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post #11881 of 11909 Old 03-03-2015, 01:06 AM
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Quote:
Originally Posted by SFischer1 View Post
I am having a horrible delay with page 396 of this thread.
SHF
I've had a few times lately where it taken some time to connect to AVS, but I haven't noticed any delay once I'm connected, including page 396. Wonder what's causing the problem.

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post #11882 of 11909 Old 03-03-2015, 08:35 AM
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[QUOTE=SFischer1;32271337]KFSF went off the air ~ 6 AM it appears.

Check Toast0's chart for outages over a hour.

http://ruka.org/~toast/atscdata/chart.php?c=7

SHF

Ew, does that mean they are done, over and out? Was enjoying the movies.

What is this Channel 1 you guys speak of?

Thanks again, Paul
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post #11883 of 11909 Old 03-03-2015, 08:36 AM
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Originally Posted by SFischer1 View Post
KFSF went off the air ~ 6 AM it appears.

Check Toast0's chart for outages over a hour.

http://ruka.org/~toast/atscdata/chart.php?c=7

SHF
Ew, does that mean they are done, over and out? Was enjoying the movies.

What is this Channel 1 you guys speak of?

Thanks again, Paul
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post #11884 of 11909 Old 03-03-2015, 12:02 PM
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Quote:
Originally Posted by PaulamI View Post
Ew, does that mean they are done, over and out? Was enjoying the movies.

What is this Channel 1 you guys speak of?

Thanks again, Paul
It's unlikely KFSF is off the air for good. Channel 1 is KAXT, a low power station transmitting from Fremont.

Chuck
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post #11885 of 11909 Old 03-03-2015, 05:50 PM
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Originally Posted by dr1394 View Post
AFD is Active Format Description. This is a method that attempts to display each frame correctly (mostly in an effort to avoid the postage stamp effect).

http://en.wikipedia.org/wiki/Active_Format_Description

Ron
Well, I presume that it would require the decoder to somehow handle the INFORMATION correctly, and now they don't handle basic stuff like the anamorphic flag (I assume it's a "flag") always...

And then there's the guys at the stations who don't seem to know how to set up anything correctly without trying a bunch of times at least. When KRON moved they went through about four iterations of 4-3 until they finally settled on what they wanted, but in doing so they revealed that they are actually a wide-screen channel, so they should have settled on 480i 16:9 anamorphic, but NOOOOO, they pillar-box their content. "Decades" channel 5-2 went through the same nonsense and revealed they too are actually broadcasting 16:9 content pillar-boxed to 4:3 for no good reason other than a certain number of TVs never got the memo about respecting the 16:9 anamorphic flag automatically...ALL channels should broadcast in 16:9 in this year of 2015 in my opinion, even my most brain-dead TV can be set to automatically expand anamorphic screen sizes for all 480i channels, most do it automatically anyway...

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post #11886 of 11909 Old 03-03-2015, 06:50 PM
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Help on Quality feedback

Hi Chuck and Larry and others,

I got some feedback from Al who is able to pick up KFTY-LD Channel 2 from Mt. St. Helena in the mountains near Yosemite. I think this is the furthest I know of anyone regularly watching an LPTV station (he is probably a few more miles away than Chuck, maybe 170 miles total). He says he picks up KFTY-LD 80% of the time, and only picks up KEMO 50 (RF 32) 30% of the time.

He said, only sub-channel 8 looked good on KFTY-LD. I'm running 2.4 Mbps on the .8 channel and the rest have been running 2.05 to 2.1 Mbps. So, I just now turned of the .9 channel on KFTY-LD and bumped up all of the rest of the channels so that everything is running 2.4 Mbps. Does everything look better to you? Granted, my .2 channel and .7 channels come from low quality feeds, but my .4 comes directly from a computer hooked into the mux / encoder, so it should look better as should the other sub-channels.

Perhaps I was too ambitious with 9 sub-channels. If so, then I'll stick with just 8 sub-channels going forward until I can afford a $130,000 encoder from Harmonic that can do 12 sub-channels. The Anywave encoder was about a tenth the price.

I did have problems with my Anywave encoder recentely where the static PSIP info disappeared. I restarted it, but now it looks like the .1 channel is saying .229. I'm asking Anywave for help.

Blessings,
Keith
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post #11887 of 11909 Old 03-03-2015, 07:50 PM
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Keith,

I just compared KFTY DayStar to KACA DayStar which is the only program they show. The color on KACA is over saturated. KFTY looks better in that regard. The video quality looks identical otherwise.

Maybe Al is expecting SD video to look like HD video.

