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

In article , JoeJoe writes

Plugs (F-type) (10pk):

The plugs are basically strip, fold back braid and twist on, sounds rough but they are secure if sized correctly. Just buy some and try it, post back if you have trouble, the connection should survive quite a tug if made correctly. The coax (solid) core forms the connector pin.

Suck it and see as is and post back if you think you need a booster.

Ask at uk.rec.digital-tv if you get no responses here or want more details than this.

Sounds like you need a passive TV splitter - most seem to go for those either connecting directly to the cable or using F-connectors instead of the Belling plugs (the type that plugs into the TV). They have components inside to stop reflections etc and are NOT the same as splicing the cables in a simple Y (despite what many cowboys seem to think). TV cable is also supposed to be weather proof so no issues there.

Also, if you need a boost, boost as close to the aerial as possible otherwise you're also boosting any noise which has crept in along the cable.

Paul DS.

A way that works to extend cables without TOO much impedance change is to strip them back and get the outer sheaths out of the way and lap solder the smallest amount of the inners you can get away with together and, if you are careful, push the insulation over that joint so the dielectric is more or less continuous, then tape that up with a bit of PVC tape and connect the outers in some way. Brass shim or tinplate cut from a mustard tin wrapped round the cable (or tube slid over it) will preserve the outer continuity and geometry. Solder the braids to that.

Then wrap the lot in self amalgamating tape.

Its probably no worse than a custom connector, electrically, and is more proof against environmentally induced deterioration.

Thanks, but I'll continue to use two plugs and a barrel if you don't mind.

In message , Graham. writes

Use a male/female connection - that cuts out one joint.

As I said. the above is probably better electrically, costs less and is less liable to corrosion.

But no one is forcing you to do it.

Or to crimp mains cables instead of using junction boxes.

Generally good advice except for sealing. The best way of making the joints weatherproof is to use self amalgamating tape. Properly applied it will last for at least twenty years. You can get the tape from Screwfix product code

Peter Crosland

Thanks a lot for that - just the answer I was hoping for as I already have the f-type fittings from another job...

Just out of interest - what does "power pass to all ports" mean?

Also, is there any interference issue with running the coax cable alongside CAT5e cables? I am only talking about 2m or so.

Buy a plastic box from CPC and put the amp in that. That's what we do.

Bill

But look at this:

Masthead aerial amplifiers etc require power to operate. Usually the power supply for these is kept in the house, and the power is fed up the co-ax to the masthead amp. Hence if you have something like this being powered from the co-ax, anything you place in the co-ax along the way must also pass the power through. Some splitters only do so on one particular port - hence in those cases you need to take care to put the outgoing lead with the PSU on it, on the right socket of the splitter.

Ones with power pass on all ports does not have this restriction.

Not usually any problem.

In article , Peter Crosland writes

Read again . . . .

There is no scale reference in that diagram. I was wondering if that is how they join high power RF transmission lines the size of tree trunks.

Do you mean the Belling-Lee ones?

I have never liked the female ones because the inner only goes in about 3mm and can easily shrink back that amount. Soldering them is not practical.

But may incorporate diodes so DC doesn't pass from port to port. But that stops you using the splitter 'backwards' with LP.

Bill

Horrid things. Use a plug and a line conn.

Bill

In article , Graham. scribeth thus

No they use connectors, large ones, and there're bolted together!...

Thanks again.

Funny you should say that, but I wondered to myself if they various ports are isolated from each other as I typed that ;-)