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The 2-stories house is equipped with a coaxial cable that has wall plugs in 1st and 2nd floors (it's also connected to the antenna on the roof).

Our IAP installed a modem for Internet (Arris CM820C) which frequency ranges are, according to the manual

  • RF downstream: 108-1002 MHz
  • RF upstream: 5-65 MHz

The modem is on the 1st floor.

Wifi is not powerful enough to reach the 2nd floor from the 1st, and a PLC test was not fully satisfactory.

So the next device "on trial" is a MoCA 2.5 Network Adapter for Ethernet Over Coax (Hitron).

  • The "TV" plug would be for the modem
  • the other one goes to the wall (first floor)
  • then the other Hitron device would be connected to the 2nd floor coax socket, delivering Internet from the 1st floor.

The frequency range is 1175 to 1625 MHz according to the MoCA 2.5 specs page 12 (2.1.4 MoCA 2.5 Extended Band D Frequency Plan), range divided into several channels.

Based on that,

  • is there a risk of interference between the IAP modem and the MoCA 2.5 Hitron?
  • is there a channel to choose preferably on the Hitron?

(Not sure it is possible to change the IAP modem channel)

Déjà vu
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  • I don't mind the -2, but at least knowing why the question is dv would help :) – Déjà vu Apr 14 '22 at 16:55
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    Probably because it's about the use of electronic devices rather than electronic design. – Finbarr Apr 14 '22 at 17:03
  • Actually it's not, see the answer from @hacktastical . – Déjà vu Apr 14 '22 at 17:11
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    Actually, it is. Calling this a "technology question" doesn't make it on-topic. It's still a *use of* XYZ electronic device(s) question - which is specifically off-topic. This stack is for questions about the *design* of electronic/electrical stuff, so if you had a question about the use of MoCA technology in your design, then great. But as your question currently stands, you're basically just plugging A into B and asking if it'll work. – brhans Apr 15 '22 at 08:53
  • @brhans My main concern is the conflict / interference that may occur (or not, that's the question) due to 2 devices sharing the same cable and using quite close frequencies (while they're not exchanging to each other). This is more an electronics related question, and I don't think a "super user" kind of site can answer that kind of technical problem. Maybe people here didn't read fully the question... – Déjà vu Apr 15 '22 at 09:08

1 Answers1

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So as I understand it:

  • existing house coax is two downfeeds from the roof antenna (probably RG59 cable), from a splitter, one feed for each floor
  • cable modem has new RG6 feed installed from the service on the first floor

So I am going to assume there is no physical connection between house coax and the IAP (service provider) feed. This is normal practice; if you require additional feeds they will generally install new RG6 for them.

With that all said, what you do depends on your system goals. I'm going to assume that like most people you probably don't care about cable TV and only want internet (if you did, the service provider would have installed new feeds.) If that isn't the case, make them come back and do it because, hey, free RG6.

On the other hand, you may want to use that rooftop antenna to receive free-to-air TV.

Can you use MoCA? MoCA can coexist with cable or over-the-air TV, no need to worry about channel selection, they use a higher band than TV and cable modem. MoCA can even work over RG59 if the runs are not too long, but it might work better if you upgrade your house coax to RG6 which has lower losses at high frequency. You can try it and see. MoCA is pretty robust though.

MoCA signals pass through splitters, but you may want to upgrade those too.

If you wish to keep your rooftop antenna you will need to install a MoCA blocking filter between the antenna and the house wiring so that you're not transmitting your MoCA to the neighborhood. Your adapter may come with one, if not, they're easy to order. Otherwise, disconnect your rooftop antenna.

I've used MoCA together with wifi range extenders / access points and it works, but it was somewhat complex to maintain (and at the time my day job was designing that stuff, as well as DVRs.) So, yes, the Hitron MoCA bridge can work with the access point of your choice.

You could also consider installing a hard-line Ethernet cable from the modem to the second floor. Then you don't need to install MoCA adapters at all. This is easier to maintain and more reliable in my opinion.

hacktastical
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  • Yes, we don't care about cable-TV. The hard-wiring between the floors would be optimal, of course, but there is no decent way to run a cable from downstairs to upstairs. Upgrading the coax to RG6 looks like a pretty heavy task! And in that case, why not installing a network cable :) So if I understand your answer, aside from the antenna filters consideration, there shouldn't be any interference / conflict (is maybe a better word) between the IAP modem and the new Hitron MoCA 2.5? – Déjà vu Apr 14 '22 at 16:51
  • Cable and MoCA can coexist on the same cable, it's designed to do that. It can also coexist with over-the-air TV. – hacktastical Apr 14 '22 at 16:57
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    Ok, great. You're the expert! Btw, as an expert, do you see why the question is dv? Doesn't it make sense? – Déjà vu Apr 14 '22 at 17:00
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    Some folks believe it's a 'question about the use of consumer devices' which they consider off-topic for EE-SE. I disagree, it's a technology question. Don't sweat it. – hacktastical Apr 14 '22 at 17:07
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    Well I'm used to SE, not much this site but others. It's just annoying that people dv on any occasion and anonymously. New users are discouraged by this behavior, which is a pity :( Not me at least :) – Déjà vu Apr 14 '22 at 17:09
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    100% agree. I've been pushing back on this ever since I joined. – hacktastical Apr 14 '22 at 17:16
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    @Déjàvu DVs are anonymous by design. The only thing de-anonymizing them would do is lead to a blow-up of arguments in the comments. – brhans Apr 15 '22 at 08:49
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    @brhans Highly debatable matter that comes back regularly... – Déjà vu Apr 15 '22 at 09:13
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    @All - And that is where the discussion about downvotes needs to stop. Downvoting is not the topic of this answer (and it is Meta anyway), so it is off-topic *here*. If you really want to discuss why downvotes are anonymous, go to Meta.SE (not our local Meta) - but as you probably know, the subject has already been discussed *many, many* times. This is a multi-faceted problem, with no *simple* solution (if the solution was simple, it would have been found, agreed & implemented already). Thanks for your understanding. – SamGibson Apr 15 '22 at 14:15