dancytron
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Re: New TV Tuner from HQ

Tue Oct 23, 2018 10:22 pm

ab1jx wrote:
Tue Oct 23, 2018 8:31 pm
Is there any more technical information available? Does it work outside the UK? Here in the US we have DVB-T, we don't use PAL video (we have NTSC), our standard TV antenna connector is the "F-connector" https://en.wikipedia.org/wiki/F_connector Looks like the chrome connector is an adapter that plugs into the board, we'd probably want a different one. Is that a CRC connector on the board itself? There are a few similar ones, I have something similar on my RTL2832 SDR/DVB dongles, a slightly different (incompatible) one on a Huawei cell modem. I can buy a Chinese TV and it works.

This will be my first "hat", looks like it should fit fine on my Pi with the official touchscreen display, wonder how that will work out. I do have a couple of bluetooth keyboards, one a small handheld one. Wonder if there's a way to make controls appear on the touchscreen while something's on the TV? I don't watch much really except Star Trek reruns. Can't get Dr Who.

Kodi looks like a newer generation of MythTV, used to use that with a Happauge card that plugs into a PCI slot. I took a quick look for a way to make Kodi work with my RTL2832 in DVB mode but didn't see one.

The page at https://www.raspberrypi.org/products/ra ... -now-modal says there are no resellers in my region. Wonder if that's a permanent thing? I was all set to order one too.
The U.S. does not have DVB-T. The U.S. has ATSC, which is different. This new Pi hat will not work with U.S. broadcast TV.

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ab1jx
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Re: New TV Tuner from HQ

Tue Oct 23, 2018 10:50 pm

dancytron wrote:
Tue Oct 23, 2018 10:22 pm
The U.S. does not have DVB-T. The U.S. has ATSC, which is different. This new Pi hat will not work with U.S. broadcast TV.
Bummer, yeah, that's right ATSC (digital) replaced NTSC (analog). Most of the world has DVB-T (I guess) which replaced PAL. I think the differences are minor so most things I see do both, probably with the same chip. https://en.wikipedia.org/wiki/Digital_V ... oadcasting

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Mettauk
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Re: New TV Tuner from HQ

Tue Oct 23, 2018 10:58 pm

DarkPlatinum wrote:
Fri Oct 19, 2018 6:58 pm
How much beter is this from this since they are similarly priced ?https://shop.pimoroni.com/products/mini ... l-tv-stick
Well its T2 for a start - It can pick up HD broadcasts, if you can get it working that is! :?
As humans we have been the same for a very very long time, technology changes how we do... not who we are as people.

noggin
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Re: New TV Tuner from HQ

Tue Oct 23, 2018 11:51 pm

ab1jx wrote:
Tue Oct 23, 2018 10:50 pm
dancytron wrote:
Tue Oct 23, 2018 10:22 pm
The U.S. does not have DVB-T. The U.S. has ATSC, which is different. This new Pi hat will not work with U.S. broadcast TV.
Bummer, yeah, that's right ATSC (digital) replaced NTSC (analog). Most of the world has DVB-T (I guess) which replaced PAL. I think the differences are minor so most things I see do both, probably with the same chip. https://en.wikipedia.org/wiki/Digital_V ... oadcasting
Not quite. There's no like-for-like mapping from old to new standards - you can't say NTSC was replaced by ATSC, nor PAL by DVB-T universally.

ATSC replaced NTSC in the USA, Canada, South Korea and Mexico. ISDB-T has replaced NTSC in Japan. Taiwan replaced NTSC with DVB-T.

Europe - which was both PAL and SECAM - has switched to DVB-T and/or DVB-T2. Australia, New Zealand and India have gone DVB-T from PAL too. China has gone from PAL to their own DTMB standard.

Africa was a mix of PAL and SECAM and has largely migrated to DVB-T/T2, though there are pockets of DTMB and ISDB-T.

South America has largely switched from their various forms of PAL to ISDB-T (Brazil used PAL-M system which was a PAL system with the same 525/60 line rate and frame rate as NTSC, others used PAL-N which was European 625/50 but with a lower colour subcarrier frequency to work in 6MHz channels), with a few European-influenced areas switching to DVB-T.

