[time-nuts] Measuring TV delays

[Glenn Little]

Typically, cable receives the signal off air or via fiber.
They decode the digital signal to baseband.
They reencode the signal to their distribution format.
They mux all the channels together.
All of this is transmitted as packets.
Each channel has a PID assigned in the header of the  packet.
Your TV or set top box decodes the packets and displays the ones for 
the channel that you have selected.

The decode and encode time at the cable plant is part of this.
Most of the latency is that you would not pay for a fast enough 
processor in your TV or set top box to process all of the packets faster.

The more channels in the cable system, the longer the latency.

73
Glenn
WB4UIV



At 08:31 AM 1/2/2014, you wrote:
>Cable here had about a 10 second latency. HNY - Mike
>
>Mike B. Feher, EOZ Inc.
>89 Arnold Blvd.
>Howell, NJ, 07731
>732-886-5960 office
>908-902-3831 cell
>
>
>_______________________________________________
>time-nuts mailing list -- time-nuts at febo.com
>To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>and follow the instructions there.