I don't know. What @tmm1 stated made it sound like the single tuner could split itself into subtuners without using any of the other 3 tuners. Which is exciting at first. But, somehow, I think they would have made it more clear and advertised the device as supporting 10 simultaneous channels if this was the case (it wouldn't be a Quatro anymore, it would be a HDHR Deco). I think it is still limited to the 4 tuners on the device, able to tune 4 channels. But all 4 can be from a single frequency ATSC3 stream, as long as 2 of the subchannels are 8VSB.
Sweet. Love it that you guys are already looking at this.
I believe this will technically be possible, but only when tuning for the physical channel and not filtering the stream. Unfortunately, this is not presently how Channels handles tuning devices that can accept the HTTP API (HDHR4 and newer).
As an example, say that you receive your NBC and its subchannels on 4.1, 4.2, and 4.3, and they are broadcast on UHF channel 32. The way Channels currently works is that each virtual channel is separately requested, and consumes a separate tuner. So, when you want 4.1, Channels asks the tuner for it, the tuner tunes physical channel 32, filters out all of the other subchannels, and delivers only 4.1. If you want to tune 4.3 on a different client concurrently, Channels makes a second request for 4.3, and it uses a second tuner on the device. (This is also how SiliconDust's software works.)
Another way of achieving this is that Channels would request the full physical channel 32 and receive that from the tuner. Then Channels asks the tuner to filter out unwanted subchannels, leaving only 4.1. Later if you additionally wanted to simultaneously view 4.3, Channels could change the filter to also include that subchannel. Channels would then handle distributing the filtered streams (a mixed stream with 2 muxes, which Channels then must separate and feed separately to the different clients). This is the way some other DVR software works, like Tvheadend.
ATSC3 allows for up to 4 subchannels on each physical channel. So, while technically Channels could handle the situation in the second manner described, it's unlikely that it will. The process will probably continue much as before, as in the first situation described.
(Bandwidth is also a concern. The HDHR5-4K will only have a 100Mbps adapter, while physical ATSC3 channels can have a maximum of 57Mbps. So, it's easy to see that by using the second scenario of having Channels filter the muxes could easily overwhelm its network adapter. ATSC1 has a maximum bandwidth of 19Mbps for each physical channel; this means that is all 4 tuners we're delivering full bandwidth channels, that would be just under 160Mbps.)
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um...what? why is it not 1gig NIC (1000Mbps) in it? it woudl need that for 4K streams and load of other streams. if each stream is up to 57Mbps
From the FAQ page:
The HDHomeRun QUATRO 4K supports streaming 4 virtual channels at once.... 4 channels won't max out a 100Mbps link.
https://www.kickstarter.com/projects/1275320038/hdhomerun-atsc-30/faqs
The 57Mbps is for the full physical channel, which can hold 4 subchannels. Therefore it stands to reason that each filtered "virtual channel" you would tune would only be 15Mbps.
Just like the 19Mbps for ATSC1 is for the full physical channel, including the HD primary channel and all of the SD subchannels.
So, by allowing each tuner to only hold a filtered "virtual channel", the total bandwidth would only be about 60Mbps for 2 4K ATSC3 channels and 2 HD ATSC1 channels. It's using this scenario that allows SD to claim that 100Mbps is sufficient.
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i recall some massive issues that Prime users had of the thing falling off their network. The port on it was gigabit. and putting it on a 10/100 switch solved their issue. I think it was something in the NIC firmware that had a bug. I never had the issue my self, but read plenty of users that had the issue.
I had that particular issue with my Primes. It was due to a bug in their ethernet firmware that was finally fixed after nearly 2 years. (Forcing the devices into 100Mbps with a modified cable was one solution; partitioning the devices into a private link-local 169.254/16 network was another.)
The bandwidth issue for the HDHR5-4K is the same as with the Prime 6: the capability of the tuners themselves is means the device may have more bandwidth coming in than it can push out, leading to possible network issues. While it would be a rare thing for such a situation to happen, it definitely could. The fact that SD knows this and still chooses to ship devices with inadequate network bandwidth is a decision on their part.
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you are enjoying ATSC 3.0 while Poland not get full DVB-T2 until 2022 
I didn't back this project yet...but I would be interested to see how well my Synology 918+ handles the 4k streams.
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I can tell you that I can’t get my 918+ to transcode a FiOS 4K stream. Not sure if this is a bug as I reported it but didn’t hear anything as to whether this was expected or not.
That might be different being that its coming in thru TVE right?
Did you mean ATSC 3.0? I’m not aware of any TVE content that is 4K…
The FiOS 4K recordings were likely made from a cable feed through a Prime—FiOS broadcasts some sports content in 4K.
While the HDHR tuners and Channels handle the straight 4K HEVC content fine, I was unaware of transcoding issues with it.
That’s correct, it was recorded with a HDHR PRIME — sorry for any confusion. The errors I got back in February when I tried to transcode are here. We have since deleted the file in question and since we aren’t exactly getting any sports currently, I don’t think it’s possible to record more in the near future.
hopped on this this morning. does anyone know of a good website that talks about ATSC3.0 rollout?
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I can't find anything definitive on specific roll-out dates, but the main website is https://www.atsc.org/
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This is cool, but... Is anyone else a little confused/annoyed that SD has focused so intently on a product that can’t even really be used yet, while the Prime 6 has been nothing more than an empty promise for 2.5 years?
Yeah, that’s insane. Problem is that people wholeheartedly jump into these kick starters with companies that have yet to deliver on the last promised product. Also, kind of annoying to see Channels jump all over this while we’re still waiting for basic 4K playback of local content that’s been in Alpha/Beta for what seems like an eternity.
The Prime 6 was not offered thru a Kickstarter, and besides that poses a whole different kind of development challenge, is subject to CableCARD consortium approval, and is reliant on specific kinds of chips that were discontinued by the manufacturers.
I fully expect to receive my Quatro 4K in a reasonable amount of time. Seems to me the biggest problem with the Prime 6 is that they pre-announced it when they didn't have to, as they admitted in this explanation I recently reshared in another thread:
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