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Diplexers in 3 decoder XV and UV setup

Red Carpet

Re: Diplexers in 3 decoder XV and UV setup


1. There are two ways to setup XtraView these days. The original called XV for identification purposes, and the new way called UniView (UV). XV requires an HB cable connection between the decoders from the RF ports on the decoders. UV feeds the HB via the SLNB cabling, thus avoiding the need for a separate HB cable.

2. NOT ALL decoders can receive or transmit HB via the LNB ports on the decoders.

These are Explora 1, the HD decoder 4 series models 4U and 4S, as well as ALL the older decoders that were XV capable.

3. The Explora 2A, 3A both have internal diplexers, which means the HB can be transmitted/received via the LNB port. The 5-series HD decoders are the same. These decoders are thus fully UV capable and don't need a separate HB cable between the decoders.

4. The SLNB LMX 500 and 501 have universal ports, BUT HB cannot be transmitted through the Universal ports, only through the Unicable ports. The LMX 502Z has NO universal ports.

5. It is generally NOT a good idea to mix the two types of XtraView in one installation

simply because you end up not knowing what is working and why.

6. As the Primary decoder here is an Explora 1, The HB will ONLY be available via the RF ports. As there is already an HB cable connection between two of the decoders, it makes sense that this process should simply be extended to the third decoder. ALL the decoders in the mix have RF ports and ALL can't receive HB via the LNB ports on the decoders.


All the decoders are however SATCR capable, and therefore it makes sense to connect them all to the Unicable ports on the SLNB, and NOT use the Universal port at all on the SLNB LMX 501.


Now comes the decisions.

Are all the decoders in the same room?  IF no then the HB cabling becomes a challenge.

That is why presumably, MC invented the UV system.

BUT IF there is already a need to distribute RF to other TVs to be able to "see" any decoder anywhere, then why not use the traditional XV setup?


So what is happening here is and is not clear from your descriptions so far is that the ONLY way these decoders will work, is IF there is an RF cable connected to all three decoders providing a path for the HB signal.


You ONLY need diplexers IF you want to do away with the HB cable, AND don't need to distribute RF around the home, and the decoders are all in different rooms.

THEN in this setup, a Diplexer will be required behind each decoder, and only IF all decoders are connected to the Unicable ports on the SLNB.


You won't get to the bottom of all of this confusion until you go and see or get your client to draw out ALL the connections showing very single cable connection, especially how any RF distribution is taking place.






Octo LNB; 2 by 2x4 MS; 2 by ES 5-2; Dedicated PSU for LNB, ES's, MS's; HD PVR 4P x 2; Explora 1; DSD 660; FSM

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Re: Diplexers in 3 decoder XV and UV setup


In this 3 decoder XV and UV setup the Explora 1 (Primary) is connected to the SLNB (Unicable), the HD 4S (1st Secondary) to the SLNB (Universal), with RF cable for HB from Explora 1 and the HD 4U (2nd Secondary) to the SLNB (Unicable).

For HB distribution from Explora 1 to the HD 4U (2nd Secondary) I tried the AS2F (Single DC port) splitters at both the Explora 1 and the HD 4U (2nd Secondary). But as you already mentioned it does not work like that and is clearly under standable to me. I left the AS2F splitters out of the system and asked my client to buy the correct diplexers at multichoice, as my supplier did not have stock. Meanwhile I connected the SLNB cable direct to the LNB IN on the HD 4U decoder only to get signal and channel 100 to work until he could get the diplexers.

Now comes the strange part. He later that evening informed me that the UV is working and I made sure with him if he was getting all the channels etc. Somehow, without the diplexers at the Explora 1 and the HD 4U (2nd secondary), everything is working fine according to my client. To my knowledge the Model 4U/S decoders do need HB from the primary through either RF cable or the SLNB with diplexers connected. After 2 days now it is still working with only the SLNB cable connected to the decoders. Is there any explanation for this?



Red Carpet

Re: Diplexers in 3 decoder XV and UV setup

The AS2F splitters are 5 - 1000MHz devices. Absolutely useless for this purpose as you need a device that goes all the way to 2500 MHz at least. You could try a 5 -2500 MHz splitter with DC pass on one leg. Also, avoid using the RF OUT ports on the decoders. rather use the RF IN ports for HB.

So are the DC blocks! Really bad advice you were given there. very lucky if you get that to work.


Rather get diplexers --- must more certain long term solution.


As these are all old decoders, an alternative to diplexers would be to use an old fashioned HB cable between the three decoders and not try and feed the HB via the SLNB.

Octo LNB; 2 by 2x4 MS; 2 by ES 5-2; Dedicated PSU for LNB, ES's, MS's; HD PVR 4P x 2; Explora 1; DSD 660; FSM

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Diplexers in 3 decoder XV and UV setup


A) I have a Explora 1 (Primary) and HD 4S (Secondary) already connected for XV via RF cable for HB. The RF(HB) cable is connected to the RF IN on the Explora 1 and RF OUT on the HD 4S. All working fine. Now I'm adding a 3rd decoder (HD 4U) to the system, but as always in this case I'm connecting it to Unicable on SLNB and using Diplexers at the Explora 1 and the 3rd HD 4U decoders. The diplexer at the Explora 1 and the HD4U decoders are connected as follow: "I/O" cable to diplexer from SLNB, "SAT" cable from diplexer to Unicable in/LNB in on decoder and "ANT" cable from diplexer to RF OUT on decoders. This is under normal surcumstances.

B) Now my problem is that my supplier is out of stock with diplexers. Okay I can buy from Aerial King or Multichoice but I also were informed that one can use a AS2F (single DC Pass) splitter OR a AS2F (both DC Pass) with "DC block" on one leg, as a diplexer. I have tried it in the above setup but without success. I connected the AS2F splitters (single DC Pass) as follow: "IN" cable to AS2F from SLNB, "RF OUT (DC)" from AS2F to Unicable/LNB in on decoders and "RF OUT (Non DC)" from AS2F to RF OUT on Explora 1 and 3rd HD 4U decoders.

All I need to know is if I'm connecting it wrong in the above setup (A) or was I not informed correctly (B)? Thanks.