The connector for the Now TV box is a male coax plug (that's the part that goes on to the end of your cable). The socket on the Now TV box itself is a female coax. Male goes in to female. Generally we'd use a male TV coaxial plug like this
LINK fitted directly to the cable. You can find "how to" videos on Youtube for fitting.
As to the question about what you can reuse from the parts you have, that depends on how you intend to wire up.
The Now TV box doesn't have a aerial loop through. This is a female connection socket for the incoming signal along with a male connection socket so that the aerial cable can connect to a TV set of other downstream device. You'd wire this way if the TV was to be used standalone on Freeview as well as for watching the Now TV streamed content.
Since the Now TV box has only an RF input, then getting the Freeview signal to the main TV as well would require some kind of splitter. The aerial feed goes in to the splitter then feeds out to the the Now TV box and to the TV. This is subject to the aerial's signal being of good enough quality and sufficient strength to stand being split, of course.
Splitting would require some parts:
1:2 RF Splitter
LINK This particular type uses the screw-on satellite-type F connections, so there's a chance you could make use of your F-to-F lead and fit the F to Coax plug on the end to make it a flylead from the splitter to the TV or Now TV box.
That leaves you needing a connection from the aerial down lead to the splitter (an
F plug), and another F-to-coax fly lead for either the TV or Now TV box that isn't yet connected. For the last personally I'd use a length of the same coax as the downlead and fit an F plug on one end and a male coax on the other.
Don't buy crap cable.
The internet is awash with cheap low grade coax. Buying and using it is a false economy. The outer jacket doesn't last as well against the UV in sunlight and it becomes more brittle in cold weather. When it cracks and water gets in it eats the aluminium braiding causing a break in the conduction of the cable and so a loss of signal. If you've had a chip or nick in the varnish on alloy wheels then you'll have seen first-hand how aluminium reacts to the presence of water and air. Cheap coax does the same, only faster. This doesn't happen with better grade coax using all-copper foil shielding and copper braid.
The other issue with cheap coax is that the core is made from steel with a thin anodised layer of copper for appearance-sake. Steel is not such a good conductor as copper, so besides corrosion concerns you also have higher resistance because of the grade of materials and generally poorer construction of the cheaper coax. In short, less signal at the TV.
Labgear PF100 is under £6 for a 25m drum. It is the equivalent of 23p per metre. It's an all-copper construction RG6-sized cable, perfect for your needs and decent quality. Buy it.
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