What can be a problem in the connection Provider - Router - Laptops (phones, etc)?

Question

network hardware

Hello. Such a problem.
The Internet is connected in Techniclolor CGA-2121
TP-Link WR 740N is connected to it
The problem is that WiFi periodically falls off.
It was: 2.4 + 5GHz on Technikalor + 2.4 on TPLink. Falls off, something else. With the 100 Mbps promised by the provider, it gives out 5-10 maximum.
When I cut off both networks on the main router, TpLink works and gives out 60Mbps approximately, but it cuts off on all devices once an hour. Plus or minus.
Default settings on routers.
It is chopped off on laptops (both Winda and Lin), and SmartTV, and PS4, and AndroidSmart.

Where to look?

Answer 1

the main problem is the one who did it, he does not understand what he did and how it works. WiFi is evil, especially in the hands of people who don't understand how it works.