DVB-T/T2, DTMB and ISDB-T are all COFDM standards (which use thousands of carriers), ATSC is the odd one-out in using 8VSB on a single carrier. ATSC 3.0 uses a more DVB-T2 like solution.

Also - it's worth remembering that DVB-T doesn't mean SD and DVB-T2 doesn't mean HD. Both standards are used to carry both flavours somewhere around the world. (Norway, Ireland and Australia for example use DVB-T for HD - Norway and Ireland use H264, Australia initially used MPEG2. The UK uses H.264 on DVB-T2 for both SD and HD services, and uses MPEG2 on DVB-T for SD services. Germany now uses H265/HEVC on DVB-T2, and is the first region to use 1080p properly for broadcast - as they are 1080p50 not 1080i25 for their Full HD services, with SD services carried in 540p50, not 576i25. They have axed interlace entirely from their platform AIUI)
Last edited by noggin on Wed Oct 24, 2018 7:36 am, edited 1 time in total.

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ab1jx
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Re: New TV Tuner from HQ

Wed Oct 24, 2018 12:08 am

That one at Pimoroni looks like this one at Nooelec: http://www.nooelec.com/store/sdr/sdr-re ... r820t.html I have 3 of them for SDR. I read somewhere that even if you can get the driver working they can't pump data through the USB fast enough so you end up with black and white TV. And the DVB driver conflicts with the SDR driver so you usually have to blacklist the DVB driver to keep it from loading.

That's why I was glad to see this with a faster interface. The one used for SDR also only has an 8 bit A/D which is mostly enough.

--------

Oh well, it's only television. Maybe the creators of the tvhat got a look at American TV and decided it wasn''t worth bothering with. And they're probably right. I mostly quit watching it in 2012. It's 1/3 advertising, with plots that a 10 year old could have written. And almost no science fiction anymore except reruns. Politically, the religious far-right maintains TV in a death grip and heavily censors movies. Online news is better and faster, I have a BBC app on a phone which I check for new stories several times a day. There's also ad-blocking for the internet. TV's mostly a way to waste time for children and the elderly. Get hooked on programming (computers) and you won't have patience for television.

noggin
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Re: New TV Tuner from HQ

Wed Oct 24, 2018 10:12 pm

My Pi TV uHAT has arrived. Installed it on a spare 3B+.

With a download of the latest Raspbian, installed TV Headend using apt-get. All set-up fine with our rooftop aerial pointed at Crystal Palace. Using cabled ethernet to the Pi.

Tuning to BBC One HD on PSB 3 (aka BBC B) in VLC on my Mac. Simultaneously I was also able to stream BBC Two HD in Kodi on my Mac (Mac is also connected via a cabled Ethernet connection), and ITV HD from a TV Headend client on my iPhone (via WiFi)

No obvious break-up or corruption - so it appears that the TV uHAT has no issues streaming multiple services from the same mux simultaneously. Will try and get all 5 HD channels streaming simultaneously tomorrow to stress test the set-up.

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Mettauk
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Re: New TV Tuner from HQ

Wed Oct 24, 2018 10:50 pm

Can anyone tell me what the two pads on the top of the board are for?
As humans we have been the same for a very very long time, technology changes how we do... not who we are as people.

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ab1jx
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Re: New TV Tuner from HQ

Thu Oct 25, 2018 1:01 am

Mettauk wrote:
Wed Oct 24, 2018 10:50 pm
Can anyone tell me what the two pads on the top of the board are for?
It would be nice to find a place to feed in composite video, hee hee. No idea. Looking up the datasheet on that biggest chip might give a clue.

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ab1jx
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Re: New TV Tuner from HQ

Thu Oct 25, 2018 1:35 am

Useful chart at Wikipedia, maybe a little off-topic. https://upload.wikimedia.org/wikipedia/ ... dards8.svg
Image Interesting that they're arranged so (of course) aspect ratios are diagonal lines. I was looking up 1080p and found it. https://en.wikipedia.org/wiki/1080p

gordon77
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Re: New TV Tuner from HQ

Thu Oct 25, 2018 9:18 am

gordon77 wrote:
Tue Oct 23, 2018 6:45 pm
Cheers, l missed that. :D
Success at last !

