Problem is TC and related to execution of backups
Hi everyone... I've been dealing with this issues for years now including at least 3 home networks that I manage (including my own) with all sort of wireless and wired setups including several models of Airports Xtreme, Xpress, TC, Apple TV, MacBook, iMac and not Apple devices (Android TV, PC, etc).
I've used a lot of different AWESOME networks apps (both for Mac and PC) that allows me to monitor signal strengths, interferences, bands, what computer is connected to what devices using X or Y bands, etc......
(that was just an intro so that you can trust I've verified almost all thinkable scenarios) and have come down to the following conclusion: the disconnection symptom is related to the execution of backups in your TC.
If anyone here is interested on reading more of how I got to that conclusion I'll be happy to share more but bottom line is that when you lost internet (and it seem like the TC drop you off) "technically" your wireless card is still hook up to the time capsule (so technically you are not disconnected although your signal indicator in your computer might show that you are "disconnected" is just that the time capsule is no longer serving internet to your computer.
Got it? It may not make much sense to start with but what I am saying is that you indeed do not have internet in your computer and your signal strength indicator might or might not show that you are disconnected but for your time capsule you are still connected is just that some how it get's so busy doing something with the backup functionality that it just doesn't serve internet to your devices for certain period of time (10 mins maybe?) until it gets available again, at that point it start serving internet again to your computer and all get back to normal.
I'll research a bit more on this direction, although my final solution is not to use TC for providing internet to my other devices and keep it just doing backups (which of course implies purchasing of additional Xtreme or Xpress for taking care of the internet) I might come back to this here with more info from my research in case someone is interested on reading more of this.