I figured it would be interesting to test a number of common splitters for OTA/Cable use... do the Monster splitters actually perform any better than the $2.99 splitters?

After a trip to Fry's and a long day of testing...
http://www.silicondust.com/wiki/info/splitters

Nick

At what frequency/s are you measuring the losses?

Hi,

The main test frequency was 561MHz.

The thinking - if a splitter performs poorly at this mid frequency then its lower or higher frequency performance isn't very interesting :)

The surprise was the cheap splitter I picked up in Shanghai. I didn't give it a grade because it isn't available in the USA (and has the wrong thread for use in USA).

If I find another splitter in the <7.6dB loss range (possible challenger for the top spot) then I will compare lower and higher frequencies as well.

The comparison is for OTA/Cable use only. It does not apply to satellite.

Nick

could you explain difference of 'European style F connectors' ?

Thanks

could you explain difference of 'European style F connectors' ?
The thread is ever so slightly different.

Just enough that you can't screw on a US-style cable or terminator, but not enough that you can tell by looking at it :confused:

thanks..good stuff

I think you should give at least 2 other points: the flatness is important


say 100 mhz and 900 mhz

I don't give a rat's patooie if a splitter loses a dB more or less than another splitter. Analog TVs are designed to produce pictures indistinguishable in quality over a range of about 40dB of signal variation. Digital tuners will also, even though their manufacturers usually recommend a smaller input window.

Did anyone bother to put 75 ohm terminators on the unused ports of the supposedly more efficient, cheaper splitters? They will sometimes suck down the output of the measured port by a couple of dB, whereas the better engineered splitters will perform more evenly with and without loads on every port.

Cable companies care about RF shielding, so as to avoid exceeding cumulative leakage requirements. The quality of and design of the center conductor seizure mechanism is also a quality consideration because better materials and better design will result in better reliability.

The thread is ever so slightly different.

Just enough that you can't screw on a US-style cable or terminator, but not enough that you can tell by looking at it :confused:

Hard to imagine that someone here has even worse eyesight than I do. :eek:

I don't give a rat's patooie if a splitter loses a dB more or less than another splitter. Analog TVs are designed to produce pictures indistinguishable in quality over a range of about 40dB of signal variation.
For QAM 256 digital cable you need at least -12dBmV. Adding an extra splitter can take the typical -5 to 0 dBmV down to marginal levels. If you are planning out your splitter/wiring then it is good to know what the loss is through a splitter.

Did anyone bother to put 75 ohm terminators on the unused ports of the supposedly more efficient, cheaper splitters?
All tests had terminators on the unused outputs (meter + three terminators). The test was repeated 4 times per splitter, once for each output.

Performance without terminators varies dramatically - I have measured 15dB of loss from a 4-way splitter with unterminated outputs.

Nick

I don't give a rat's patooie if a splitter loses a dB more or less than another splitter.


yes well a DB here, a DB there loss adds up, don't you agree?

dB loss isn't the be-all and end-all of a splitter. I've got a rat shack splitter which causes ghosts; presumably a pretty bad impedence mismatch. Though I'd guess it would have high loss as well.

Be interesting to see results for the ones more marketed to professionals: Channel Vision (which claims 7db for a 4-way split, don't know what frequency), Regal, Pico Macom, and Holland.

If you are dying to spend $20-$30 for a splitter be my guest.

They tested about a half a dozen spliters. It is odd that monster came up on top. I don't by it or will I buy it. Why didn't they test Terk brand too?

There is probably a 1000 more models out there. I pay 75 cents/ea for mine.

$30= 40 splitters here.

I call BS on this test... Unless you have multiple test equipment. i.e. frequency generator, Qam source generator,spectrum analyzer, and good qam analyzer
(MER,BER,and error vector managment ) Sun Rise unit; than a splitter is a splitter..5-1000mhz

I figured it would be interesting to test a number of common splitters for OTA/Cable use... do the Monster splitters actually perform any better than the $2.99 splitters?

After a trip to Fry's and a long day of testing...
http://www.silicondust.com/wiki/info/splitters

Nick

Why would anyone bother to go to Fry's and buy a $20 and a $30 splitter to test them? The comparison page that jafa linked is at a site designated in his profile as his home page. Is he selling Monster splitters? Has he also successfully tested Terk and Spiralateral antennas?

Why would anyone who knows what Mhz are confine a test to one frequency? When I first scanned the linked page and saw four values for each tested component, I just assumed that they were measured at four different frequencies, since that is how the manufacturers of commercial products present their measured insertion loss figures, but that whomever collated the page neglected to include those frequencies in the legend.

Further, what use is a sample of one unit of each splitter?

