The Internet does not have a signal. Your WiFi has a signal. The Internet and your WiFi are very different things as far as trying to troubleshoot a problem. Is it your WiFi that you are having problems with? If so you need to provide more information about
I have had Internet 75 over copper for some time now. It uses a bonded modem which requires two copper feeds to the modem. When it was first installed there were issues with it. The service tech did quite a bit of investigation and told me that one of the copper feeds had a "tap" on it that was causing the signal to be "weakened". I gather a tap must have been an unplanned connection to one of my lines. I said he removed it and the signal strength improved.
More recently when I acquired an iPhone, which was connecting using WiFi, it would not stay connected to WiFi for more than a hour or so. I was continually having to turn the phone off and back on again, or turning the WiFi on the phone off and back on again (airplane mode). After a lot of investigation and some help from this forum I discovered that my iPhone did not like the 5 Ghz WiFi connection. I forced it to use the 2.4 GHz signal and all problems have been solved.
If this sounds like your problem I can provide more detail. But as has been suggested by @xray , you need to figure out if it is the whole modem service or just the WiFi that is a problem. A modem or feed problem will affect both the WiFi and Ethernet connected devices.
If the issue is limited to wifi, then it's possible that you're getting interference from another nearby wifi device using the same channel. If you're comfortable with it, you can login to the modem's control panel and change the device channel to see if that helps. If not, this is something that Telus support can easily assist you with. They may also be able to increase the wifi signal power.
@Yin1 have a look at this thread. The Internet 75 uses something called Smart Steering. It switches your WiFi back and forth between 2.4 and 5 GHz. You can turn it off and create a new SSID for the 2.4 Ghz band. Then you have two options for signing in WiFi devices. This will allow you to assign different devices to each band. If everything still goes down at random then that suggests a hardware problem with the modem or wiring to the house.
I had the same problem and I finally figure out how to fix it. Thanks for friendly guys online. It happens to be the IPv6 issue. First, you can login the telus ip address 192.168.1.254 with admin and password. Then go to advanced settings, click on proceed on the warning message. You will see the IPv6 menu on the left side. You need to disable IPv6 and click apply button. You will see a warning message "call technicians before, blabla" just click yes go apply. After the resetting done, you will see the difference. Hope this will help.