Using cable splitter to supply more than one room

[sc00bie]

Hi, 1st post here and hope I can find out some usefull advice.

Currently an existing customer from when cable first started in Edinburgh. Phone service has been with them for around 15years now!
Ok so I am waiting on V+ box to be supplied and installed. Currently have a Pace unit for TV and have upgraded the package to XL. Broadband also supplied from them too, this is now up to the 20MB package.

When I bought the house it was gutted including a rewire. I had RG6 coax fed to each room for future installs of TV. The main feed comes into the attic where it is split for the broadband and TV, then there is 2 attenuator type boxes, one on each cable before dropping to the relative appliance.

I am keeping the Pace box and putting it in the kids room.

I tried putting a F type + 3.5db 5-1000 splitter on to the incoming feed after the exisiting attenuator for the TV, connected up the second feed to the other room and checked that I got a TV signal. Great.

I noted that I had lost Discovery channels. Taking the splitter back of and reconnecting just the one cable allowed them to return, so I put on another splitter without attenuation and again lost the discovery channels.

I am stuck now, I don't know what I really need to be able to distribute the incoming signal to the second room and maintain all the available channels, can anyone help with this please? :confused:

I have also noted for quite a long time that I get 'ghosting' when watching channels and most noteable when I listen to the radio, having spoken briefly to a VM tech he advised it was caused by the the scart from the Pace box to the TV, tbh I'm not convinced that this the cause, can anyone advise on channel crosstalk like this?

Thanks in advance -Sc00bie

[on in an hour!]

Hi, 1st post here and hope I can find out some usefull advice.

Currently an existing customer from when cable first started in Edinburgh. Phone service has been with them for around 15years now!
Ok so I am waiting on V+ box to be supplied and installed. Currently have a Pace unit for TV and have upgraded the package to XL. Broadband also supplied from them too, this is now up to the 20MB package.

When I bought the house it was gutted including a rewire. I had RG6 coax fed to each room for future installs of TV. The main feed comes into the attic where it is split for the broadband and TV, then there is 2 attenuator type boxes, one on each cable before dropping to the relative appliance.



I tried putting a F type + 3.5db 5-1000 splitter on to the incoming feed after the exisiting attenuator for the TV, connected up the second feed to the other room and checked that I got a TV signal. Great.

I noted that I had lost Discovery channels. Taking the splitter back of and reconnecting just the one cable allowed them to return, so I put on another splitter without attenuation and again lost the discovery channels.

I am stuck now, I don't know what I really need to be able to distribute the incoming signal to the second room and maintain all the available channels, can anyone help with this please? :confused:

I have also noted for quite a long time that I get 'ghosting' when watching channels and most noteable when I listen to the radio, having spoken briefly to a VM tech he advised it was caused by the the scart from the Pace box to the TV, tbh I'm not convinced that this the cause, can anyone advise on channel crosstalk like this?

Thanks in advance -Sc00bie
i dont know of any splitters we use that dont have a loss through their output scoob

[tucker61]

if you are having v+ as a additional box then don't the engineers move the original box for you when they come out?

[sc00bie]

Hi tucker61

Thanx for the reply. Yes they do move the original box through for you but in this case there is no feed to the room where it will be placed as the cable is not connected at the entry point to the house.... or do you mean they will connect the cable for the feed to the room as well?

on in an hour! - were you going to add something ? Ooopps! sorry missed the last line. This is where I'm stuck, using one that boosts the signal causes channel loss and one that doesn't same result !

[tucker61]

I am 99% sure they split and run the feed to where you want it for you.

Can Someone else confirm?

[on in an hour!]

Hi tucker61

Thanx for the reply. Yes they do move the original box through for you but in this case there is no feed to the room where it will be placed as the cable is not connected at the entry point to the house.... or do you mean they will connect the cable for the feed to the room as well?

on in an hour! - were you going to add something ?
i said what i was gonna say but it ended up in the middle of your post,so i edited it!! anyways,when they come to fit the set tops they should either run a new cable to the extra set top or connect up existing wire,either way they should then test the rf signal strength off the network to confirm its right at the back of both boxes ;)

---------- Post added at 19:54 ---------- Previous post was at 19:51 ----------

Hi tucker61

Thanx for the reply. Yes they do move the original box through for you but in this case there is no feed to the room where it will be placed as the cable is not connected at the entry point to the house.... or do you mean they will connect the cable for the feed to the room as well?

on in an hour! - were you going to add something ? Ooopps! sorry missed the last line. This is where I'm stuck, using one that boosts the signal causes channel loss and one that doesn't same result !
scoobs,splitters as i know them dont boost VM's signal,the only way to boost the signal is from the street cabinet ;)

[sc00bie]

Ok guy's, I suppose I'll need to wait and see what happens at the install.