I tried the instructions given for the hat but very jerky pictures on a PC, via browser. So followed Dougies instructions ( viewtopic.php?f=35&t=225036#p1381937) for installation. Then connected PC and followed the instructions to let tvheadend find channels but found nothing.
We watch a TV relay so its not in the list of main TV sites, so found a main station with the same channels as our relay and success it found the 3 muxes. For UK see http://static.ofcom.org.uk/static/recep ... x.asp.html if required. I suppose there is a manual method to add them to tvheadend but I didn't find it.

Then ran Kodi and the Pi now works as standalone HDTV receiver plugged into my TV :D
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noggin
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Re: New TV Tuner from HQ

Thu Oct 25, 2018 11:34 am

*** EDIT - updated with some missing steps and additional information - including how to get Kodi to use Freeview channel numbers :) ***
gordon77 wrote:
Thu Oct 25, 2018 9:18 am
gordon77 wrote:
Tue Oct 23, 2018 6:45 pm
Cheers, l missed that. :D
Success at last !

I tried the instructions given for the hat but very jerky pictures on a PC, via browser. So followed Dougies instructions ( viewtopic.php?f=35&t=225036#p1381937) for installation. Then connected PC and followed the instructions to let tvheadend find channels but found nothing.
We watch a TV relay so its not in the list of main TV sites, so found a main station with the same channels as our relay and success it found the 3 muxes. For UK see http://static.ofcom.org.uk/static/recep ... x.asp.html if required. I suppose there is a manual method to add them to tvheadend but I didn't find it.

Then ran Kodi and the Pi now works as standalone HDTV receiver plugged into my TV :D
You can manually add muxes in TV Headend if you don't use the wizard.

It has a number of steps.

You first go to the TV Headend web page then go to the CONFIGURATION TAB, then the DVB INPUTS tab. You should see the Sony adaptor on the TV Hat in the Adaptors list.

First you create a Network in the NETWORKS tab (this is nothing to do with Ethernet and is instead creating a TV Network entry). Click Add, Select DVB-T Network and give your Network a name. You may find you get a lot of additional options if you have Expert view enabled. You can usually safely leave these on defaults.

Once you've created a network you can add that network to your DVB-T/T2 adaptor. Go to the TV Adaptors tag, select the DVB-T Tuner for the Sony adaptor, Click on the adaptors drop down in the panel on the right hand side for that adaptor, and select the new network you named above. You should also enable the adaptor by ticking in the enabled box, and click SAVE at the bottom of that panel.

This has now told TV Headend that the DVB-T Network you created can use the TV uHAT tuner.

You now need to add some muxes (these are the individual frequencies used for broadcasting DVB-T/T2 channels). Click on the MUXES tab, Click ADD, you will then be asked which Network your mux is in, so select the network you named earlier (this will probably be the only entry in the drop down)

You can then add the frequency - it needs to be in Hz not MHz kHz - so for PSB1 on Crystal Palace (BBC SD channels) you'd enter 490000000 (for 490MHz / C23). You'd leave the Delivery System as DVB-T, you'd select 8MHz Bandwidth, QAM/64 Constellation, 8k Transmission Mode and leave the rest on Auto (You may find you can leave more on Auto - but every DVB-T/T2 adaptor I've used works with those as the minimum) You can then click Create (if you just want to enter one mux, or Apply if you want to keep the box open to add more)

To find out the frequencies of your transmissions UK Free TV can be quite useful - though COM7 and COM8 (the lower power DVB-T2 muxes that carry things like BBC News HD, BBC Four HD/CBeebies HD) have recently begun to move to C55/746MHz and C56/754MHz nationally as Single Frequency Networks and this may not have updated.

