Question Will this multi-switch setup work?

Eye of Harmony

Novice Member
I have a friend who has asked me to help with a TV installation problem. I think I know what to do, but before I incite him to spend money, I wanted to pose some (easy) questions here, and to check my solution is workable.

Current Setup:
In a terrace of three houses, house 1 (H1) is the owners home, and houses 2 and 3 (H3 and H3) are holiday lets. There’s an 80cm satellite dish with a quad lnb up and running. Two outputs from the lnb go directly to H1 powering a Humax Foxsat. The other two go to H2 and H3 via the loft space, and run Humax boxes in each of those houses. There's no Sky Q, or indeed any Sky at all, it's all Freesat.
CTV-Current.jpg

Requirement:
We need to add a terrestrial feed into the H2 and H3 holiday lets. There is a TV aerial on the roof, not connected to anything yet. There’s only one cable (running from the existing quad lnb) into each building, and crucially, no possibility of adding extra coax into those buildings.

Solution:
Assuming the TV aerial works, I reckon a multi-switch in the loft and diplex outlets in the houses is the (only?) way to go. I’ve previously used an Antiference iSys 7 in my own home, but it’s expensive and overkill. This looks like a cheaper alternative (and it’s available at Amazon).

My first thought (solution 1) was to disconnect all the existing cables from the lnb, pull the H1 and H2 coax back to the loft, and run four new cables from the lnb to the loft. Put the multi-switch in the loft, connect H1 and H2, and run a couple of new cables back outside to the satellite dish and connect them to the old H1 cables. However, this would mean connecting coax cables together (bad) outside (very bad).
CTV-Proposed-1.jpg

To get round that, given that the owners don’t necessarily need a terrestrial signal in H1, my second thought (solution 2) was to swap the existing lnb for an octo lnb, run four outputs to the switch in the loft, and connect the two H1 cables to two more outputs.
CTV-Proposed-2.jpg

Questions:
- Is it okay to use an octo lnb and leave two outputs unused? Do they need terminating resistors?
- Would a cheap regular octo lnb like this one work?
- Has anyone used that Goobay switch? I know Triax seems to be well spoken of here, but the equivalent Triax multi-switch looks to be about double the price. Any other recommendations?
- If terrestrial TV ends up being required in H1, is there a recommended way to connect two coax cables together (outdoors!), or is that just a no-go?
- Have I missed anything else?

I don’t post on here very often, but this forum has always been an invaluable source of information and inspiration. Thanks in advance!
 

grahamlthompson

Distinguished Member
I have a friend who has asked me to help with a TV installation problem. I think I know what to do, but before I incite him to spend money, I wanted to pose some (easy) questions here, and to check my solution is workable.

Current Setup:
In a terrace of three houses, house 1 (H1) is the owners home, and houses 2 and 3 (H3 and H3) are holiday lets. There’s an 80cm satellite dish with a quad lnb up and running. Two outputs from the lnb go directly to H1 powering a Humax Foxsat. The other two go to H2 and H3 via the loft space, and run Humax boxes in each of those houses. There's no Sky Q, or indeed any Sky at all, it's all Freesat.
View attachment 1146175
Requirement:
We need to add a terrestrial feed into the H2 and H3 holiday lets. There is a TV aerial on the roof, not connected to anything yet. There’s only one cable (running from the existing quad lnb) into each building, and crucially, no possibility of adding extra coax into those buildings.

Solution:
Assuming the TV aerial works, I reckon a multi-switch in the loft and diplex outlets in the houses is the (only?) way to go. I’ve previously used an Antiference iSys 7 in my own home, but it’s expensive and overkill. This looks like a cheaper alternative (and it’s available at Amazon).

My first thought (solution 1) was to disconnect all the existing cables from the lnb, pull the H1 and H2 coax back to the loft, and run four new cables from the lnb to the loft. Put the multi-switch in the loft, connect H1 and H2, and run a couple of new cables back outside to the satellite dish and connect them to the old H1 cables. However, this would mean connecting coax cables together (bad) outside (very bad).
View attachment 1146176
To get round that, given that the owners don’t necessarily need a terrestrial signal in H1, my second thought (solution 2) was to swap the existing lnb for an octo lnb, run four outputs to the switch in the loft, and connect the two H1 cables to two more outputs.
View attachment 1146177
Questions:
- Is it okay to use an octo lnb and leave two outputs unused? Do they need terminating resistors?
- Would a cheap regular octo lnb like this one work?
- Has anyone used that Goobay switch? I know Triax seems to be well spoken of here, but the equivalent Triax multi-switch looks to be about double the price. Any other recommendations?
- If terrestrial TV ends up being required in H1, is there a recommended way to connect two coax cables together (outdoors!), or is that just a no-go?
- Have I missed anything else?

I don’t post on here very often, but this forum has always been an invaluable source of information and inspiration. Thanks in advance!


No need to terminate unused lnb outputs.