17th jan tbc. will post back and let you know and hopefully for others too.

many thanx for your v quick replies and info :D
Scoobie

[PS1]

You could try and get your hands on something called a HDU. it wont actually increase the signal but it will prevent the signal loss you are getting through a normal splitter.basically it is just a powered splitter than doesnt cause the signal loss like usual splitters:D

[sc00bie]

Hi PS1,

Sounds like an idea... I found this one, seems to be Sky box related, therefore will it be compatable with the V+ box supplied by VM ?

http://www.audiovisualonline.co.uk/dynamic/eshop_products.set/ref/1948/labgear-hdu681-8-way-home-distribution-unit-with-2-lnb-inputs/display.html

[Jonnymeg]

The thing is, the signal must be really low in the fist place.

The ideal level for langley/bromley is -8db but in reality i have seen it working well at -17db. If you have a decent level you would not loose channels by using a splitter with a value of 3.5db.

I would suggest having the installer of your V+ look at the levels. Once it is installed you can see the power values in the technical screens.

[sc00bie]

Thanx Jonnymeg,

it's sounding like the best way forward. I'm not sure what the level currently is or what it should be. Only that neither of the splitters resolved the loss of certain channels.
I metioned that there is also ghosting happening which I thought may be too strong a signal or lack of channel separation somewhere, again neither of the splitters made it worse or bettter.
Theory then if the signal is strong enough, are the splitters filtering some of the frequency where these channels reside?

It is a bit mind boggling especially when there is the potential to increase or decrease the signal strength at the street and also through the box via it's own software (if poss).

Confusious say !
Cheers for the reply, Sc00bie :D

[Jonnymeg]

Re:ghosting
Are you connecting the cable feed directly to the TV? Or are you saying there is ghosting coming from the the STB? For example is there ghosting on channel 101?
Ghosting is not something that should be possible on digital TV unless you have the STB connected to the TV via RF.

Secondly:

If the signal is too low you will loose certain channels before others. So the loss of a certain number of channels is normal when the signal becomes week.

Third:
There is no way to increase the signal with software. the only way to increase it is to move the connection in the street cabinet or to use a thicker cable to your property.

Lastly:

You keep saying 'Attenuator' in your original post. Are you sure about this? Attenuators reduce signal so having these in is a problem. Are you sure you do not mean Isolator?
If they are attenuators remove them.....if isolators leave them in, they are like a fuse.

[sc00bie]

Hi Jonnymeg,

Ok points noted.

Info:

Supply in attic comes in and is split using a QQ69A 5-1000MHz passive splitter and features low insertion loss and high return loss and isolation.
Can be found in Maplins catalogue and recommended for cable TV only.
I used this to replace the original digitap 5-1000 -120db RFI splitter with both outputs indicating 3.5db. It does not seem to have made any difference and my thinking was to not reduce the incoming signal, (if this is wrong I will put it back on) as it was going to be split to other rooms.

Each split feed has a Tratec TRIS-102A fully isolated sytem outlet @ 5-1000MHz with an output shown as 0.4db. (if these are removed it causes a feedback drone through speakers and have been installed from the outset by cable themselves.)

One goes to the cable modem for internet, second goes down to the Cable STB (via a wall socket with F-type connector) using RG6 cable

Output from cable TV box is via scart to the tv.
I have a sony cd hdd recorder but it's not in the equation just now, other wise the output would have gone via this by scart, then to the TV using scart.

This setup currently provides all channels and the ghosting effect that I mention.
After checking the ghosting effect today and having reported this to VM it has misteriously stopped and nothing from VM to indicate they have done anything. I'll check it again tonight on radio station where it is most obvious, strange....

As you advise attenuation is to reduce the signal which is why I opted to use the passive splitter.
STB as above is connected via scart.
Only change I have now is the passive splitter instead of the digitap.

Something that has just occurred to me :idea:, the signal passes through the 0.4db outlets, if I changed the 2 way splitter to a 4 way (same passive type) then the installer would only need to connect the cable to the other room with the same 0.4db outlet, would this be the simplist way forward ?

My whole intention is to minimise the work the guy has to do, keep my house in one piece and minimise the hassel for my wife when the guy is here. Having unsightly cable routed around, skirtings and door ways is not an option, hence why I future planned for this type of thing.

