Installation of a satellite system

To get back to the actual topic, if the OP doesn't even know what a coaxial cable is, it is not recommended that he climbs on the roof and connects the system himself, PERIOD.

Full agreement!

Install the multiswitch as close to the dish as possible (under the roof) to prevent signal loss.

Strong objection, that is wrong!

Even if most tuners still cope with non-standard low levels, the standard level window of 47 - 77 dB(µV) must be maintained at the satellite IF at the subscriber outlet. No matter how far a multiswitch is installed from the antenna, with the same total cable length the same level will always reach the subscribers.

As long as the tuner's threshold is not exceeded and there is no overload, the levels have no influence on the signal quality for digital signals anyway.

In Unicable/Jess matrices with AGC control, input levels of usually 60 to 90 dB(µV) are equalized to a constant output level. When switching from cable connection to satellite reception, especially for long LNB cables with high attenuation, it is therefore advantageous in terms of level to install the single-cable router in the basement, because then the attenuation slope of the LNB feeder lines only passes through to the legacy connections.

I didn't mean to say the higher the input level, the better. My thought was simply that a level comes from the dish or LNB, which depending on the weather can be borderline extreme. If a long cable follows, the signal is further attenuated. From there, meaning in TV technology, I'm not very familiar. However, if the multiswitch passes the signal on without processing, then the location of course doesn't play a big role. I assumed that the signal is processed here, in which case it would indeed matter. That with the digital signal, it only works or doesn't work is undisputed and clear to everyone, I think.

Signal processing is understood as the conversion of a signal to another frequency or a modulation change from DVB-S to DVB-C, OFDM, or PAL. Multiswitches switch the selected satellite layers from the LNB through only more or less attenuated.

It is undisputed and clear to everyone, I think, that with digital signals it only works or doesn't work.

Even during the time of analog satellite transmission, the following applied:

LNB input level - attenuation of LNB supply lines +/- amplification or attenuation of the MS - attenuation of star lines = subscriber level

Thus, the same distribution network attenuation results for analog reception, regardless of where the MS is installed. Also, C/N and MER at the subscriber cannot be influenced by the MS position.

Noticed too late for editing:

Instead of LNB input level, it should of course have been LNB output level.

As far as everything is correct, if I have a relatively small dish and therefore install an amplifier, then it makes the most sense to place it directly behind the dish and not only in the basement. And that is exactly what I meant, if the multiswitch should also amplify the signal, then positioning it here with short cable runs to the dish also makes sense...

A small bowl doesn't make sense - you only get annoyed and where nothing comes, nothing can be amplified.

By the way, I can recommend "powerless" multiswitches.