Channel Detection Scan (channels 2-6)

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NOYB
Posts: 161
Joined: Thu Dec 12, 2013 2:12 am

Re: Channel Detection Scan (channels 2-6)

Post by NOYB »

ebo wrote: Tue Oct 06, 2020 10:20 am The answer that should satisfy everyone is to make the scanning range a user option. 2-51 or even 2-69 could be the default but let the users who are annoyed by the time it takes change the range to 2-36 or 8-23 or whatever is best for them.
Yup. It is extremely unlikely that my device will ever need to scan anything outside the official allocated TV channel range of 2-36. Probably more likely that I could jump over the moon. Probably similar for the vast majority of units in the U.S. and Mexico. And soon to be Canada. I was actually surprised that Mexico seems to been further along then Canada with regard to TV frequency spectrum allocation being channels 2-36. Not sure about conversion to digital, but every channel I did pull up details on was digital. So maybe they are with that too.

If Canada would get with it and stop lagging behind all North America could be channels 2-36 digital. Instead of dragging this piecemeal nonsense out as long a possible. Maybe manufactures needed some place to dump their U.S and Mexico incompatible TV's.

Choices. I like choices.

kyl416
Posts: 8
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Device ID: 1080DB11
Location: Tobyhanna, PA
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Re: Channel Detection Scan (channels 2-6)

Post by kyl416 »

The repack phases only applied to Full Power and Class A stations. There are still numerous licensed LPTV stations and translators in the 38-51 range in the USA, these can be anything from so-called "useless" channels like shopping/religious, to very popular diginets like Cozi that for various reasons couldn't get clearance on a full power station in a given market, and for people in an area served by a translator, it could be their only way of picking up a big 5 network over the air. (i.e. Ukiah California where translators for the major San Francisco stations are currently in the 38-51 range) Because of the limited availability of tower crews and equipment, LPTV and Translators were not included as part of the repack phases, the majority of them now have construction permits for new frequencies in the 2-36 range, but many don't expire until 2022-2023, and depending on how bad the crew backlog still is by then, those expirations can be extended. Some of them are still analog too since the digital transition was only required for Full Power stations, but their new post-repack facilities in RF 2-36 will be digital.

As for 2-6, it was known back in 1998 that 2-6 would NOT be eliminated in the 2009 DTV conversion:
The Commission adopted a core spectrum of channels 2-51 for DTV. This decision will eliminate industry uncertainty about the status of VHF channels 2-6
Major makets like Philly have had full power VHF-lo digitals since 2009, and there were even more across the country once you start including Class A/LPTV/Translators. And it only became more populated since then, especially post-repack.

RabbitEars keeps stats of the allocated digital channels in the USA, here are the pages for the individual channel numbers so you can see a combined list of Full Power and LPTV stations:
RF 2
RF 3
RF 4
RF 5
RF 6
RF 38
RF 39
RF 40
RF 41
RF 42
RF 43
RF 44
RF 45
RF 46
RF 47
RF 48
RF 49
RF 50
RF 51

Also I just looked up your DMA Portland, it has a LPTV station KPWC-LD that will return to air on RF 6 after it was displaced from RF 24 by KATU, and there's a currently silent repeater of KRCW that's licensed for RF 5. While you may personally be out of range of these LPTV signals, they still count as part of your DMA.

wb6lzv
Posts: 4
Joined: Sun Oct 18, 2020 7:16 am

Re: Channel Detection Scan (channels 2-6)

Post by wb6lzv »

I too would support having the channel scan limits be user-defined with the default being ALL. I have 2 HDHomeRuns (HDHR-US and HDHR5-4US). The HDHR5-4US is connected to a Plex Media Server and I continuously scan the tuner ports on the HDHR-US and upload the results to the RabbitEars Live Bandscan server. Scanning channels above 36 and processing the results to RabbitEars adds another minute or so that could otherwise be used to look for signals of interest (e.g. DX). It's not a huge deal, and would be a more of a "nice to have". I know my usage is in the minority. Here are my live bandscans. I have different antennas connected to the tuner ports on the HDHR-US.

https://m.rabbitears.info/index.php?req ... it=&auto=Y

https://m.rabbitears.info/index.php?req ... it=&auto=Y

tmm1
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Re: Channel Detection Scan (channels 2-6)

Post by tmm1 »

If you're using hdhomerun_config then you can simply modify the frequency ranges to suit your needs: https://github.com/Silicondust/libhdhom ... nels.c#L93

wb6lzv
Posts: 4
Joined: Sun Oct 18, 2020 7:16 am

Re: Channel Detection Scan (channels 2-6)

Post by wb6lzv »

Yes... I am calling hdhomerun_config from a Python script on a Linux box. Thanks for the tip. I didn't create the original script and I'm not proficient in Python... so I'll need to digest this a little more to effectively incorporate it.

Cheers!
Craig

wb6lzv
Posts: 4
Joined: Sun Oct 18, 2020 7:16 am

Re: Channel Detection Scan (channels 2-6)

Post by wb6lzv »

Let me see if I get this right. All I should need to do is re-compile hdhomerun_config for my OS with the following changes to the hdhomerun_channels.c file:

/* US antenna channels. */
static const struct hdhomerun_channelmap_range_t hdhomerun_channelmap_range_us_bcast[] = {
{ 2, 4, 57000000, 6000000},
{ 5, 6, 79000000, 6000000},
{ 7, 13, 177000000, 6000000},
{ 14, 36, 473000000, 6000000},
{ 0, 0, 0, 0}
};

In this case nothing will change with my Python script, except the channel scans will stop at 36?

wb6lzv
Posts: 4
Joined: Sun Oct 18, 2020 7:16 am

Re: Channel Detection Scan (channels 2-6)

Post by wb6lzv »

Well... I answered my own question! It works perfectly, and it was so simple! Again, thank you tmm1 for the tip.

Cheers,
Craig

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