So after the looong reply bet ur exhausted, time for a :beer:, cuppa etc.
Cheers - Sc00bie

[albion107]

HDU's do not boost the signals they only maintain the currentl level without the need for splitters.

[Jonnymeg]

Hi Jonnymeg,

Ok points noted.

Info:

Supply in attic comes in and is split using a QQ69A 5-1000MHz passive splitter and features low insertion loss and high return loss and isolation.
Can be found in Maplins catalogue and recommended for cable TV only.
I used this to replace the original digitap 5-1000 -120db RFI splitter with both outputs indicating 3.5db. It does not seem to have made any difference and my thinking was to not reduce the incoming signal, (if this is wrong I will put it back on) as it was going to be split to other rooms.

Each split feed has a Tratec TRIS-102A fully isolated sytem outlet @ 5-1000MHz with an output shown as 0.4db. (if these are removed it causes a feedback drone through speakers and have been installed from the outset by cable themselves.)

One goes to the cable modem for internet, second goes down to the Cable STB (via a wall socket with F-type connector) using RG6 cable

Output from cable TV box is via scart to the tv.
I have a sony cd hdd recorder but it's not in the equation just now, other wise the output would have gone via this by scart, then to the TV using scart.

This setup currently provides all channels and the ghosting effect that I mention.
After checking the ghosting effect today and having reported this to VM it has misteriously stopped and nothing from VM to indicate they have done anything. I'll check it again tonight on radio station where it is most obvious, strange....

As you advise attenuation is to reduce the signal which is why I opted to use the passive splitter.
STB as above is connected via scart.
Only change I have now is the passive splitter instead of the digitap.

Something that has just occurred to me :idea:, the signal passes through the 0.4db outlets, if I changed the 2 way splitter to a 4 way (same passive type) then the installer would only need to connect the cable to the other room with the same 0.4db outlet, would this be the simplist way forward ?

My whole intention is to minimise the work the guy has to do, keep my house in one piece and minimise the hassel for my wife when the guy is here. Having unsightly cable routed around, skirtings and door ways is not an option, hence why I future planned for this type of thing.

So after the looong reply bet ur exhausted, time for a :beer:, cuppa etc.
Cheers - Sc00bie


Ok, we have a full picture now.

There doesn't seem to be anything wrong with your set up. All the installer needs to do is change the first two way splitter for a three way one when he installs the V+. The connect the cable you already have installed to the extra room to the new output.
No problem.

It sounds to me that your signal is just to low at the point it comes into the house and splitting it again is just too much.

Lets say the power is -12 when it comes into the house. The first splitter will cause a loss of 3.5db which will give your STB a power level of -15.5db. Most stb's will just about work ok at this level.
Then when you inserted another splitter after the first you are now providing 15.5 minus another 3.5 making only -19db going into the box which will loose channels.

Does this make sense to you?

So what needs to be done is to up the power on the way into your house by either moving your tap point in the street cab to a higher level or putting in a thicker cable.
It is also possible that there are some dodgy f-connectors on the feed coming in that is causing a big loss.

There is no real way for you to test the power of the DTV signal coming in to give us a better idea but what you can do is look at the power supplied to the modem.

go to http://192.168.100.1/ and this will take you into the modem diag screens. In here you will find (look around) for the downstream power level.
The modem power is mostly higher than the DTV one so if yours is really low then we will have a good idea of the problem.


The ghosting will not be caused by the power levels. This is either a issue with the stb, scart lead or TV.

[sc00bie]

Ok, we have a full picture now.

There doesn't seem to be anything wrong with your set up. All the installer needs to do is change the first two way splitter for a three way one when he installs the V+. The connect the cable you already have installed to the extra room to the new output.
No problem.

It sounds to me that your signal is just to low at the point it comes into the house and splitting it again is just too much.

Lets say the power is -12 when it comes into the house. The first splitter will cause a loss of 3.5db which will give your STB a power level of -15.5db. Most stb's will just about work ok at this level.
Then when you inserted another splitter after the first you are now providing 15.5 minus another 3.5 making only -19db going into the box which will loose channels.

Does this make sense to you?

So what needs to be done is to up the power on the way into your house by either moving your tap point in the street cab to a higher level or putting in a thicker cable.
It is also possible that there are some dodgy f-connectors on the feed coming in that is causing a big loss.

