Hi Bob,
The symptoms point to the 'beamforming' feature, which is often incompatible with iPhones and Android devices. Simply disable it under Wireless - Professional - for the two bands 2.4 GHz and 5 GHz (both settings: Explicit beamforming/802.11ac Beamforming and Universal Beamforming).
Reboot the router and 'forget' (=remove) the WLAN settings on your devices and re-connect fresh.
Joe and others,
Thanks for taking the time to reply and offering feedback. I really appreciate the help and know how difficult it can be to diagnose something as complicated as a networking environment with so many variables
Just so the issue is clear - The original main problem is an ongoing sporadic wireless connection of AC66U to Laptop. Although use of iPad, cellphone, other devices is important, I added info on the stability of their connection to router testing primarily to determine if the PC was as fault. Since they also show connection drops, I can reasonably conclude that PC NIC etc is OK.
And using the PC via Ethernet cable direct to router where connections also drop suggest that it's not simply or solely a wireless issue. This conclusion is less clear since the wired drops are much less frequent.
As for "beamforming" settings as the possible cause. I think this illustrates part of the problem with resolving various performance issues - My AC66U v378.54_2 "Wireless -> Professional" settings page offers 20 some options, none of them contain the word "beamforming" and most have very limited superficial info on what they actually do/control. The point here is, although the AC66U may a great router with terrific Merlin firmware, it's difficult to use/setup effectively when meaningful documentation for so many config options is lacking.
For instance on Settings - On the basic "Wireless -> General" page, I'm not even entirely sure what is the proper "Channel Bandwidth" setting and why. Anyhow, as I mentioned above, I'll solve the iPad and Android issues once PC problems are solved and understood.
I routinely survey the bands in my relatively crowded neighborhood. Usually all channels are equally busy and I typically leave the router "Control Channel = Auto" for both bands. This setting has been maintained consistently through other firmware releases that seemed stable. Again, not exactly sure how any of the settings should be configured but try to stay consistent across firmware installs.
At one point, inSSIDer utility data suggested that perhaps my Chromecast was the culprit but have eliminated that possibility by removing device from the network and connection drop problems continue.
The AC66U is not overclocked.
I am the original June poster and the current testing focus returns to temperature. Yesterday, I took the time to remove AC66U cover and check what I could on circuit board for heat sink seating, other loose connections, dust etc. Also bought a fan. Today I'll use the PC wirelessly connected to cover-less router cooled by fan and record performance/temps.
Quick first temps look -
- AC66U with cover about 140 degrees F for both bands.
- Without cover - 120 F.
- Without cover and fan - approx 110 F.
- (Outside temps yesterday almost 90 F and PC office around 80 F)
Bob