Hidden pids, we've all seen this, but on ATSC?

Kinda cool but was playing around with 13-1 (CITYTV-HD) here in Edmonton and noticed a PID with 4Mbit/sec data on it, enough for SD video, and two pids right below it that had enough for audio. But they weren't listed in the PMT/PAT so I tried them. Tada a SD feed of the same video as the HD feed.

Thought it was kinda cool as I hadn't seen it before on ATSC

UDL

Forum: Computer and USB Satellite Receivers and Recording