For UK DVB-T muxes you need : DVB-T, 8MHz, 64/QAM, 8k as your settings
For UK DVB-T2 muxhes you need : DVB-T2, 8MHz, 256/QAM, 32K as your settings

TV Headend should automatically scan once you save each mux, but if not a reboot often helps, or you can select your network in the Networks tab and click 'Force Scan'

You may find that if Network Autodiscovery is enabled that if you just enter PSB1's details, once TV Headend tunes that mux, all the other SD muxes in your area will appear in your mux list and then automatically be scanned. You will probably need to manually enter PSB3, COM7 and COM8 though.

When all of your muxes have been found, you will see all the TV, Radio and possibly other services that TV Headend has found in the SERVICES tab, next to the MUXES tab. In the services tab you need to Map those services - using MAP ALL SERVICES (usually). This will map your services to TV Headend channels and channel names. It will also map them in TV Headend to the Freeview / Freeview HD LCNs (Logical Channel Numbers) - so BBC One is on 1, BBC One HD is on 101 etc.

HOWEVER by default Kodi's Live TV functionality ignores back-end channel numbers, however you can enable this in Kodi via the System->PVR & Live TV settings option of 'Use Channel Numbers from Backend'

Other things you can do :

If you want a Freeview HD EPG (Freeview SD has an Open EPG, but Freeview HD's EPG is compressed using a different system) then you will need to enable the Freeview HD EPG grabber in the EPG configuration tabs. If you just use the DVB EIT grabber you may find DVB-T2 channels have gibberish for their programme details.

If you want PDC-style accurate recording, I think you'll need to check 'Use EPG Running State' in the Recording Tab (UK DVB-T/T2 mainstream broadcasters accurately send 'Programme Start/End' using the EIT Present/Following entries to allow you to control recording via these rather than just a timer. Other regions may not be so good at this) This entry uses these to make sure recordings are accurately made.
Last edited by noggin on Thu Oct 25, 2018 4:49 pm, edited 1 time in total.

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bensimmo
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Re: New TV Tuner from HQ

Thu Oct 25, 2018 12:07 pm

That's a very useful post,most detailed with EPG info I've seen.
It might make it actually nice to use for Freeview.
I have other setup I just gave up with as auto channel numbering and EPG setup just never worked.
So I kept on with WMC until it just couldn't cope (with various Win10 updates).


It's a shame Freeview/FreeviewPlay don't sell a reasonable priced program to use, given most the TVs /boxes run Linux or Android in the background anyway.

gordon77
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Re: New TV Tuner from HQ

Thu Oct 25, 2018 12:30 pm

Thanks noggin for the details, very useful. Getting 'auto' to work appears a lot simpler :)

noggin
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Re: New TV Tuner from HQ

Thu Oct 25, 2018 4:22 pm

bensimmo wrote:
Thu Oct 25, 2018 12:07 pm
It's a shame Freeview/FreeviewPlay don't sell a reasonable priced program to use, given most the TVs /boxes run Linux or Android in the background anyway.
I'm afraid that's not likely to happen. Freeview HD licensing mandates the ability to use DTCP copy protection DRM on all recordings made of Freeview HD content. That restricts playback of material to the device the material was originally recorded on. I don't see this really being a popular application...

noggin
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Re: New TV Tuner from HQ

Thu Oct 25, 2018 4:28 pm

Just installed my TV uHAT on a Pi Zero (which is using a Google Chromecast combined PSU+Ethernet adaptor to provide power and cabled network connectivity)

Even running a Pixel desktop (I used the same uSD card I used for testing on a 3B+) the Zero was able to stream 3 Freeview HD streams (BBC One HD, BBC Two HD and ITV HD to three separate clients with no obvious frame drops or corruption)

'top', via SSH, reported c.30-40% CPU utilisation when doing so.

I've seen a tweet reply from Gordon Hollingworth confirming that the DVB-T/T2 interface over the SPI bus can run at 100Mbs - so is more than capable of carrying a full 40.25Mbs transport stream from the highest capacity DVB-T2 muxes we have in the UK.

Of course my current solution would only be able to record to uSD card - as the single USB port is taken up with the Chromecast PSU+Ethernet adaptor, but if you used a PSU and an OTG Ethernet+USB hub combo (which are widely available - I can't find mine at the moment!) you could use an external USB storage device I guess. This may push the Zero quite hard but as a Live TV solution it's really neat!

