Trilithic’s 860 DSPi field analyzer now includes a vertical-interval-test-signal (VITS) option. This option enables convenient head-end measurements on installed cables. With the VITS option, it is possible to view the test signals, which are inserted during the vertical-synchronization interval of analog video, and specify lines for testing. The option enables the measurement of differential gain, differential phase, chroma-delay, and in-channel response. This is a firmware option, making retrofitting as simple as entering a purchased code key.