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Combining 2 antennas into 1 or visa versa

Nice try, but Monster Cable Spec their splitters “port to port” drop in signal.
This includes the 3dB for a 2-way splitter or 6dB for a 4-way etc.
So your example is in fact 0.5 ~ 1.9dB (not 3.5 ~ 4.9dB). See the difference?
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Here we have a 4-way splitter having 6dB (signal /4) + 1.4dB insertion loss = 7.4dB per port drop in signal.

Not coined by me, but strictly it applies to atmospheric losses between antennas. I thought my use of the term would be clear.

Can you please show me their specs in which they mentioned “Port to Port”? There is no such thing mentioned on the label of their splitters.

Seriously?

Here is a Monster cable 8-way Low Loss splitter. 12dB per port drop in signal.
I would have thought the logical progression was obvious - alas I have been proved wrong.

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@geckoVN
I think me and you are saying same thing, but in a different way, causing communication problem.

My approach is as follow:
I will base this on a 2-way splitter to make it simple.

  • If the insertion loss specified by manufacturer/seller is less than 3 dB, obviously the manufacturer is using a way to specify in which 3 dB loss due to division of signal into two halves is neglected. This makes his product appear as low loss. This is similar situation like some manufacturets of antenna use dB and some others use dBi.

  • if the specified insertion loss is between 3 and 5 dB, and splitter is from a reputable manufacturer, I will accept it.

  • if the splitter is low cost tv/satellite version, and insertion loss is not specified, then I will take it 5~6 dB.

I think the problem arose when @Nitr0 said and was then contradicted.

If you look at the link he provided the spec sheet says low insertion loss, 0.25 dB typ

@abcd567 then contradicted saying

That is the internal loss or insertion loss is 8 to 20 times (in dB) worse than the specs quoted by the manufacturer.

This has never been clarified so stands as the statement that created the following discussion.

Unfortunately, that was not made clear at the time and @abcd567 referred to a particular splitter quoted in a specific post. The manufacturer quoted 0.25 dB but the quote said Practically there is an additional internal loss of about 2 to 5 dB depending on quality of the splitter.

As I pointed out in another thread incorrect information needs to be removed so that it doesn’t become fact and quoted well into the future.

S

edit: just fixed a spelling error.

1 Like

@SweetPea11
@geckoVN
The post I have quoted was not specific to minicircuits 0.25 dB splitter. That quote was only a part of the post about low cost splitters generally available in market. If someone visits the post I have quoted and read it in full (and prefeeably posts before and after), this confusion/contradiction will be cleared.

That was certainly not clear and there was no indication at the time to go and read the full post or the posts either side, but you then go on in the quote to say

and then you say that for the cheapest splitter

The contradictions are obvious!

As I said previously,

BTW I have tested my splitter/combiner and found that the isolation and insertion loss figures are within spec.

EDIT: Spelling

There is your first mistake.
A datasheet from a company like MiniCircuits is not meant to be simple, it is meant to be precise. It is meant to provide information to people who can understand it.

If you want to compare a 2-way to a 4-way splitter, it is simpler if the insertion loss is specified separately.
Anyone who does not understand that a passive splitter divides the available power between the ports is not their target market.

As for your:

They are “T’s” not splitters.
(except for the bit of garbage at the bottom - that’s just an embarrassment).

T’s and splitters are not “the same” and are not interchangeable.

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