Extending and/or splitting coax cable - what's the correct way?

[The Natural Philosopher]

It works at any scale it is practical to make the joint.

[fred]

Snap!

Screwfix used to do the single power port version (Labgear WBS2F) at silly cheap prices so I got my few examples there. Current offering appears to be Labgear FBS402, note the directional power feed arrows on case pic suggesting diodes as per Bill's post (Ta).

For comedy effect it appears that the current version of WBS2F has the power port on the right whereas mine have it on the left. Nothing like continuity of design eh?

[Bill Wright]

A while back we needed some that would pass 24VDC from one port to the 'input' and the other port. It was easy to short out the diodes. This was with some CPC ones designed for satellite IF.

Bill

[JoeJoe]

Spent an hour under the house today and connected everything:

Cable from aerial (on roof) to splitter - around 15-20m - as before adding the splitter.

- SF didn't have the one you suggested, so I bought this one instead -

Connected TV that was originally connected to the aerial cable to splitter - signal dropped from 100% to 99%.

- Connected second TV to splitter - cable around 10-15m. Signal only

9%... :-(. Amazingly all the channels seem to work OK, including the TV guide. Only BBC channels are pixelated and unwatchable (and show 7%).

Any idea how to improve before I go down the amplification route?

PS: Used F-type plugs, wall plates, and good quality cable, so don't think there is a problem there?

[Bill Wright]

No, that sort of pratting about is a waste of time. Signal levels are generally too low. But a one input one output mains powered amp, gain around 12dB, fit it on the aerial feed, as close to the aerial as possible, but right next to the splitter if that's the best you can do.

Blake Proception PROAMP 11 is ideal.

still, if you can get to the aerial fit a 16dB masthead amp. Proception, Vision, Labgear, Antiference.

Bill

[JoeJoe]

Very difficult to reach the aerial - 15m high on gable end on a hill side...

It is also going to be difficult to provide power near the bottom of the aerial.

Is there any point in amplifying the signal just before the cable is connected to the far-away TV?

[Bill Wright]

Not really. A marginal improvement might, at best, be obtained. It certainly doesn't address the problem. If you can get power to the splitter position put the mains powered amp just before the splitter.

If not, use a masthead amp with a separate mains power unit. The 12V DC goes up the coax. The problem is that the amp still needs to be before the splitter (this is vital), but the splitter might not pass the DC power. Does the splitter have 'DC pass' written on it,

could actually use a non DC splitter and bypass it for DC by the use of two of these: it's rather a faff.

Alternatively

by a few two-way splitters on the non-powered legs to give enough outputs (split the shortest feeds).

Bill

[thirty-six]

Not usually, but might be worth a go if you have low noise levels.

[fred]

In article , JoeJoe writes

ways on the splitter, irrespective of the number of loads connected. Thus a 6 way splitter will reduce signal power to 17% vs the 50% avail on the proposed 2W splitter.

That sounds ok.

Something is wrong here, 15m of cable is not that great a loss so I wouldn't expect it to go over the edge from 99% to duff with just that. Check for stray hairs of braid that might be shorting the signal (no it doesn't always result in no signal).

If you don't need all those ways off the splitter then find a 2W splitter of the same quality (F-conns, soldered cab construction eg. Labgear) as the signal will be 3 times stronger from that alone

If you need lots of splits then you will need a distribution amp.

If you have spare cable, make up a long fly lead to temporarily replace your long installed section to see if it works ok. Was it really good cable (copper foil and braid screening)? No kinks in the cable (easily done in a back box)?

If you find you need an amp (after trying the 2W splitter alone and a replacement cable) then those suggested by Bill will be good as this is his expert topic.