I looked at the transmitter overlay in Google Earth for KFTY and there are a number of good spots on mountaintops west of Yosemite at around 170 miles. Al must be in just the right spot.

The most distant transmitter site that I can receive here is Mt. Toro at 132 miles. KMMD-LD 39 is the most reliable station from there with KION being second.

KFTY is essentially 100% based on signal strength. Occasionally it is affected by local noise and the May through July sporadic-E season gives it trouble at times.

Chuck

Last edited by Calaveras; 03-03-2015 at 07:55 PM.
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post #11888 of 11909 Old 03-03-2015, 08:58 PM
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Quote:
Originally Posted by Calaveras View Post
It's unlikely KFSF is off the air for good. Channel 1 is KAXT, a low power station transmitting from Fremont.

Chuck
KFSF came back on the air ~ 1:40 PM March 3, 2015.


I thought they were going back off again when I saw utilization drop like just before they went off the air. But they are still working.


SHF
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post #11889 of 11909 Old 03-04-2015, 01:47 AM
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I'll have to wait to comment on the quality of K03HY here. Conditions are doing that weird thing again where channel 3's signal is way down at cliff edge levels varying between 14 and 16 dB SNR right now and the picture is breaking up too much to do any quality checking. It normally comes in at 21 to 23 dB, so is about 7 dB weaker than normal.

For the past few days all of the stations that aren't on Sutro or Mt. San Bruno have been varying a lot. KTNC 42 from Mt. Diablo, KTLN 68 from Novato, KRCB 22 from Sonoma, and KEMO 50 from Mt. St. Helena have been holding fairly steady, only varying a few dB, but the Walnut Grove stations and the South Bay stations have been going up and down like yo-yo's as much as 10 dB. They've mostly been at their normal levels or below, and like K03HY, many of them have been floating with the cliff edge. I haven't seen any strong signals for several days now.

One interesting thing I've noticed is how KAXT 1 (RF 42) and KEXT 27 (RF 20) behave so differently from each other. Both are transmitting from Mt. Allison at the same height above average terrrain of 1916 feet, but KAXT is transmitting 15 kW and KEXT is only transmitting 3.6 kW. Neither station comes in here consistently. Sometimes I see one or the other of the two stations, and occasionally I see both at the same time, but not often. You'd think that since the signals are coming from the same place, they'd react the same, so their frequency must be the reason for the differences. I see KAXT 1 more, but when KEXT 27 comes in it's usually stronger, even though it is lower power. KAXT usually peaks at about 19 dB, while I've seen KEXT as high as 21 dB.

I have never seen a picture from the KGO translator transmitting from the same location, nor the KTVU translator from Monument Peak. The signals are there, but they're always below the 15dB cliff edge.

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post #11890 of 11909 Old 03-04-2015, 02:18 AM
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Channel 3's signal is slowly rising and is now varying between 18 and 19 dB, so I've been able to take a look at the picture quality. I see an improvement on all 8 of the sub-channels compared to what I saw when there were 9 sub-channels. There's noticeably less pixelating when they do desolves and fades and the resolution looks better all the way around.

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post #11891 of 11909 Old 03-04-2015, 08:50 PM
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Quote:
Originally Posted by Calaveras View Post
What are you getting?

Chuck
The spectrum analyzer came in todays mail.
I will use this for ganging antennas, stacking, signal shaping, estimating losses in coax cable, and other things.

In a quick set up, KKPX RF 41 is the best station here by a huge margin, at my address, also RF 30 & 29 not far behind.
K03HY the BER shows problems with a fluorescent light ballast on. No BERs with the light off.

Lots of garbage on the unused channels 2,4,5, & 6. Looks like RF 12 bleeds over to RF 11
FM is an overloaded mess.

I am working out the bugs right now, but can do quick simple readings.
The advanced features (such as 6 stations at once) are not set up yet.
This tool is interesting.
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post #11892 of 11909 Old 03-04-2015, 09:11 PM
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VHF Antenna Project

For the last couple weeks I've been building a long log periodic to compare to the two medium sized LPs that I've had on the tower for some time. The originals were 12 elements on a 9.3 foot boom and the long antenna is 22 elements on an 18 foot boom. See first attachment. In theory they should be equal in performance. I ran a bunch of tests on the ground with mixed results. I wasn't sure that tower mounting it would be worth it. I went ahead did it anyway today. Every test always yields some interesting result.

This was a good day to look at signals since there appeared to be no inversion issues. All VHF/UHF stations seemed to have completely nominal signals. The temperature in the valley was about 10 degrees warmer than up here indicating no inversions.

