The SDA-5000 (with OPT 1 installed) allows simple and practical testing of the reverse path frequency response, regardless of the frequency (5 to 1000 MHz). And the SDA has a built-in reverse sweep transmitter, which means externally generated carriers are not required. Furthermore, the SDA-5500 transmitter and field receivers have frequency agile telemetry. They can be configured to communicate on both the forward and reverse paths. Forward (downstream) and reverse (upstream) path alignment can be performed simultaneously by one person. The operator simply indicates which screen should be displayedTonethe response from the headend to the test point, or the response from the test point to the headend. A reverse sweep can uncover mismatch problems, which reveal themselves as standing waves, or duplex filter roll-offs that can severely hamper the quality of services in the reverse band.