Next I'll try LIbreElec on it to see how good/bad it really is doing both backend and frontend duties (not recommended by the foundation)

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ab1jx
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Re: New TV Tuner from HQ

Thu Oct 25, 2018 5:06 pm

bensimmo wrote:
Thu Oct 25, 2018 12:07 pm
It's a shame Freeview/FreeviewPlay don't sell a reasonable priced program to use, given most the TVs /boxes run Linux or Android in the background anyway.
MythTV at least used to scan EPGs on all the channels and put them into a database (MySQL I think) then make that into a web page on demand. Shows were clickable, a double-click would change channels and bring it up. Not sure about Kodi.

There's also http://www.schedulesdirect.org/ which you subscribe to for $25/year. You can try it a week for free, and/or get shorter than a year as subscription. You download new listings once a week or so. They're very picky about only using their service with open-source software, and it is a non-profit. Coverage regions are listed at http://www.schedulesdirect.org/regions and they at least try to be world-wide. They're approachable about adding channels in your area they might be missing. Approved software is listed at http://www.schedulesdirect.org/approvedsoftware you'll probably find some in the Raspbian debs. I used to use MyTelly from the UK.

noggin
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Re: New TV Tuner from HQ

Thu Oct 25, 2018 5:31 pm

ab1jx wrote:
Thu Oct 25, 2018 5:06 pm
bensimmo wrote:
Thu Oct 25, 2018 12:07 pm
It's a shame Freeview/FreeviewPlay don't sell a reasonable priced program to use, given most the TVs /boxes run Linux or Android in the background anyway.
MythTV at least used to scan EPGs on all the channels and put them into a database (MySQL I think) then make that into a web page on demand. Shows were clickable, a double-click would change channels and bring it up. Not sure about Kodi.

There's also http://www.schedulesdirect.org/ which you subscribe to for $25/year. You can try it a week for free, and/or get shorter than a year as subscription. You download new listings once a week or so. They're very picky about only using their service with open-source software, and it is a non-profit. Coverage regions are listed at http://www.schedulesdirect.org/regions and they at least try to be world-wide. They're approachable about adding channels in your area they might be missing. Approved software is listed at http://www.schedulesdirect.org/approvedsoftware you'll probably find some in the Raspbian debs. I used to use MyTelly from the UK.
In the UK TV Headend has full Freeview HD EPG - and the platform provides a 7 day EPG for all services, on all services (there is pan-UK co-operationbetween networks to ensure consistent EPG delivery for all services whatever channel you are watching)

Freeview HD+ means that we also have very good PVR functionality - and the big broadcasters (BBC, ITV, C4, C5 etc.) properly trigger EIT P/F (Present Following) to allow for second accurate recording triggers, allowing PVRs to neatly record shows even if their on-air and off-air times are not quite as billed. (The recording usually includes the programme introduction ident - so any content warnings are also recorded, and will usually record the following item as well so any post-show follow-ups for Action Lines etc are also recorded)

The technical issue in the UK is that the Freeview HD (and Freesat for that matter) EPGs are compressed using proprietary, licensed, Huffman tables. These tables have been reverse engineered and thus TV Headend (and some other PVR back-ends - though for a long time VDR didn't) include these tables and thus can provide a full Freeview HD EPG (Freeview SD uses standard DVB EIT EPG functionality so 'just works') I suspect Freeview HD aren't amazingly happy that their tables are being distributed in open source products - but I suspect a commercial product using them 'unlicensed' would be treated diffferently.

The only real reason to pay for schedule data in the UK is if you want additional metadata - as some listings providers will provide richer metadata than the standard Freeview / Freeview HD EPG. (Though I think TV Headend now also includes some metadata scraping support?)

You can schedule recordings from within Kodi (it has a nice graphical multi-channel grid or single channel listings) or you can use the TV Headend web interface, which includes some nice search functionality.