Initial observations show the 22 el to be identical to the pair of 12 elements LPs. Spectrum analyzer traces looked exactly the same, including strengths and waveform shapes. KCBA was 25 dB weaker than KSBW which is the most common difference I've seen over the years. KGO was SNR 20 dB which is exactly the nominal value for no inversions. KNTV was too weak to decode which is normal for no inversions. I compared the 22 el to the small VHF antenna on the other tower. All signal differences tracked exactly.

It's very hard to get much of an idea of the pattern of any antenna because of all the reflections around here. KSBW is the only station strong enough to perform the test and have low enough reflections to get anything meaningful. Attached is the pattern for KSBW. I still think there are some reflections especially in the ENE.

I was hoping that the better F/B ratio predicted for this antenna would translate into a higher SNR for channel 10 which suffers the worst multipath. This did not happen. The SNR was exactly as always. Despite the strong reflections I have, this test is telling me that the multipath is being caused by the vegetation about 1/2 mile away that the Walnut Grove signals have to pass through. There is nothing I can do about that.

Perhaps the only advantage of this antenna over the pair is that there is no fancy combining required and the wind load is probably a little less with no cross mast.

Chuck
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post #11893 of 11909 Old 03-04-2015, 09:18 PM
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Quote:
Originally Posted by 888CALLFCC View Post
The spectrum analyzer came in todays mail.
Very good Ben! It'll take you awhile to figure it all out, especially interpreting what you see means. I'm not surprised to hear there's a bunch of RFI on low VHF. There's a bunch of Part 15 devices out there that don't meet their specs. The FCC has really fallen down on the job.

Swap out that florescent lamp. It should not be causing RFI at 60 MHz.

Chuck
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post #11894 of 11909 Old 03-04-2015, 09:49 PM
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The spectrum analyzer came in todays mail.
Lots of garbage on the unused channels.
What is that ? ... active on 150 through 155 MHz ... below channel 7
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post #11895 of 11909 Old 03-04-2015, 10:54 PM
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What is that ? ... active on 150 through 155 MHz ... below channel 7
Public service stuff is on 148-174 MHz; fire, police, NOAA weather radio, etc.

Chuck
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post #11896 of 11909 Old Yesterday, 01:34 AM
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Quote:
Originally Posted by 888CALLFCC View Post
The spectrum analyzer came in todays mail.
I will use this for ganging antennas, stacking, signal shaping, estimating losses in coax cable, and other things.

This tool is interesting.
Congratulations on your new tool and toy. You're going to have a lot of fun with it!

Larry

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post #11897 of 11909 Old Yesterday, 01:39 AM
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Quote:
Originally Posted by Calaveras View Post
Initial observations show the 22 el to be identical to the pair of 12 elements LPs. Spectrum analyzer traces looked exactly the same, including strengths and waveform shapes.
Chuck
That shows that you build excellent antennas and they do exactly what they're supposed to.

It's going to be interesting to see if the new one reacts the same as the old pair when you start seeing inversions and some weird conditions.

Keep us posted.

Larry

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post #11898 of 11909 Old Yesterday, 06:10 AM
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Quote:
Originally Posted by 888CALLFCC View Post
What is that ? ... active on 150 through 155 MHz ... below channel 7
Some of the really loud signals at 150 MHz are paging systems. I know it sounds super '90s, but pagers are still very much in use by hospital and EMT employees.

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post #11899 of 11909 Old Yesterday, 02:02 PM
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I finally got around to capturing some KPIX bit-stream for analysis. They've definitely upgraded their encoder to something state of the art. I'll guess it's either from Harmonic or Motorola. It's the same encoder that I see used for almost all of the satellite HD channels on Comcast.

Some interesting tricks being used are 3 B-frames and sending a quantiser matrix every frame. AFD is also being sent.

Here's a bit-rate graph. The 5.1 channel is now capped at 15 Mbps.


Ron
Was this change recent, as in the last few weeks? And do you know if a similar change was made with the KBCW encoders? I ask because in the last few weeks I've had audio sync problems with KBCW, audio behind the video, just enough to be noticeable. My feed is via Comcast with a TiVo Roamio but I'm asking here as I'm curious if anyone is seeing this with the OTA feed.

Also, will the new KPIX encoder fix the fast motion blocking that has plagued that channel for years? I'm guessing yes based on the explanation in your following post but I thought I'd ask anyway.

It's certainly possible that Comcast is the cause of both of these problems, especially if it turns out folks are not seeing the problems with the OTA feeds.

Thanks
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post #11900 of 11909 Old Yesterday, 02:09 PM
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I also have a question for the usual OTA crowd.

