Talk to me about coax.

[Strawberry]

I'm thinking I'd like to put a discone in the loft as I've just bought an RTL SDR V4, the coax run would need to come back down to the ground floor via a bit of a convoluted run, about 40 meters, maybe a bit more by my guess.

I don't want to use thick RG213 type cable as it's bulky, ugly and it doesn't go round tight corners well,

I've got most of a reel of 75 ohm sat cable, I was thinking about using that but, yeah 75ohm, not ideal.

I'd like advice and ideas on what would be the best 50 ohm option, about 7mm max diameter, fairly flexible and hopefully not too lossy.
Thanks
Neil

[ch25]

Use sat cable.
I use sat cable to all my rx antennas cause it's cheap and 75/50 Ohm doesn't matter in that case.
I also use 75 Ohm coax to my transmit antennas, but antenna must be monoband.
Chris

[Chanty Wrassler]

I use SAT100 or CT100 for all my receive antennas (and one or two tx ones, too), as it's good quality proper copper core and braid with extra copper sheathing. There's not a huge difference in price between the cheap and nasty basic sat cable and this stuff, so it's worth the extra, without paying much more for RG213, and the like.
For receive purposes it's ideal, with quite low loss.
Only slight embuggerance is the F-connector system isn't very reliable, so I have to fart around a little bit adapting connectors in order to get a good soldered end.

[AndyDCD]

I've used RG8-mini, which is about 7mm diameter. It's a better spec that the dreaded RG58, but still easier to handle than RG213.

With just a receiver using sat type coax shouldn't make much difference at all, but you are right about getting connectors for it.

Foil screened cables don't like being flexed though, you'd need to clip it in place.

[paulears]

Ive always smiled at how sat cable has magical specifications and is so cheap and amazing over long runs, but commercial users spend huge amounts on hardline on their receive antennas? They could have bought a reel of ct100 and solved their loss problems.

[Ant]

Remember, losses are on receive also........you'll only hear what you don't attenuate.