There is no real way for you to test the power of the DTV signal coming in to give us a better idea but what you can do is look at the power supplied to the modem.

go to http://192.168.100.1/ and this will take you into the modem diag screens. In here you will find (look around) for the downstream power level.
The modem power is mostly higher than the DTV one so if yours is really low then we will have a good idea of the problem.


The ghosting will not be caused by the power levels. This is either a issue with the stb, scart lead or TV.

Make perfect sense to me thanx. BTW I'm no TV engineer but my old man was a spark to trade so have learned a few things from him especially when it come to proper wiring and connections :shocked:

Ok, checked the cable modem for the signal.

Downstream is:
sig to noise is 37db
Power Level is 9 dBmV

Upstream power level: 43 dBmV

We occaisionally loose the telephone when there has been heavy rain or an engineer in doing work for someone else in the street. 9/10 they have put some sort of connection unit back upside down and well water and electrical connections are not sympathetic to each other espescially when the unit fills with rain water! So it wouldn't surprise me if the connections, if in the same point are grotty. I also know the 'card' for the cable modem in the street box has been replaced on at least 2 occaisions.
When I had the whole thing installed all those years ago I complained because the picture quality was poor. After several tech had been to investigate they could not tell me what was causing it, I went round all the connections they had done to find the wall socket plate they put in to have the screening wire partially trapped in the signal clamp. making a fresh connection resolved this, but did not impress me in the least with the workmanship.
Anyways thats an aside so be sure the connections are good internally at least.
Thanx again.

[Jonnymeg]

The modem power is fine...in fact it is very high but this does not mean the DTV signal is.
We are none the wiser.

Have you tried leaving the box in its normal position and connecting the splitter up? Do you loose the channels regardless of what room the box is in. You should try this to rule out the cable running to the second room.

Have you tried
I think the only thing you can do is wait for the installer and his meter.

Let us know what happens.

[Graham M]

Sometimes a high signal can be as bad as a low signal and require an attenuator mind you

[Jonnymeg]

Sometimes a high signal can be as bad as a low signal and require an attenuator mind you

Quite correct but on this occassion that seems unlikely as the problems only occur once a splitter (attenuation) has been placed in the loop.

[sc00bie]

Ok,
I have a 1 in 4 out passive splitter (this is the same type used just with the extra 2 outlets no 3.5db or anything). if I put this in position and connect up the current cable, the one to the kids room + the modem connection i.e 1 signal to 3 outputs, keeping the std 0.4db isolating outlets on the original cables, I loose the discovery channels.

I find each time I do something the STB takes a complete flaky, when it boots up. As it stands I have resorted back to the 1 to 2 split and it has taken several attempts to get the STB to display the lost channels, adding to the problems these channels are now stuttering and clicking. I even had trouble at one point getting the std BBC1 to display. Error on screen was this channel cannot be displayed or I have not subscribed to the channel !
Last time I waited a good 30 mins before connecting the STB back up.

I kinda think it will be best to wait till the install. 17th is confirmed.

I appreciate all the replies and clarification provided esp jonnymegs willingness to try and get to the root of the problem, it's frustrating that more probs are arrising as we progress. I just don't want to make things any worse !

I'll be sure to post back to let you know what happened.
Many thanks - scoobie

[Graham M]

There's no such thing as a Passive Splitter that doesn't lose any signal when it splits

[Jonnymeg]

Ok,
I have a 1 in 4 out passive splitter (this is the same type used just with the extra 2 outlets no 3.5db or anything). if I put this in position and connect up the current cable, the one to the kids room + the modem connection i.e 1 signal to 3 outputs, keeping the std 0.4db isolating outlets on the original cables, I loose the discovery channels.

I find each time I do something the STB takes a complete flaky, when it boots up. As it stands I have resorted back to the 1 to 2 split and it has taken several attempts to get the STB to display the lost channels, adding to the problems these channels are now stuttering and clicking. I even had trouble at one point getting the std BBC1 to display. Error on screen was this channel cannot be displayed or I have not subscribed to the channel !
Last time I waited a good 30 mins before connecting the STB back up.

I kinda think it will be best to wait till the install. 17th is confirmed.

I appreciate all the replies and clarification provided esp jonnymegs willingness to try and get to the root of the problem, it's frustrating that more probs are arrising as we progress. I just don't want to make things any worse !

I'll be sure to post back to let you know what happened.
Many thanks - scoobie

As zeph says all splitter cause a loss. a 4-way one will give you a drop of around 9db.
Put the two way back in and connect up your modem to one point as normal and then use the other to the kids bedroom. Place the STB in the kids bedroom and see if it works.
If it does you have a signal problem for sure and the only way to solve it will be to add power to the incoming feed or to use a HDU.
A HDU is a big splitter with 4 outputs but the difference is that it is powered by the mains. These HDU's split the signal without causing a loss in power.