Do shows such as Agent Carter and Marvel's SHIELD have terrible false-contouring and mosquito-like video noise in the low-lit scenes? It looks awful via Comcast. I transferred and removed all the commercials from a few episodes of Agent Carter and the resulting file size was around 1.75 GBs, which seems really low, even for a 720p channel. The average bitrate was around 5600 kbps. Those numbers just don't seem conducive for a high quality image. Local/live content and commercials(not all but most) all look much better than the network stuff, and it can vary by show, but in general those two shows I mentioned above look terrible. I'm guessing that KGO running two full blown HD channels is not helping matters.

Curious what you folks here have seen.
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post #11901 of 11909 Old Yesterday, 05:23 PM
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Quote:
Originally Posted by Keenan View Post
I also have a question for the usual OTA crowd.

Do shows such as Agent Carter and Marvel's SHIELD have terrible false-contouring and mosquito-like video noise in the low-lit scenes? It looks awful via Comcast. I transferred and removed all the commercials from a few episodes of Agent Carter and the resulting file size was around 1.75 GBs, which seems really low, even for a 720p channel. The average bitrate was around 5600 kbps. Those numbers just don't seem conducive for a high quality image. Local/live content and commercials(not all but most) all look much better than the network stuff, and it can vary by show, but in general those two shows I mentioned above look terrible. I'm guessing that KGO running two full blown HD channels is not helping matters.

Curious what you folks here have seen.
I actually watched much of the last episode of "SHIELD" via broadcast and didn't notice anything like that. I was impressed with at least one scene involving the surround sound channels where a car drove away to the rear in a quite realistic fashion.

Look, everybody knows the cable companies try to rip you off any way they can, the problem is almost certainly not the broadcast station but your cable company dumbing down the video.

Also, I'd like to point out I was REALLY bored to even try to watch "SHIELD" which is a pointless snooze-fest...

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post #11902 of 11909 Old Yesterday, 05:28 PM
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Originally Posted by Keenan View Post
Was this change recent, as in the last few weeks? And do you know if a similar change was made with the KBCW encoders? I ask because in the last few weeks I've had audio sync problems with KBCW, audio behind the video, just enough to be noticeable. My feed is via Comcast with a TiVo Roamio but I'm asking here as I'm curious if anyone is seeing this with the OTA feed.

Also, will the new KPIX encoder fix the fast motion blocking that has plagued that channel for years? I'm guessing yes based on the explanation in your following post but I thought I'd ask anyway.

It's certainly possible that Comcast is the cause of both of these problems, especially if it turns out folks are not seeing the problems with the OTA feeds.

Thanks
I've never noticed any problems like that with the over-the-air broadcasts, this is just another case of the cable company ripping you off.

As far as this new equipment is concerned, I haven't really noticed any difference, it always seemed to me that KPIX or CBS5 or whatever had a slightly "softer" picture than other 1080i stations, but no macroblocking ever that I can recall.

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post #11903 of 11909 Old Yesterday, 05:30 PM
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Quote:
Originally Posted by Calaveras View Post
Public service stuff is on 148-174 MHz; fire, police, NOAA weather radio, etc.

Chuck
Also FM radio is in there, hence the term "FM gap"...

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post #11904 of 11909 Old Yesterday, 05:32 PM
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Quote:
Originally Posted by Keenan View Post
Was this change recent, as in the last few weeks? And do you know if a similar change was made with the KBCW encoders? I ask because in the last few weeks I've had audio sync problems with KBCW, audio behind the video, just enough to be noticeable. My feed is via Comcast with a TiVo Roamio but I'm asking here as I'm curious if anyone is seeing this with the OTA feed.

Also, will the new KPIX encoder fix the fast motion blocking that has plagued that channel for years? I'm guessing yes based on the explanation in your following post but I thought I'd ask anyway.

It's certainly possible that Comcast is the cause of both of these problems, especially if it turns out folks are not seeing the problems with the OTA feeds.

Thanks
The encoder change at KPIX was due to the addition of the new 5.2 sub-channel. I'm not exactly sure when they switched over, I was just waiting for folks to post that 5.2 was active until I made a capture.

I made the capture from the IEEE1394 port of my DCH3200 cable box. I don't have a suitable antenna up for OTA, so I can't capture the original stream. I should rig something up, because I could compare the OTA stream to the Comcast stream and see exactly what Comcast may be doing to the stream.

The new encoder at KPIX is a big step up from their old encoder (the old one wasn't very advanced, even when it was first installed). Although the bit-rate is less, it should look pretty good. Even though MPEG-2 is super mature, top tier encoder manufacturers are still actively tweaking their algorithms.

