Channel Detection Scan (channels 2-6)

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NOYB
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Channel Detection Scan (channels 2-6)

Post by NOYB »

Do the OTA tuners such as CONNECT DUAL, DUO & QUTOR etc. still need to scan channels 2-6?
Don't know about the web tool (lineup.json ) but the client utility still scans channels 2-6.
Thought channels 2-6 (VHF low band) were obsoleted.

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jasonl
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Re: Channel Detection Scan (channels 2-6)

Post by jasonl »

Yes, they still need to scan low VHF. There are more low VHF channels now than there were previously (only counting digital channels of course) because stations were given incentives ($$$) to give up their UHF or high VHF channel and move to low VHF as part of the repack.

NOYB
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Re: Channel Detection Scan (channels 2-6)

Post by NOYB »

Really? Why?

The VHF low stations here all went to UHF. One of the three VHF high stations (8) appears to be moving to UHF (23). Currently broadcasting on both. From what I've read the long wave length of VHF low (even VHF high) is a problem for mobile devices because of their small size limiting antenna. And also a problem for indoor antenna's.

jasonl
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Re: Channel Detection Scan (channels 2-6)

Post by jasonl »

Money. WGBH in Boston, otherwise known as the producer of about a third of the shows we think of as "PBS shows", got almost $162 million to move from UHF to low VHF. A ton of viewers in Boston can no longer watch PBS over the air in HD, but $162 million pays for a lot of episodes of This Old House, NOVA, and Frontline, so Boston's loss is our gain.

NedS
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Re: Channel Detection Scan (channels 2-6)

Post by NedS »

Antenna Man had a video about it: https://www.youtube.com/watch?v=FrFib1jaBP0

NOYB
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Re: Channel Detection Scan (channels 2-6)

Post by NOYB »

So that's what the reality is. What was reality supposed to be? It's been a long time since the conversions but I was under the impression, perhaps mistakenly so, that the low band VHF was to be obsoleted.

Glad there are no low band VHF stations here. And only two that are exclusively high band VHF (OBP 10 and and a FOX affiliated independent 12). The two original low band VHF stations, 2 and 6, went to UHF and one of the three original high band stations, 8, now simultaneously broadcasting in UHF band.

Hope the other two high band VHF stations will also move to UHF so they will work better with smaller and indoor antennas.

ebo
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Re: Channel Detection Scan (channels 2-6)

Post by ebo »

On a related note, why does the HDHR scan down from channel 69? Were there ever any digital broadcasts in the US above 51? Soon the upper limit will be 36.

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Re: Channel Detection Scan (channels 2-6)

Post by signcarver »

Many use such at both ends of the spectrum for injection as it is generally easier to properly filter such injection on an end then by a notch as often the notch bleeds (as in lowering strength) into hurting the regular channels as often such filters designed to do so have a slope leading into the neighboring channels the filter was designed to totally block. Also keep in mind that the ATSC model can be used in other countries besides the US.

NOYB
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Re: Channel Detection Scan (channels 2-6)

Post by NOYB »

ebo wrote: Thu Oct 01, 2020 9:09 am On a related note, why does the HDHR scan down from channel 69? Were there ever any digital broadcasts in the US above 51? Soon the upper limit will be 36.
HDHomeRun CONNECT, Model: HDHR4-2US, Firmware: 20200907
Using the web interface (or /lineup.json?scan=start) the scan progresses from channel 14 to 69, 7 to 13, 2 to 6.
Using the hdhomerun_config.exe client utility the scan progresses from channel 69 to 2.
signcarver wrote: Thu Oct 01, 2020 9:19 am Many use such at both ends of the spectrum for injection as it is generally easier to properly filter such injection on an end then by a notch as often the notch bleeds (as in lowering strength) into hurting the regular channels as often such filters designed to do so have a slope leading into the neighboring channels the filter was designed to totally block. Also keep in mind that the ATSC model can be used in other countries besides the US.
My HDHomeRun CONNECT, Model: HDHR4-2US, Firmware: 20200907 setup utility says it's in the "United States". It knows where it is because I told it so. And it's channelmap says "us-bcast". So it knows the details of what to scan for. No reason to scan a bunch of channels if they are not going to exist. Perhaps that day ain't yet. But it's on the horizon.

NOYB
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Re: Channel Detection Scan (channels 2-6)

Post by NOYB »

NOYB wrote: Thu Oct 01, 2020 3:10 pm No reason to scan a bunch of channels if they are not going to exist [don't exist]. Perhaps that day ain't yet. But it's on the horizon.
The repack to move broadcasters from channels 38-51 completion was July 3rd, 2020.
So that day on the horizon I mentioned appears to have already come and gone.

There should be no TV broadcast on channel 37 or above.
Why are we still scanning channels 37 through 69 in the U.S.?
It's bad enough that the VHF (low and high) trash is forced on us.

jasonl
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Re: Channel Detection Scan (channels 2-6)

Post by jasonl »

1. ATSC is used outside the US and some countries still use higher channel numbers. There are a couple dozen stations in Canada that still haven't repacked yet, for example.
2. Some apartment buildings and such will take an antenna feed, filter everything above 51, and then inject other services in that space (security cameras, bulletin board announcements, etc.).

NOYB
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Re: Channel Detection Scan (channels 2-6)

Post by NOYB »

Sounds like there should be a legacy channel map for them to use. Let the rest of us progress.
How many broadcast channels does an apartment building need? They could probably fit at least 10 on a single broadcast channel.

jasonl
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Re: Channel Detection Scan (channels 2-6)

Post by jasonl »

I can't see any reason why SD would even consider it. There's no benefit besides shaving a few seconds off the channel scan (something which normal people rarely if ever do since the device is automatically running background scans and adding new channels on its own anyway) and it potentially breaks working configurations.

I'm not sure how the number of channels they have is relevant. It only takes one. Under your plan the device scans 2-36. Their channel is on 60 and therefore isn't found.

NOYB
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Re: Channel Detection Scan (channels 2-6)

Post by NOYB »

Wondering how much improvement and savings could be made to receivers having to cover less than half the RF spectrum. There is no reason to build UHF Ch. 37 to 69 receivers for U.S. consumer TV equipment. If you think there is why not go all the way and include 70 to 83 too. Oh that's right those have been reallocated too. 1983 called. They want their channels back. How long is SD going to build 52-69, and 37-51 receivers for probably less than 1% of customers that would actually need it (couldn't accomplish the same thing with 2-36)?

It's more than a few seconds. It's about 1/3 the scan time. Which will increase as that spectrum becomes populated with RF signals that has to be analyzed. Not everyone wants built-in background scanning messing up their TV channel line up. There are other ways of automating scans too. And the less time spent scanning is the less likely to impact a recording.

My SD device has a location option for Canada. See no reason the U.S. location should need to accommodate the Canada channels.

Apartment building that needs more than a RF channel or two should probably be using commercial equipment instead of consumer. Those that don't can use one of the supported RF channels 2-36. Maybe an opportunity to sale more commercial equipment.

Don't have to break anything.
U.S. map stays the same.
"Modern" Option restricts to ch. 2 - 36. Only applied by user action for existing installations.
Or could even auto apply it to tuners that don't have any channels above 36.

Start the weaning.

NedS
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Re: Channel Detection Scan (channels 2-6)

Post by NedS »

No offense, but this is like watching someone make the most impassioned plea for racing stripes to be printed on the case.

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