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boatlover said:
I have a question about splitters.

These outlets are Daisy chained together using 1 output of the splitter to feed the wall plate and the other output to the next splitter/wall plates. The spacing between outlets is about 8 ft. Only 1 receiver will be used in this room. This has worked well with my old Dtivo as the wife can move the furniture and there are not cables all over the place.

If I use the green label splitters will this continue to work with a SWM setup?

Thanks Dave
Nobody in the right mind would wire them this way.
In the simplest terms, a 2-way divides the power by 2, so:
first wall plate has 50%
second has 25%
third has only 12.5%
"and so on", reducing the signal by half each time.

As wallfishman has said, remove all the splitters and use barrel connectors to join the coax so you have only one wall plate connected.
 

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AntAltMike said:
Has anyone found a schematic for the internal construction of green labeled splitters? I am wondering if they diplex internally before splitting, and if the L-band isolation values are more normal.
I haven't and it would take opening up a good splitter to find out :)nono:).
I just tried to do some testing and couldn't get any indication that the SWiM isolation is any less than one that isn't green labeled. I can't say 100% that this proves the isolation is the same, but merely I couldn't find any sign of 10 dB or more difference.
 

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Floyd said:
Here's the specs from SolidSignal:
______________________________________________
8-way Wide Band Satellite Splitter, One Port DC Path

Satellite input frequency range 2 - 2150 MHz
Insertion loss 18 max dB
Isolation internal 20 @ 950 - 2150 MHz, 4 @ 2 - 30 MHz dB
EMI > 75 dB
Operating temperature range -34 ~ +60 (-30 ~ +140) C°(F°)
___________________________________________________

I suppose the isolation is less to allow for MoCA communication between the receivers connected to the ports on the green splitters. I think the frequencies used for MoCA are 5-40mhz, and there is more isolation at higher frequencies, since they are required to work up to almost 2000mhz to carry the 9 bands of data from the SWM unit to the receivers.
Mike: was the training for Phase1 or Phase2 ?
I'm just about to close on several DRE projects and now I have to go to Little Rock to take the Phase2 training before I can continue.
I'm not too sure of those numbers.
DECA is 475-625 MHz, and the loss between output ports has been measured @ 8 dB on the 2-way, 11 dB on the 4-way, & 14 dB on the 8-way.
The SWiM channels are 974 to 1790+ MHz, which I used to compare the isolation between a green 4-way & a Skywalker 4-way, but couldn't find enough difference between the two and the skywalker has 23 dB isolation.
The difference between 20 or 23 dB couldn't be measured, but since the DECA can be, and is "only" 11 dB, clearly the DECA frequencies are lower than the SWiM, and the 2-30 MHz must be higher than 4 dB.
 

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randyk47 said:
I noticed the other day that he didn't replace the old Zinwell four-way splitter at the SWM-8 with a green label splitter. Guess I shouldn't worry about that since it's working?
If the loss isn't too great, then the DECA will work. If you have either H/HR24s or H25, or even a HR34, you can measure the DECA loss between receivers.
 

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AntAltMike said:
So what I'm wondering is, are these green labeled splitters really just back matched taps?
I've seen the insides of both the non green & the green splitters and they're both based on a Wilkinson divider.
What I didn't get to see is the backside of the board of the green one.
"I suspect" there is a cap & coil to filter the DECA to a resistor circuit between outputs.
 

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randyk47 said:
I don't have any of those models so no way to measure. It's not that a green label splitter is all that expensive and certainly not hard to install so I guess I should just swap it out myself. I'm kind of a "if it ain't broken don't fix it" guy so I guess I can just ignore it. Since I'm not noticing any issues I assume the loss isn't great or significant enough to bother with.
So you have the DECA adapters on your receivers and the cLink will show a green status. Should one be yellow/orange, then you have reduced performance and need to change the splitter(s).
 

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AntAltMike said:
An AOL phrase search for web pages containing the term "Phy level loss" located only one. It was buried in the resume of an Indian Professor of compuer science named Mukul Goyal.

Searching for "Phy mesh rates" was more fruitful. There were two such pages found on the web. One was on DirecTV's own user forum and was posted back on August 8, 2010 by a tafiche, which is, or was, also the screen name of an infrequent contributor to this forum, but he (or she) hasn't posted here since August 11, 2010.

The only other internet page located by the AOL search containing that term was here, and authored by... VOS.
Not sure of your point or question here, "but" the receivers that do measure the DECA coax networking use those terms.
The DECA output is in the range of 0 dBm.
The dynamic range is about 45 dB.
When the loss is higher, the mesh drops, which reduces the network performance [bit rates].
Receivers that find mesh rates below 220, will report system test errors of reduced network performance between MAC addresses.
 

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AntAltMike said:
Several years ago...
I'm not sure what you're trying to do here, but you'll need to limit the DECA signals. With MDUs, they use bandstop filters at the POE, to keep the DECA within the unit. It's not intended for a wide range networking application.
If you're adding other signals into the feed, you'll need to keep them out of the 475-625 MHz band, and filter out the DECA from interacting with them, as it's a fairly high level signal.
 
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