Combining SAT signals and Full Digital Cable Service

[hd fan]

I am currently having an issue with the Rogers on Demand Service (and therefore no SDV channels available either) on the 3 TV's that have Hispasat and the Rogers Digital Setbox connected to them. I am using Ecoda diplexers at the TV's end and a 3x4 Eagle Aspen Switch. Basically the Sat signal is strong (61Q on Viewsats boxes (strong V muxes) and even stronger 73Q on the strong H muxes) but the Rogers digital cable boxes are working in Broadcast mode only (no IP address) since the 19 Mhz Reverse Data Carrier apparently can not link the boxes to the Rogers servers. The rest of the Rogers Digital cable channels work great and levels are good including HD channels but the On demand and new Switched Digital Video (SDV) channels that requiere an IP address do not work. The STB are Scientific Atlanta and the 3x4 switch is rated to work from 40 to 2150 Mhz like most switches but I am affraid that they (pretty much like cheap drop amplifiers) do not let the reverse data carrier (19 Mhz) to comunicate back to the Rogers Servers. I even just installed today a PCT 15 db 1 output drop amplifier rated also to work 5 to 54 Mhz in reverse with no availability.

I think I saw an RCA 3x4 switch claiming to be Digital Cable Ready at a dealer recently and I will buy it tomorrow to use it but I wanted to see if anyone had any experience with this kind of set up or any usefull advice.

Thanks in advance.

 

[zamar23]

Why do you need to run Rogers cable through the switch? On what port? If it's rated 40-2150, how it can pass 19 without notable loss?

 

[Wescopc]

Diplexers and digital cable don't play well together. :rant:
Bob

 

[hd fan]

Cx has Digital cable but requires Hispasat for those Spanish channels not available on Rogers cable and new home was pre-wired with only 1 rg-6 to every tv location. Centre port is for Antenna/cable and diplexer at tv outlet will separte signals.

It does not have to pass 19 Mhz from Rogers to the cable receivers but on the contrary it has to allow the 19 Mhz carrier from the receiver to get to Rogers headend. There are 2 carriers for data in a digital cable system , a Forward Data Carrier or FDC at aprox 75 Mhz coming from cable headend and a Reverse Data Carrier that goes back to the headend at 19 Mhz , and this one is the one that the 3x4 switches are having problem with (I have tried 2 switches already)

Usually 3x4 switches only rate the forward link , from input to output , but hardly ever mention the return link (typically with high losses) and that is the problem . Apparently not all 3x4 switches are created equal. Those used by the DTH providers (like the Eagle Aspen) do not offer a return path for frecuencies from 5 to 54 Mhz requiered for some Digital cable services (depending on the cable company even the downstream internet link could be in that band). But in this case the cable modem has its own cable but I still have to share the cable for 3 Tv's (digital cable boxes + Viewsats receivers at each TV). On the net I have found some Digiwave's 3x4 that claim 5 to 860 Mhz but I am affraid that that is the forward normal link but the reverse link (signal going from cable box back to cable headend) will still have a high loss. I need something like those white PCT drop amplifiers the cable company use that also have a return path from 5 to 54 Mhz with only 1 db loss for a 1 output amplifier. I tried the amplifier right in front of the 3x4 switch but then QAM Tuner levels where to high at the STb's (tuner level should be between -10 to +10) at +15 dB and therefore some channels were even pixealeating.

As per the STB's diagnostics screens , signals levels are ok , even for the 19 Mhz RDC carrier but still the boxes are in broadcast mode (no 2 way communication) , in other words no IP address therefore no Rogers on Demand , and no new SDV channels available (some spanish channels in our area use SDV technology). No matter how many splitters I use or combine them , the STB's work perfectly , but as soon as I use the 3x4 , even fed straight from the incoming cable line, I have problems although sometimes 1 of them might work , but intermittently.

My point with the post was to save time and money buying several 3x4 switches untill I found a Digital Cable compatible one. I guess I will have to be the guinnea pig . Will post results if any. Lets hope that RCA 3x4 I think I saw weeks ago that says Digital Cable allows for a decent return channel and it is acctually fully Digital Cable compatible.

Thanks for the reply anyways.

 

[hd fan]

Wescopc as a matter of fact, the diplexers are not the issue. If it would have been a 1 satellite receiver system TV, a 2 diplexer solution would have worked perfect as it is working right now (all 3 cable boxes have a diplexer connected now but at the electrical panel I removed them from the 3x4 and used a 3 way splitter instead , no TV from Hispasat for that family until tomorrow or who knows when). and like I say it works with the diplexers connected at the TV location.

