This analyzer replays a stream of diverse 5G NR SS/PBCH blocks in your browser, no server and no radio attached. Each block is decoded to its Master Information Block and checked bit-exact against what was transmitted. The stream runs the receiver across the full parameter space and a worsening channel: the constellation is a tight QPSK when the signal is clean, spreads as the SNR falls, and collapses to a red noise cloud at the coding limit, where the CRC finally fails. The vectors come from the same host decode chain that runs on the KV260 front-end spectra. Every number is measured, not simulated for show.