Sources have imperfect impedance. A source who's impedance is not exactly 75 ohms at a given frequency will still develop maximum power across a load of identical or near identical frequency. For that matter, our FSMs are imperfect loads as well. I can connect two of my meters to the output of one device and one meter may read a dB or so higher than the other, but then I can connect those same two meters to the output port of a second device and the meter that gave the lower reading in the first test might be the one that gives the higher reading in the second test. This so-called test is silly. It is a salesman's test, not a technician's test. The disparaging references to the "cheap splitters" is a dead give-away.

In rare instances where I was strapped to conserve every possible dB because I was constructing a distribution line with over 150 feet of RG-6 and a dozen passive components, with no practical midpoint place to amplify, I measured the lowest losses with my $.39 splitters.

yes well a DB here, a DB there loss adds up, don't you agree?

It doesn't add up if you are using one splitter. You could also save a dB of loss by moving your TV to the other side of the room, or by rewiring with RG-11.

If someone has a distribution system that can be disrupted by one additional dB of signal loss, then they need to install a 10 dB amplifier. Signal can go up or down by more than one dB seasonally.

To really do this right you would need a network analyzer to do swept measurements of loss, return loss, and output port to output port isolation. The result would be many graphs for each splitter. It is quite possible that a splitter with higher loss could have better isolation and/or better return loss.

They tested about a half a dozen spliters. It is odd that monster came up on top. I don't by it or will I buy it. Why didn't they test Terk brand too?
Hi,

For the first pass we tested every splitter that Fry's Electronics carry. We will be expanding the list. The Terk splitter is on the todo list but I don't have one in the lab yet.

I call BS on this test... Unless you have multiple test equipment. i.e. frequency generator, Qam source generator,spectrum analyzer, and good qam analyzer
(MER,BER,and error vector managment ) Sun Rise unit; than a splitter is a splitter..5-1000mhz
We have QAM modulation and test equipment we use for our digital tuner products. For this test we used a NTSC source and a calibrated digital-readout cable signal meter.

Nick

For the first pass we tested every splitter that Fry's Electronics carry. We will be expanding the list. The Terk splitter is on the todo list but I don't have one in the lab yet

Rich075 was being sarcastic. Or is it facetious? No one here expects or wants you to test a Terk splitter. Besides, we already know what the results will be.

High School girl, on way to graduation, makes sarcastic remark, which her obtuse boyfriend takes literally.

High School girl, miffed, says, "I was beng ironic"

George Wendt replies, "Actually, you were being sarcastic. What's ironic is, you're about to graduate from high school even though you don't know the difference.
- From: The George Wendt Show

http://www.imdb.com/title/tt0785377/

http://www.tv.com/the-george-wendt-...ep_list;title;4


We have QAM modulation and test equipment we use for our digital tuner products. For this test we used a NTSC source and a calibrated digital-readout cable signal meter.

So you had the technical means and know-how to conduct a useful test but chose not to do so.

"We have QAM modulation and test equipment we use for our digital tuner products. For this test we used a NTSC source and a calibrated digital-readout cable signal meter."

Nick

What kind of analyzer and or meter did you use for the analog, also was this a 64 or 256 QAM and what was the compression of SD/HD channels plus how where the sessions built out? What meter was used for QAM mesurement?

Sorry to be a pain but what about your MER levels and Pre/Post BER on the QAM.

Coming up with a test that says monster is on top is just as bad around here as saying terk was on top.

Just does not offer much credibility and makes you wonder what is behind such a finding.

I bought my Electroline EDA-2400 4-port amplified splitter for $20. Same or less price than Monster and 7db *gain* vs 7db loss.

Sometimes people lose sight of the big picture when paying premium dollar for that last tiny bit of better performance.

Although it is worth questioning test results that show an overpriced splitter to be so much better a performer, I tend to view the outcome as being driven by the limitation on what Fry's had to offer.

A more interesting comparison - in addition to expanding the range of testing - would be to performance compare Monster, Terk, and other high priced splitters with lower priced perceived quality splitters commonly available online such as Holland, Eagle Aspen, and many others.

But the outcome of such a controlled experiment may not be very exciting, other than showing that some people have wasted their money. Given quality construction, there just is not that much of a potential difference between passive splitters.

If I find another splitter in the <7.6dB loss range (possible challenger for the top spot) then I will compare lower and higher frequencies as well.
NickConsidering that "6" dB is perfect split 4 ways, and most splitters are resistive, not transformer, 7.6 is darn good. The resistive ones I looked at on professional sites are 12 dB. I believe they can get them lower, but not without other problems, like real difficulties if unterminated. Even that requires reactive or torroidal, and are probably not inexpensive.