You know what , thanks for your comments , I just thought of using 2 High frecuency 2-way splitters and split both outputs of the dual LNB and fed those 2 to a diplexer for each receiver line (the kids are not acctually interested on the spanish programming since they watch mostly english shows but still I wanted to keep the 3 or 4 sat receiver system through out the house).

Time to go to sleep , will post results tomorrow , but heck they should manufacture more 3x4 switches that are digital cable ready.

 

[zamar23]

In what frequency Sat Internet communication is done? May be the switch that can handle sat internet will handle IP from the cable box. Just ask a Digiwave Tech, as they are in your area and should know this stuff, and may have the right switch.

 

[hd fan]

Ecoda 3x4 EC-3134ST did the trick for me. Funny thing is I tried 2 more 3x4 switches (used ones though but they work with analog cable or OTA) and even with the 15dB PCT Drop Amplifier right at the entrance , those IP-based services did not work. Finally today before going with the 2 2-way splitter solution I decided to try one more switch (I wanted badly to have the capability to feed up to 4 sat receivers in the home) , and this Ecoda was a blessing from heaven (I think I have never been happier in my life than after seeing the On demand services working (for what it is worth since most people do not use it at all but heck as a tech you have to make sure everything works ok and they are friends of mine).

Another funny thing is the cardboard box of the switch claims Ant Frec Range 5 to 860 Mhz then in the switch itself is rated like every other switch from 40 to 860 Mhz , but heck like I said it works. the only explanation is that is actually better designed to let the reverse carrier at 19 Mhz go back to the cable headend. I could not test it further though but will in the near future. I end up using the drop amplifier anyways since without it signal levels were quite low.

I would assume that by Sat Internet signals you mean providers like the ones Lyngsat lists therefore as you can see they use the same frecuencies that a regular Ku Tv signal uses. Zamar thanks for the comments anyway but you obviously lack the telecommunications background to tackel this problem accordingly. In other words , back in Havana , you would have been expelled from the University. Like 1 of our professors (Electric Circuits from 1 to 4, BTW the text book was also from an American Engineer) used to say; There are 2 kinds of mistake , regular ones like math or grammar related or the conceptual ones. From the latter ones, beleive me, no one escaped. lol. Zamar, I am obviously just joking you, lol.

 

[zamar23]

hd fan

Are you saying that your "communication background" helped you to resolve the puzzle? Or you just happen to have a switch that filtered less signal? Don't be upset, but I don't think you came close to approaching the problem professionally. It never starts from trying something you have at hand at the moment, unless that's what you learned in Havana.

In fact, you shouldn't perform installations without being trained, and the job does not even require high school diploma, just on-the-job training. I'm glad you were lucky to get away this time.

 

[zamar23]

You might want to read this: Cable Internet + Satellite on the Same Line

One can cause not only IP packet loss from the Cable Box to head end due to attenuation and/or ingress back to Cable TV line introduced by the Sat Switch or splitters & diplexers feeded from sat receivers, but at times also a lot of grief due to lost internet or cable service in neighboring houses due to a local nod amp saturation, and resulting problems to his customers from Rogers. That's only if he does the job unprofessionally, using components that happen to be at hand at the moment and mastering a setup diagram without knowing what he's doing. One may get away with it for some time though thanks to..."communication background".

 

[hd fan]

Like I said I was obviously joking, thanks for the link anyways.

Several similar (SDV channels just recently being used by Rogers Cable the only difference) setups (due to almost no one pre-wiring 2 RG-6 cables to every TV locations) are still working after several years, including where I live. This time I agree with you using both used 3x4 switches (I think they are both indeed the same make/model but no label anymore) might have been the issue. They were obviously not fully working properly anymore. Maybe because they look the same I acctually tested the sameone twice , who knows now.

Unfortunaelly I have no Spectrum Analizer to fully professionally determine what was exactly happening

 

[zamar23]

See, on forums like this people share setups they make in their own backyard. At this level almost anything is permitted, unless its grossly disturbing or dangerous for others.

When it comes to installing equipment to others on a regular basis, the threshold is getting a lot higher, in particular in training level, using adequate equipment and installation schematics. I don't think the install described here is adequate or professional in any way, its not a matter of merely using old switches. Compliance with local rules, regulations and practices is another untouched issue.

Just read, what people say on DigitalHome.ca about tinkering with Cable TV lines. It doesn't mean the solution isn't available, just that its not the recommended solution that you found.

 

[hd fan]

then which one is