[sc00bie]

ok, moved STB to kids room and connected as req.
Connected the cable to 2nd output on splitter for kids room, put the 0.4db isolator on to this cable.
Booted the cable box.
Got all channels although stuttering on the discovery ones some others noted as well.

Have moved everything back to as was and have all channels in liv room again, but stuttering continues.

So would suggest the cable to the living room has no issues, and down to the signal from VM?

Sounds like either the guy boosts the signal from the outside box in the street or a HDU for the incoming signal....

[Jonnymeg]

ok, moved STB to kids room and connected as req.
Connected the cable to 2nd output on splitter for kids room, put the 0.4db isolator on to this cable.
Booted the cable box.
Got all channels although stuttering on the discovery ones some others noted as well.

Have moved everything back to as was and have all channels in liv room again, but stuttering continues.

So would suggest the cable to the living room has no issues, and down to the signal from VM?

Sounds like either the guy boosts the signal from the outside box in the street or a HDU for the incoming signal....

Yep... That is defo your issue.

[sc00bie]

Big Thanx jonnymeg :nworthy: really appreciated. must be owe you a few :beer: by now.
sc00bie ;)

[sc00bie]

Hi Guy's, V box delivered and installed today.

Well after all our discussion and finding out that the signal was most likely to be the culprit the engineer arrived, called me at work to ask where the cable to the kids room was.
'Well it's in the attic marked bedroom, lying disconnected waiting for you to connect' location etc.
So he has promptly put everything onto the 4 way splitter (which I had left screwed to the joist) that got disconnected for the reasons of missing channels, set everything up and bye...
(The misses didn't make sure that all was working, my fault as I forgot to ask her :dunce: )

Well guess what the guy didn't do?
yep, didn't check the signal, so we now have 2 STB's with missing channels!

Nothing like a half assed job, can't say I'm at all impressed and not good for CRM.
So I've now got to have time off for someone to come fix again.

So I thought I'd just give an update to confirm even more that the signal is most definately the issue.
Cheers Sc00bie.

[Jonnymeg]

Hi Guy's, V box delivered and installed today.

Well after all our discussion and finding out that the signal was most likely to be the culprit the engineer arrived, called me at work to ask where the cable to the kids room was.
'Well it's in the attic marked bedroom, lying disconnected waiting for you to connect' location etc.
So he has promptly put everything onto the 4 way splitter (which I had left screwed to the joist) that got disconnected for the reasons of missing channels, set everything up and bye...
(The misses didn't make sure that all was working, my fault as I forgot to ask her :dunce: )

Well guess what the guy didn't do?
yep, didn't check the signal, so we now have 2 STB's with missing channels!

Nothing like a half assed job, can't say I'm at all impressed and not good for CRM.
So I've now got to have time off for someone to come fix again.

So I thought I'd just give an update to confirm even more that the signal is most definately the issue.
Cheers Sc00bie.

Moral of the story....... get a new wife!

I always make sure i am home for things like this....you can't trust women!

[sc00bie]

Nice one! :D
Well she got :redcard: and sacked on the spot, after all we had talked about everything that was tried up in the attic etc, incl disruption to her watching tv.

och well, what would life be like if it were perfect all the time.
Here's to monday's call out !

[PS1]

HDU's do not boost the signals they only maintain the currentl level without the need for splitters.

thats what i said?

[Jonnymeg]

what happened to end this story? was it fixed?

[sc00bie]

Hi Jonnymeg,

been busy with work.
So tech came out and has done something in the attic (yet to investigate what), said they'd monitor the signal for 24 hrs, but the picture is stuttering and speach drops, blocky picture etc. Comes through on recorded material too, so at least I can give an example for the tech
Today my better half txt me to say the V box wasn't giving any channels, Got home, turned it off, took the card out, gave it a min, back on and got channels back, The kids room seemed to be fine, although issues with sound and picture.
Looks like I'll need to get tech back out. Once I get up to the attic will let you know if there is anything added / changed.

Oh and six weeks - still waiting for the upgraded modem for broadband, called them 3 weeks backto find out where it had got to, we have a backlog it will be with you asap, I've escalated to my Supervisor! yawn...

Thanx for prompting me... sc00bie

[digitalspace]

Any update on this? Love little stories and such ;)