KGTV 10 News in delay?

[Eat News 4738]

Here is a mystery ...blame RKO for getting me on this path...

 

I was playing around with an antenna Tv when I noticed that there is a six second delay between the KGTV-DT 10-1 OTA signal, and the COX cable signal. The METV feed off the same transmitter and thru COX is only one half a second or less. Same with my other channels locally...all under 1/2 second delay for the signal processing at the head-end thru the chain.

 

What gives ?

Six seconds is a lifetime to process that signal in this portion of the planet. You can feed thru fiber and sats and still get in under 6 seconds in this hemisphere.

 

It's not a show delay, because we would not see that unless we had access to a realtime feed or IFB channel.

 

Anyone else notice extra long delay between the CATV and OTA signals of your local stations?

 

I'm going OCD over this already

[Eat News 4738]

Here is a mystery ...blame RKO for getting me on this path...

 

I was playing around with an antenna Tv when I noticed that there is a six second delay between the KGTV-DT 10-1 OTA signal, and the COX cable signal. The METV feed off the same transmitter and thru COX is only one half a second or less. Same with my other channels locally...all under 1/2 second delay for the signal processing at the head-end thru the chain.

 

What gives ?

Six seconds is a lifetime to process that signal in this portion of the planet. You can feed thru fiber and sats and still get in under 6 seconds in this hemisphere.

 

It's not a show delay, because we would not see that unless we had access to a realtime feed or IFB channel.

 

Anyone else notice extra long delay between the CATV and OTA signals of your local stations?

 

I'm going OCD over this already

 

Why does this matter?

 

Because KGTV often has call-in contest where you need to be caller #(?) to the special contest phone number.

If I have a 6 second lead over the other contestants because I'm watching OTA...

 

That could be called "rigging a contest".

[rkolsen 1679]

So the OTA signal is faster? Maybe for some reason Cox is receiving the signal OTA rather than direct microwave or fiber. They'd have to decode and transcode it for their format. HD uses more bits than SD. But it's a bit puzzling.

 

Now is there a delay from the OTA HD feed to the SD feed on Cox?

 

I can't measure delay here in Baltimore for comparison purposes (both Scripps owned ABC affiliates - hopefully they have the same equipment at the station for encoding) despite being 8 miles from TV Hill. I can't pull in the signal. I mentioned it before but my home backs to a hill, with homes on top of the hill and tall trees. The only signal I could ever pull in was WGAL from 40-50 miles away.

[Eat News 4738]

So the OTA signal is faster? Maybe for some reason Cox is receiving the signal OTA rather than direct microwave or fiber. They'd have to decode and transcode it for their format. HD uses more bits than SD. But it's a bit puzzling.

 

Now is there a delay from the OTA HD feed to the SD feed on Cox?

 

I can't measure delay here in Baltimore for comparison purposes (both Scripps owned ABC affiliates - hopefully they have the same equipment at the station for encoding) despite being 8 miles from TV Hill. I can't pull in the signal. I mentioned it before but my home backs to a hill, with homes on top of the hill and tall trees. The only signal I could ever pull in was WGAL from 40-50 miles away.

 

The OTA comes first...and the COX cable signal hits me 6 seconds later...all the others are 1/2 sec max.

 

Where is this signal spending 5-1/2 seconds?

 

I suppose they COULD be shooting up to the(a) bird first...and COX is down linking. But that would not make any sense, why would anyone do that?

[Eat News 4738]

The OTA comes first...and the COX cable signal hits me 6 seconds later...all the others are 1/2 sec max.

 

Where is this signal spending 5-1/2 seconds?

 

I suppose they COULD be shooting up to the(a) bird first...and COX is down linking. But that would not make any sense, why would anyone do that?

 

and the other sub channels METV 10-3 and LAFF 10-2 are all at 1/2 sec....not 6 seconds...just the 10-1 carrier.

[Surplus Engineer 38]

The OTA comes first...and the COX cable signal hits me 6 seconds later...all the others are 1/2 sec max.

 

Where is this signal spending 5-1/2 seconds?

 

I suppose they COULD be shooting up to the(a) bird first...and COX is down linking. But that would not make any sense, why would anyone do that?

 

It's not shooting to any bird. It's signal processing and different equipment in the air chain, especially anything having to do with compression. Depending on how they have it set up, it can add quite a bit of latency. Encoders, either before or after the STL, are your likely culprit.

 

I know of at least one station that has more than 10 seconds of delay from the time the source is switched in master to when it is received back from the transmitter on a demod. And that's just because they're compressing the begeezus out of it before it hits the STL. They're trying to shoehorn a full 1080i stream and 3 or 4 SD streams into the same little slice of bandwidth. That doesn't happen instantly.

[Eat News 4738]

It's not shooting to any bird. It's signal processing and different equipment in the air chain, especially anything having to do with compression. Depending on how they have it set up, it can add quite a bit of latency. Encoders, either before or after the STL, are your likely culprit.

 

I know of at least one station that has more than 10 seconds of delay from the time the source is switched in master to when it is received back from the transmitter on a demod. And that's just because they're compressing the begeezus out of it before it hits the STL. They're trying to shoehorn a full 1080i stream and 3 or 4 SD streams into the same little slice of bandwidth. That doesn't happen instantly.

 

And then you add my local cable head-end..and it's off to the races again.

 

Those delays must really play hell on the audio.

 

Thanks for the reply.

[Surplus Engineer 38]

And then you add my local cable head-end..and it's off to the races again.

 

Those delays must really play hell on the audio.

 

Thanks for the reply.

 

If you mean playing havoc on lip sync, then it shouldn't as long as they don't do anything dumb like de-embed and re-embed. It's not like the old analog days where the video and audio were two separate signals travelling together. It's all part of the same set of bits. That does remind me though that another source of delay is the CALM compliance equipment.