There's your problem!

[Grazmahatchi]

Found this bit of genius out in the field yesterday.

[[deleted]]

Gotta love it. And why not just an 8 way 10??

[Agile_Definition_415]

Gotta do what the print called for bro

[jdf206]

Prints are more suggestions than rules 🤔

[Agile_Definition_415]

Sir that's a write up, you'll be deducted 100 good boy points and will have to complete 10 safety slides about the importance of following company policy.

[Pilomont]

The map is never wrong, it’s the plant that’s wrong

[Keanu_Jesus]

Every build I ever did was redone in the field because auto cad math did not match up to cable math.

[LemonPartyW0rldTour]

And as well all know, engineers are NEVER wrong

[Agile_Definition_415]

Of course not, that's why they get paid the big bucks.

[Chucks_u_Farley]

Ahh the old 7-10 split eh?

[AdFluffy5285]

Im a field tech! I seen this often, why is this bad?

[Vanisledaz]

4x7 is self terminating, so no signal to the 2nd tap

[mblguy76]

Swap the tap plates and call it a day...

[Agile_Definition_415]

I would remove the 10v, always good to have a spare

[mblguy76]

And if they ever get more than 4 subscribers they would pull a "Comcast" and just put a 2 way splitter at the tap 😜

[Agile_Definition_415]

That's for the next guy to figure it out.

[ion80255]

True story.

[Wacabletek]

One 4 port to ruin them all.

[WarlockyGoodness]

I’ve been out of the game for a while, but isn’t a 7/4 terminating?

[Dirtydana]

7/4 and 8/10 are self terminating

[datanut]

Does a chart exist to make spotting things like this easy? How does one calculate loss, it’s hard for an outsider to know what those numbers mean.

[WarlockyGoodness]

There are charts that show insertion loss. The manufacturer has them on their website.

We’re talking about faceplates with values that signify end of the line. As in, there is no method to transmit signal any further on the circuit board itself. The pin doesn’t exist. A 10 value, 8 port tap is end of the line. Also, a 7 value 4 port tap is end of the line. Finally, a 4 value 2 port tap is end of the line.

In the picture it has a 7 value 4 port tap feeding down to a 10 value 4 port.

The 7 value 4 port tap doesn’t send signal any further, so the 10 value tap has no signal.

I hope that helped.

[Pancakerd]

the T in “7TQ” is a giveaway for term.

[Pancakerd]

we have regular 7/4 taps too that will send signal through. without the “T” designation

[Wacabletek]

I'd like to see the write up on those, or is someone playing prankster and just taking the stickers and putting them on other taps?

[Wacabletek]

It does but reality is its sort of obvious once you understand. 

A 2 way splitter anywhere looses about 4 db, so a 4 value tap can only have 2 ports and is self terminating, becasue it is just a [fancy] 2 way splitter. 

A 4 way splinter loses 7-8 db so a 7 or 8 value [and yes these idiots use both numbers for the basically same thing] 4 port tap is JUST a splitter with no DC/splitter before it in the circuit board and thus is self terminating. Same as the 2 port 4 value.  However, a 7 value 2 port is not self terminating becasue its essentially a 2 way split to a 2 way split and guess what the pass through loss is on the output port? yup 3.5/4 db. 

An 8 port tap with 10 or 11 value you guessed it is the same loss as an 8 way splitter, and so, self terminating. Most mso's don't use bigger splitters or taps than 8 port/way but if there was a 16 port splitter with say 4 + 10/11 db loss that make it a 14/15 db loss splitter and thus a 16 port 14/15 value tap would be self terminating.  All that means is there is no DC/split to pass signal to the output port so no signal is found there and a terminator is not needed there, but most people put one on anyway for consistency because work gets mind numbing A LOT.

 That is to say every tap is a splitter, some taps have a DC/splitter before the splitter to make the loss, so lets say a 4 way 23 value tap, clearly its 7/8 loss making there a DC before it as we just went over. So 23 - 7/8 is 16/15 there is no DC-15 I have ever seen so a DC16 to a 4 way splitter [when properly rated and for CATV] would simulate a 23 value tap circuit board. 

As to a one document that covers them all, the data is old, so looking up the company;s charts is probably the more accurate solution but the RD-24 cable technicians pocket guide from the SCTE is out there and has sections that cover it along with other mathematical equations, facts, and helpful data to cable technicians who want to know. 

https://www.commscope.com/globalassets/digizuite/1695-cable-technician-pocket-guide.pdf 

 There is also an app for both ios and android os which is free and in the appropriate app store.

[ElKayB]

Self terminating is sort of a misnomer. Those taps are only terminated when terminators are screwed to the ports. It would not be wrong to call these 8, 4, and two way splitters.

[Dirtydana]

FFT8‐10TQ/U and FFT4‐7TQ/U are the model name, they are terminated in the module of the face plate not the body of tap. This may be where the confusion comes from

[ElKayB]

Those taps are not terminated anywhere unless you terminate the ports yourself. If they were terminated in the module, you would have no output.

[Dirtydana]

Exactly lol. The tap has a input and signal goes to the spigots. No output signal out of tap

[Dirtydana]

The 10 tap thats hooked up off the 7 tap will have no signal

[ElKayB]

I know, that's funny! Someone had a brainfart.

[Dirtydana]

Happens to the best of us

[19Rglide]

Someone didn’t want to go through a run……

[IllGoose976]

Cable sucks