Both routes will let you set 'Series Links'. I don't know if these use the Freeview+ series link metadata though.

wolf.z
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Re: New TV Tuner from HQ

Thu Oct 25, 2018 9:34 pm

ab1jx wrote:
Tue Oct 23, 2018 10:50 pm
...
Bummer, yeah, that's right ATSC...Most of the world has DVB-T (I guess) ... I think the differences are minor so most things I see do both, probably with the same chip. ..
No. DVB uses the very latest in modulation, OFDM, versus ATSC using 8VSB. The RTL2832U does demodulate that OFDM in hardware. Likely, the sony will act similar, but I can't judge since I found no datasheet source. Demodulating such advanced schemes is a complex task, that's why specialized hardware is existing, as is with ATSC or DVB.
However, things have changed, and new chips arrived, enabled to do many out of DVB, ATSC, and ISDB. With one, claiming to do all: https://saankhyalabs.com/sl-300/

Back to the Pi Hat.
I suspect, the foundation choose Sony having UK based Fab rather than other suppliers elsewhere.
I wonder, how good the hardware developers handled the noise issue with the hat being such close to the "noisy" Pi itself in comparison to USB dongles.
Mechanically, a hat integrates far better than a dongle, not meant to be fixed somewhere other than the USB plug.

I would be glad to hear from someone, doing a 1:1 comparison of RTL2832&R820T and CXD2880 in means of reception quality/margin.

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ab1jx
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Re: New TV Tuner from HQ

Fri Oct 26, 2018 12:26 am

Hmm, I was a licensed TV repairman back in the analog world of the 1970s. But I spent 10 years in consumer electronics and got out of it long before digital TV came along. I'm also an extra class ham so I look at big wide messes of RF like digital TV and cell phone in an SDR program like HDSDR or gqrc or sdrsharp and it seems incomprehensible. And I have other things to do. I haven't tried different demodulation schemes, I've heard Gnuradio does some.

I would think the Pi Hat being 10 years newer than the RTL2832&R820T would make it better. Noise I suspect would only be an issue in weak signal areas. The closeness to the CPU has to have speed benefits, some RTL2832&R820T sellers recommend a short USB extension cord to put a little distance between them. People use them for radio astronomy, that's a lot different than getting a local TV station belching megawatts. Odds are most people have strong signals.

I was interested in using one on a Pi with touchscreen then using that as normal computer the rest of the time. I thought DVB-T meant Digital Video Broadcasting-Terrestrial generically and might include ATSC. Seems like they could make different hats for different areas, not sure it would be profitable. Just different boards with different chips. I could even use something with composite video in since I still have a couple ATSC set-top boxes, but that would require digitizing. The price is good.

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bensimmo
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Re: New TV Tuner from HQ

Fri Oct 26, 2018 7:01 am

The price is good for a T2 device.

There are older Sony DVB chipset info people can have a look at, how similar they are I have no idea.
Just do a general search on sony CXD2 and CXD28 etc.

I hope they have a 'how we did it' blog post at some point. Though I think, unless I missed it, the how we fixed the PoE HAT post.

noggin
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Re: New TV Tuner from HQ

Fri Oct 26, 2018 8:46 am

ab1jx wrote:
Fri Oct 26, 2018 12:26 am
I thought DVB-T meant Digital Video Broadcasting-Terrestrial generically and might include ATSC.
Unfortunately, that's not the case. DVB is a family of digital TV standards developed, initially, in Europe but used globally. It defines terrestrial (DVB-T/T2), satellite (DVB-S/S2) and cable (DVB-C and the unused DVB-C2) standards.

DVB-T arrived c.1998, at around the same time as the US ATSC 8VSB system, but uses COFDM. Cox stations in the US advocated DVB-T for the US, due to its better performance with multipath, but ATSC prevailed. Canada and Mexico followed suit with ATSC, and South Korea migrated to it too. Europe, Aus/NZ, and large parts of Asia went DVB-T.

