DaveH If it's just for personal use, how will you watch 220 channels at the same time?
Sometimes you want to have something just to have it 😃 In my case it started with I think 8 channels and then I started to ask myself how far I can push it, until I found the limit eventually. And then fine tuning it was more a challenge that I wanted to solve rather than actually useful. In my case the hardware was already there and it didn't cost anything to actually utilize it.
void walker Well not so much time and effort for him since it's already done ?
There's a big difference between something that works for myself and is based on a modified router which can now no longer be updated and runs an outdated Firmware and whatnot, and something that is a production ready product that someone else uses. Plus the whole SDK is highly confidential, so the first thing to do is contact MaxLinear and try to get access (which will be a nightmare, you should definitely be prepared to sign an NDA and be prepared to explain exactly why they should give you access). Then it's hardware development, which needs lots of experience to actually end up with a board that doesn't crash all the time for no reason. To be fair, they do provide reference designs but even if you use one of those, modifying it could still cause issues. Assembly is fun with the huge BGA CPU and (unless you change the reference design) the super small caps/resistors. Intel did hand-solder a few of their reference designs back when the Puma CPU Series was part of their connected home division and even they made some mistake in the design and had to use small wire to fix it. So you might not get it right on the first attempt. The alternative is obviously to buy a router and repurpose it with a custom firmware. It might not be a perfect fit then and have useless features (such as analog phone ports and WiFi or even DECT) but it saves the whole design process. In my case I don't have a port that is capable of more than 1 Gbit/s, so I had to use LACP to spread the traffic across two ports (which are internally connected to a switch with a 2.5 Gbit/s link to the CPU, and that whole setup brings a whole new load of challenges with it as it requires a few tricks to get hardware acceleration to work properly, which is an absolute requirement). As of today there should be routers available with 2.5 Gbit/s ports, so this mess is probably no longer necessary as of today. One last thing to look out for: The CPUs have secureboot and many manufacturers are using it, so many devices will not allow running a custom firmware at all.
If I'd start from scratch my approach would probably use the MxL268 from MaxLinear and then use an FPGA to process the data on the SerDes Lanes. If you do the demodulation yourself you're basically only limited by what you can put in the FPGA, if you let the tuner do the demodulation you're limited by 8 channels of demodulated data. Those chips are cheap though, so you could just add it 3-4 times and don't bother with the demodulation at all. Then it's a matter of filtering, adding a header and sending out the packets, that's where it gets easy. Broadcom also has Tuners/Demodulators in their portfolio, no idea if it's easier to get someone's from broadcom to talk to you though (probably not), and that's kinda a requirement if you want to buy those chips and get documentation for them so you actually know what to do with those.
Long story short: It's complicated.
IIRC there are Chinese tuners available for less than 1500 USD which stream 24 DVB-C channels over IP. You can even do DVB-S2 or DVB-T.
Also for the VU+ Receivers there are 8 Demodulator FBC Tuners available. One of those receivers can handle 2 FBC Tuners, plus another dual tuner. So if it's possible to shove in those tuners then you'll get 10 Demodulators in one of those receivers. That's low enough to not worry about the network interface being the limit. I'm sure if you do additional research you'll find similar solutions, maybe with even more demodulators. The BCM31586 chip has 16 for example, but no idea where that's used in real world applications as of today.