I'll take a capture of KBCW tonight to see what their using.

Ron

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post #11905 of 11909 Old Yesterday, 05:36 PM
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Quote:
Originally Posted by Keenan View Post
Was this change recent, as in the last few weeks? And do you know if a similar change was made with the KBCW encoders? I ask because in the last few weeks I've had audio sync problems with KBCW, audio behind the video, just enough to be noticeable. My feed is via Comcast with a TiVo Roamio but I'm asking here as I'm curious if anyone is seeing this with the OTA feed.

Thanks
As far as audio lag is concerned, sometimes that just happens because of some lag in handshaking between the receiver and the TV, rarely it happens to me but is very transient and goes away with a new power cycle at the very worst.

Sad thing is you do have to accept that these new-fangled digital systems don't have fully reliable synced-up audio like in the good old analog days...

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post #11906 of 11909 Old Yesterday, 05:41 PM
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Quote:
Originally Posted by Calaveras View Post
Very good Ben! It'll take you awhile to figure it all out, especially interpreting what you see means. I'm not surprised to hear there's a bunch of RFI on low VHF. There's a bunch of Part 15 devices out there that don't meet their specs. The FCC has really fallen down on the job.

Swap out that florescent lamp. It should not be causing RFI at 60 MHz.

Chuck
What do you mean, the FCC has fallen down on the job? When was the last time you saw Janet Jackson's nipple on TV?

If you're talking about maintaining good technical stewardship of the public airwaves, they haven't done that for years. It's all about the money they can grab just like most government agencies in the last few years...

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post #11907 of 11909 Old Yesterday, 05:56 PM
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Originally Posted by dr1394 View Post
The encoder change at KPIX was due to the addition of the new 5.2 sub-channel. I'm not exactly sure when they switched over, I was just waiting for folks to post that 5.2 was active until I made a capture.

I made the capture from the IEEE1394 port of my DCH3200 cable box. I don't have a suitable antenna up for OTA, so I can't capture the original stream. I should rig something up, because I could compare the OTA stream to the Comcast stream and see exactly what Comcast may be doing to the stream.

The new encoder at KPIX is a big step up from their old encoder (the old one wasn't very advanced, even when it was first installed). Although the bit-rate is less, it should look pretty good. Even though MPEG-2 is super mature, top tier encoder manufacturers are still actively tweaking their algorithms.

I'll take a capture of KBCW tonight to see what their using.

Ron
Appreciate the input Ron, and if you could check some OTA streams vs cable that would be really great. In the past Comcast has always claimed that they don't compress(further) the streams they get from the local stations though I'm not sure that's still the case.

I watched that new CSI show last night and it did look quite good. I transferred it from the TiVo and removed the commercials and preview and below is the result. In case you happened to have recorded it yourself.

MediaInfo data,
Spoiler!


Bitrate viewer,
Spoiler!
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post #11908 of 11909 Old Yesterday, 06:20 PM
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Originally Posted by maxreactance View Post
As far as audio lag is concerned, sometimes that just happens because of some lag in handshaking between the receiver and the TV, rarely it happens to me but is very transient and goes away with a new power cycle at the very worst.

Sad thing is you do have to accept that these new-fangled digital systems don't have fully reliable synced-up audio like in the good old analog days...

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It looks like Comcast my be the culprit as I checked the recording I made with a DIRECTV DVR and it appears to be sync'ed correctly. Although, that doesn't preclude something happening at the source as Comcast gets its KBCW/KPIX feed via fiber whereas DIRECTV captures an OTA feed. This was a recording of "The 100".
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post #11909 of 11909 Old Today, 01:12 AM
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Originally Posted by Keenan View Post
I've had audio sync problems with KBCW, audio behind the video, just enough to be noticeable. My feed is via Comcast with a TiVo Roamio but I'm asking here as I'm curious if anyone is seeing this with the OTA feed.
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Quote:
Originally Posted by Keenan
Do shows such as Agent Carter and Marvel's SHIELD have terrible false-contouring and mosquito-like video noise in the low-lit scenes? It looks awful via Comcast.

Thanks
I haven't noticed any audio sync problems OTA on KBCW, but I have on KPIX. During the local news, if they use a feed from KCBS/KCAL in L.A. the audio sync is off and is quite noticeable. Happens every time, so it must be a misadjustment on the LA to SF feed.

KGO looks fine here OTA. I haven't watched any of the ABC programs on Comcast, but will take a look to see if I see a difference.

Larry

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