DVB-S was the satellite variant - and was used across the world (including the US for FTA services and broadcast and news contributions), and DVB-C is the cable variant (the US went with an ATSC QAM variant for cable)

There are now second generation, more efficient, DVB-T2 and DVB-S2 services (largely rolled out for high definition roll out) which massively increase the bitrate you can broadcast in a given RF channel. DVB-C2 was also developed - but wasn't adopted as DVB-C was 'good enough'

DVB-T2 in the UK allows us to carry 40.25Mbs in a standard UK 8MHz channel - and as a result our 5 main networks (BBC One, BBC Two, ITV, C4 and C5) can all be carried in a single RF channel using H264 compression with some optimised encoding.

The big advantage of DVB is that the three standard families - T/T2, S/S2 and C - are designed to interoperate - which makes running across the platforms pretty neat.
Last edited by noggin on Fri Oct 26, 2018 8:57 am, edited 1 time in total.

noggin
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Re: New TV Tuner from HQ

Fri Oct 26, 2018 8:50 am

bensimmo wrote:
Fri Oct 26, 2018 7:01 am
The price is good for a T2 device.

There are older Sony DVB chipset info people can have a look at, how similar they are I have no idea.
Just do a general search on sony CXD2 and CXD28 etc.

I hope they have a 'how we did it' blog post at some point. Though I think, unless I missed it, the how we fixed the PoE HAT post.
If you look at Linux mailing lists you'll see lots of CXD2880 SPI driver contributions from people with Sony e-mail addresses dating back to at least April last year, specifically mentioning testing on the Raspberry Pi 3!

I've not seen any references to this chip elsewhere, and the fact it uses SPI, rather than USB or an MPEG2 parallel or serial TS interface is interesting. I wonder if the Raspberry Pi team and Sony worked to develop a low cost SPI-based chip for SBCs - or the Pi specifically.

I also wonder if Sony have also included DVB-C functionality in it (but not exposed it yet) as their other main DVB tuner used in USB sticks, the CXD2820R, is DVB-T/T2/C.
Last edited by noggin on Fri Oct 26, 2018 12:06 pm, edited 1 time in total.

fruitoftheloom
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Re: New TV Tuner from HQ

Fri Oct 26, 2018 9:07 am

RPT worked with Cypress for the RPi 3B+ WiFi / BT Chip and Microchip for the USB (Ethernet PoE) Chipset, so it would perfectly reasonable to assume that they approached Sony who undertake manufacturing in both Wales and Japan of Raspberry Pi SBCs...
adieu

Asus CS10 Chromebit / HP Envy 4500 Wireless Printer / Raspberry Pi Model 2B v1.1 / RealVNC Software...

noggin
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Re: New TV Tuner from HQ

Fri Oct 26, 2018 12:09 pm

fruitoftheloom wrote:
Fri Oct 26, 2018 9:07 am
RPT worked with Cypress for the RPi 3B+ WiFi / BT Chip and Microchip for the USB (Ethernet PoE) Chipset, so it would perfectly reasonable to assume that they approached Sony who undertake manufacturing in both Wales and Japan of Raspberry Pi SBCs...
Yes - that would make total sense, and shifting DVB-T/T2 duties away from the USB bus also makes a lot of sense in reducing USB bandwidth terms. Previously if you used a Pi for DVB-T/T2 streaming and PVR duties you could have the same data going over the bus three times - once from the USB tuner to the Pi, and then twice if it was both being streamed over Ethernet and recorded to USB attached storage (as the Ethernet port hangs off the same, single, USB 2.0 bus as the 4 USB ports)

It's the same reason the on-board WIFi makes sense I guess - as that removes that function from the USB bus compared to using a WiFi dongle.

scotty101
Posts: 3648
Joined: Fri Jun 08, 2012 6:03 pm

Re: New TV Tuner from HQ

Fri Oct 26, 2018 12:37 pm

wolf.z wrote:
Thu Oct 25, 2018 9:34 pm
I wonder, how good the hardware developers handled the noise issue with the hat being such close to the "noisy" Pi itself in comparison to USB dongles.
If you look at the PCB almost the whole back side of it is a ground plane and there are huge number of vias between the layers of the PCB.
Electronic and Computer Engineer
Pi Interests: Home Automation, IOT, Python and Tkinter

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