Repurposing internal TV wiring

[Dave2002]

But if signal strength really an issue, consider a pre-amp next to the satellite dish?

Thanks for this.

Currently there seem to be two main types of satellite cable.

Sky shotgun cable is narrow diameter, and presumably can be pushed through narrow gaps and small holes. I think it's fairly low loss, but I'm not sure how it compares with other cables.

Otherwise most of the cables are coax, with various degrees of quality. I think the air cored ones may be better, but I don't know enough about how the cables are made to be sure which are the best. Previously the cable I had from Satcure was slightly larger diameter than some other cable, and required slightly larger F connectors to connect to equipment.

Re amplifiers, satellite systems usually have an LNB - low noise block - which amplifies the signal before feeding it down the cable to the equipment right up at the dish end. Power for the LNB comes up the cable. While signal strength might be an issue, I think the main aim is to get the noise level down. Thus I don't think adding in extra amplification other than from the LNB would be a good idea - though swapping LNBs for better ones could be. Somebody might want to tell me if my hunch here is wrong. I'll probably change the LNB anyway, to an 8 way one compared with the current 4 way one.

You are now making me think though, that although keeping the optimimum SNR is important, that it (arguably?) might be less important in a digital system, thought that would depend on several factors, including how much error correction is built into the broadcast communications.

[Quarky]

I would guess a digital signal would be inherently more resistant to noise, and therefore a lower SNR may be accommodated.

All a preamp would do is amplify the incoming signal, but amplify the noise as well.

[Dave2002]

I would guess a digital signal would be inherently more resistant to noise, and therefore a lower SNR may be accommodated.

All a preamp would do is amplify the incoming signal, but amplify the noise as well.

Actually we do have to be careful when talking about a “digital” signal. It’s actually still analogue, but depending on the modulation methods used (I’d have to check) e.g. 64 PSK, COFDM would tolerate some noise - at least up to the point where the digital data stream is decoded into bits.