Signal Splitters

[Guest]

If I have a DishPro Twin LNB and two receivers, and I just want to use the two receivers, can I use a satellite signal splitter to split the two outputs into four? I want to be able to move one receiver (along with the TV) between a bedroom and the computer/entertainment room, and the other will stay in the family room but I want to put a satellite outlet at either of the two cable drops. (i.e. both receivers will not be on one feed at the same time -- or does that work with DishPro equipment?)

[scooper]

DO NOT USE SPLITTERS ON SATELLITE INPUTS ! PERIOD !!! If you want to move receivers around (not advisable with PVR units), wire it up like 4 receivers.

Is there any reason why you couldn't pass on modulated signals to all rooms instead ? This would be a LOT easier to do and should accomplish the same thing ....

[MarkA]

As long as both receivers won't be on one feed at the same time you're absolutely fine.

[Guest]

Great, contradicting answers.

I just had to blow money for the new DishPro LNB and old receiver to DishPro adapter since the old-style Twin LNB that was in use decided it wanted to flake out and not work on the B output, so I don't want to get a SW-34 unless there's a need (no locals for my DMA, and nothing interesting on 61.5 (can't see 148)).

[MarkA]

It should be absolutely no problem, except for signal loss. Use good splitters, of course, and high quality cable and there is no reason you should have a problem. There will be signal leakage, but I doubt very very it will matter for your application.

[scooper]

I still maintain DO NOT USE SPLITTERS on DBS inputs. It is certainly not the way the receivers were designed to be operated...

And again I ask - is there ANY reason that sending modulated signals (i.e. normal TV RF via coax) wouldn't work better ?

I'm using this to do just that www.smarthome.com/7717.html (although I did find a place that had them for less)

[Chris Blount]

This is a very interesting question and looking at it from an electronics standpoint, it is NOT a good idea to use a splitter. Not only are there signal loss issues, but the line impedances will change which could damage your receiver over time.

You're best bet is to "broadcast" the output of the receiver to another room using Scooper's suggestion. I have this wireless system that works great.

http://www.buy.com/retail/product.asp?sku=90048336&loc=111

[Geronimo]

I agree. Use the right cable. And use switches not splitters. you cannot guarantee that the receivers will neer both be on a tthe same time. Do it right and avoid problems.

[Boba]

As a dealer let me stick in my two cents. TV splitters are designed to split over the air TV signals 2-69 with no voltage on the lines. Satellite signals carry voltage on the line to power the amplifiers at the dish and switch polarity, normally 12 & 18 volts D.C. TV channel 69 is in the range of 830 Mhz. Dish Pro frequencies are from 950Mhz. to 2150Mhz. considerably higher than TV channels.

[MarkA]

Boba, it's not hard to find splitters rated to 2.2 GHz.

[AntAltMike]

The signal loss of a splitter in that application will be about the same as the signal loss over about 50 feet of RG-6 coax. It will be of no consequence. There will be no impedance or leakage problems. Nevertheless, if you remain concerned about leakage, ingress or theoretical impedance mismatch caused by leaving a splitter port unterminated, you can cap the unused ports with Chanenel Master #7184 DC blocking terminators.

The potential problem will be that some day, you or someone else might inadvertently connect two receivers to the same splitter and damage one or both of the receivers. Channel Master and Sonora both make special "diode-steered" splitters that protect receivers from damaging each other if they are inadvertently connected in conflict with one another. The part number of the Sonora product that I am looking at on my bench as I type this is HRvS2. Channel Master's part number is 2212IFD. They are also nice to use if you are sourcing two multiswitches from one LNB and are concerned that the 18 volt sources might not be at exactly the same potential and might potentially conflict with one another.

One undesirable consequence of using diode-steered splitters is that they have a forward voltage drop of about .8 volts. I would advise keeping your coax runs to under 200 feet in length, since if they are much longer than that, there is an increased likelyhood that the 18 volts DC will drop to below 15.5 volts and call for the wrong set of signals.

[Chris Blount]

Mike,

You are telling me that leaving a cable with a splitter with one branch unterminated will have very little consequence? Oh sure, it might work for a while but I have a hard time believing that it won't eventually hurt the LNB and/or receiver. I would also think that the engineers at Dish would strongy disagree with you.

[MarkA]

It won't Chris. If you can show me a receiver harmed by doing so, I'd be shock. It won't throw anything out of tolerance levels for the receiver. The engineers at Echostar HAVE to disagree:) Because they don't want to lose their jobs if something goes wrong... You're not supposed to do this setup, but doing so is harmless. My DISHPlayer is hooked up this way (cable splitter in wall and impossible to access). Other end isn't terminated. Too lazy to run new cable. The installer said it would be fine, and it has been. And the advantage is, if I ever feel like it I can take the receiver down to the other room.

In short, this is something the OP will be doing at his own risk - but it would be nearly impossible for any damage to occur. Electronics really aren't AS sensitive as many people believe. A long run of low quality RG59 could cause a similar problem - but I've never heard a report of that actually happening.

[AntAltMike]

Originally posted by Zac
My DISHPlayer is hooked up this way (cable splitter in wall and impossible to access). Other end isn't terminated... The installer said it would be fine, and it has been.

You got lucky. Most cable splitters do not pass power and would impede the LNB switching. Also, most cable/off-air splitters I have checked that were rated up to 900 Mz roll off unacceptably starting at about 1.3Gz and clip off the top few transponders.

[AntAltMike]

Originally posted by Chris Blount
Mike,

You are telling me that leaving a cable with a splitter with one branch unterminated will have very little consequence

I am not making that broad a claim. I am saying that leaving a power-passing satellite splitter rated for L-band performance unterminated will have no adverse consequence on satellite signal.

Leaving a cable splitter or a broadband splitter rated for and used for both broadcast and satellite signal unterminated can allow ingress leakage on local channels if it is within a couple of miles from a local TV transmitter, but that symptom will only appear on the nearby local broadcast TV channel. It will not adversely affect the satellite signal quality or the LNB powering or switching.

[MarkA]

AntAltMike, I agree I got lucky. Most splitters will not allow this to work. However, 2.2GHz rated splitters that will work are becoming very common

[AntAltMike]

Originally posted by Zac
... 2.2GHz rated splitters that will work are becoming very common

But 2.2 Gz splitters that pass power on both legs are less common. Have you ever tried using a satellite receiver on the other leg in the other room? It probably will not be able to call the even numbered transponders from that location.

[MarkA]

Yes, it works fine. Again, the splitter is buried and I don't know how good it is - but based on the cable (CHEAP RG-59) I'd assume it's only rated to about 900MHz. But my main disagreement with Chris was about receiver damage. Even if it doesn't work, the chances of receiver damage are very slim. And again, my experience has shown that it works - but isn't ideal. It drops my signal a few points compared to connecting the receiver outside. But I'm too lazy to fix the setup when it works:)