transmission). There is a control unit in the design. It changes between different circuit connections to get one of the states. You have to use a computer for control of the equipment. The computer commands are sent to equipment via its serial port via RS232 to the control unit. The equipment is driven with 48 Vdc.

<p>This report is about a Thesis for Degree of Bachelor of Science at Linköping University. It describes design of equipment which makes it possible to measure signal and noise quality during data transmission via Asymmetric Digital Subscriber Line, ADSL. The measuring instrument is HP 4934A Transmission Impairment Measuring Set. The equipment was supposed to be used for testing of ADSL systems within Solectron Sweden AB. In fact, the equipment stands for virtual Plain Old Telephone Service, POTS. That is why it simulates all three states that may come up. The states are following:"on hook", ringing,"off hook"(speech transmission). There is a control unit in the design. It changes between different circuit connections to get one of the states. You have to use a computer for control of the equipment. The computer commands are sent to equipment via its serial port via RS232 to the control unit. The equipment is driven with 48 Vdc.</p>