Not sure why you need a multiswitch with a octo lnb. Given a decent signal just connect the aerial to a UHF 1 in 2 out splitter. Use a pair of UHF./Satellite combiners to combine feed to H2 and one reversed in H2 to split them out again. Use a second pair to feed H3.

https://www.amazon.co.uk/Way-TV-Satellite-Combiner-Splitter/dp/B06Y3MR4CC/ref=sr_1_2_sspa?crid=16RR5NHSS7GX4&keywords=tv+and+satellite+combiner&qid=1556809783&s=gateway&sprefix=satellite/TV+combiner,aps,153&sr=8-2-spons&psc=1

Which Humax boxes are you going to use for H2 and H3 ?

Humax twin tuner Freesat+ pvrs can feed both tuners using a single cable with some recording restrictions.
 

Eye of Harmony

Novice Member
Oh wow, this is why I love coming to this forum. I had no idea that kind of splitter existed! Cheap and cheerful, no need to run power into the loft, and no need to change the wall plates! Thank you, that is awesome.

Not sure which Humax boxes they are, but I don't think they are worried about recording in H2&3.
 

stevelup

Distinguished Member
Are all three properties supplied from the same electrical supply? Are they on the same phase?

There's an element of risk if not...
 

grahamlthompson

Distinguished Member
Are all three properties supplied from the same electrical supply? Are they on the same phase?

There's an element of risk if not...

Just needs a screen earth bond on the 8 outputs of the lnb if they are on different phases. No issue with the purely passive terrestrial feeds.
 

Eye of Harmony

Novice Member
Same electrical supply, yes. Same phase, doubtful. It's a three phase supply and I haven't looked into how the electrician split the phases. The passive combiners look like the way to go though. Is it worth earthing the existing quad lnb outputs then? I don't think that's been done by whoever installed the original dish.
 

Rodders53

Distinguished Member
Wallplates will need diplexer with UHF and sat outputs. As the TV-sat combiner.
These DO lose signal on both UHF & TV paths (according to Labgear and Triax specs).

May make marginal signals impossible. Even with only two fed (passive UHF splitter -4dB, diplex in & out maybe another -5 or 6 dB? so 9dB down (1/8 the input level.)

Exact brands of kit and specs may need poring over and LOCATION as always is key to likely signal levels. Using something like Wolfbane and the digitaluk predictors if in the UK. Then do the gain / loss calculations to be sure it will work.

Local wiring regulations may dictate needs for earth bonding wherever this is. But - whole not required in UK for a single dwelling - it's not 'bad practice' to do so. F-socket earth bars are readily available.
 

Eye of Harmony

Novice Member
Good point. I should have mentioned the property is in central France. We get a pretty good satellite signal here with an 80cm dish (I've never had any loss of UK channels except in the heaviest of rain - happened maybe twice in the last 15 years).

For the terrestrial signal, we're about 3 miles from the transmitter, but there's a hill between us and it, so it's not exactly line of sight. I get a decent signal with an aerial in the loft though, so hopefully with a roof mounted aerial my friends will have a strong enough signal for this to work.

I think my next step is obviously to go and check the signal levels at my friend's property.

If signal is marginal, will a multiswitch cut down the losses?

Thanks for all the feedback, really appreciated.
 

Rodders53

Distinguished Member
I think my next step is obviously to go and check the signal levels at my friend's property.

If signal is marginal, will a multiswitch cut down the losses?
Good idea. Ideally with a pro meter or a few fixed attenuators to reduce the current levels to what might be expected with the diplexers inserted?

Multiswitches should correct but most are aimed at larger installs than you are planning

https://cpc.farnell.com/optima/121420/multiswitch-5x8-lte-optima/dp/AP02652
and
https://cpc.farnell.com/triax/318109/tms-508-se-aq-bs-5x8-quad-multiswitch/dp/AP03341
would both seem to offer a minimal gain or loss option (remembering the diplex wall plates add a 2-3dB loss still).

Other more expensive switches may permit more active gain/loss control. But a bigger dish could also provide that on the sat side and UHF aerial amplification is relatively simple.

Caveat: my main knowledge experience is not in this sat multiswitch field, so I'm working from my terrestrial distribution knowledge and extrapolating from the specs and background reading.

EDIT I suspect for two rooms the passive route and basic multiswitch will be very similar in gain/loss. Do the sums to check. But you may or may not need more signal from the TV aerial side.
 

winston2010

Well-known Member
Are all three properties supplied from the same electrical supply? Are they on the same phase?

There's an element of risk if not...

Also a bit concerned about your loft. Is it just one open space above all three houses? It ought to be divided into three to provide a fire break.
 

Eye of Harmony

Novice Member
There are two lofts I think (it's not my house). One over the owners house, and one over H2 & H3 which were originally one house but subsequently subdivided to make the two lets.
 

Eye of Harmony

Novice Member
Just wanted to update this thread to say that I went with the suggested solution of an aerial splitter into a couple of passive signal combiners and it worked a treat.

In one house I swapped out the wall plate for a new one that split the signal, and in the other I just used another combiner in reverse (there was a composite set of sockets and the splitter module costs a flipping fortune). Everything works great and the TVs report 92% signal strength.

Thanks again for all the replies and suggestions!
 

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