Abstract: A system for analyzing a bi-directional communication path connecting a headend station to a remote station. The communication path is used for sending and receiving messages. Messages in a forward direction are sent by modulating a carrier at a forward frequency, and messages sent in a return direction are sent by modulating a carrier at a return frequency. The system includes a headend unit which sends a sign-on message in the forward direction from the headend station. The headend unit monitors the return frequency for a response message and measures a power level for signals received at the return frequency during the monitoring operation. The headend unit sends an error message in the forward direction if no response message is received on the return frequency, and the power level is greater than a threshold value. If an error message is sent, the power spectrum in a frequency range including the return frequency is measured and sent as part of the error message.

Abstract: A compact disc marking apparatus 10 comprising a top portion 12, a bottom portion 14 attached with a pivot or shaft 16 to the top portion 12, and a locking handle 18. A recess 12-2 receives the handle 18 when it is vertically rotated to a lowered position, when marking a disc. The bottom portion 14 comprises a first recess 14-1 and a second recess 14-2. The locking handle 18 comprises a lever member 18-1, an engaging/compression member 18-2, a flanged engaging member 18-3 (FIG. 2 ), a pivot 18-4 (FIG. 6 ), a flanged portion 18-5, and a rounded portion 18-6 (FIG. 9 ).

Abstract: A compact disc marking apparatus 10 comprising a top portion 12, a bottom portion 14 attached with a pivot or shaft 16 to the top portion 12, and a locking handle 18. A recess 12-2 receives the handle 18 when it is vertically rotated to a lowered position, when marking a disc. The bottom portion 14 comprises a first recess 14-1 and a second recess 14-2. The locking handle 18 comprises a lever member 18-1, an engaging/compression member 18-2, a flanged engaging member 18-3 (FIG. 2 ), a pivot 18-4 (FIG. 6 ), a flanged portion 18-5, and a rounded portion 18-6 (FIG. 9 ).

Abstract: A system for the remote visual inspection of a structure including two vessels, one disposed within the otherand defining an annulus therebetween. A guide member is provided circumferentially about an upper periphery of the two vessels. Mounted on the guide member are two motor-driven, diametrically opposed trolleys which support a flexible track member which extends downwardly through the annulus from one of the trolleys and back up the other side of the annulus to the other trolley. At least one motor-driven carrige is mounted on the track member and carries a camera and light source. By appropriate positioning of the trolleys and the carriage, all the surfaces of the vessels defining the annulus are accessible for visual inspection by the camera. In accordance with a particular preferred embodiment, markers are placed at preselected points in the annulus on one of the vessels to permit verification of the location of the camera and carriage.