SAT flush-mounted box: Modem does not work. Frequency filter?

Hello.

We have purchased a SAT flush-mounted box[1]. The coaxial cable comes from the basement one floor up, then into this box, where the cable modem is plugged in from the outside. If we connect the cable from the basement by hand to the cable for the modem, it works. However, it does not work when we use the box. We tested 2 boxes and it does not work. Could it be that there is a frequency filter inside and only TV frequencies pass through, but not the spectrum required for the cable modem?!? If so, what kind of box would we need?

Thank you very much!

First: Are you sure that you have plugged the cable into the correct port?
Second: The cable network is a very wide-meshed network (your neighbors are also connected to it) and therefore must be well configured so that everyone gets sufficient signal strength. For this purpose, there are attenuations in the cable sockets (both for the connection and for the forwarding). These can be calculated, but you must not just insert any socket in between. If the neighbor no longer receives a signal because you installed an additional socket, there will be trouble. Therefore, most cable providers prohibit the independent installation of end sockets. Get a professional for this; otherwise, it probably won't work.

It is a single-family house, so there are actually no neighbors who could be disturbed. In my opinion, we have already used the correct connections - actually, you can't really do much wrong... or can you?

Who configured the cable connection at your place? Normally, the cable network operator comes out. When I look at our connection, I have my doubts about how a layperson would connect the right cable to the right socket – there is a lot to choose from.

The modem was previously in the basement. So we simply replaced the cable that used to go into the modem in the basement with a 12-meter long cable and led it one floor higher.

This way, the modem still works on the upper floor. However, since it doesn’t look very nice when the cable just comes out of the wall there, it should be neatly connected through a socket. So the correct signal definitely goes into the socket, but just doesn’t come out again.

That really sounds to me like an unsuitable frequency filter in the box, but you should take the hints above seriously. Neighbors in neighboring houses on the street can also be affected. Why does the modem have to go upstairs? Can't you distribute the network?