Interesting Wi-Fi speed event

[#1]

Just picked up on an 'interesting' effect - just this morning tested my download speed using Fast.com and, for my 150Mbps FF contract service was only giving me *very* variable speeds between ~50Mbps to ~90Mbps. Usually I test at 150Mbps.

What's going on? I think I may know... 😃

Normally: I am on a 150Mbps FF PN contract, I use a TP-Link Archer AC1300 Mini Wireless MU-MIMI USB Adaptor on a USB 3 port to connect my PC by Wi-Fi to my PN Hub 2 router, where I have the 2.4GHz Wi-Fi switched off leaving only the 5GHz Wi-Fi link operating.

Yesterday: My friend spent the afternoon at my home, before we went out in the evening. She has a slightly older smart phone contracted to '3'. She often has trouble with phone calls on her phone, certainly so at my home (as I sometimes do - I only use Wi-Fi calling now when home). I offered to put her on my network to allow her to use Wi-Fi calling when here. This I did, but had to turn the 2.4GHz Wi-Fi back on at the Hub 2 as her phone seems not to use 5GHz.

Today's Test: See above.

I looked at the USB Wi-Fi adaptor's Status for the network link. Speed: 144.5 Mbps

Aha! Its operating on 2.4GHz, that explains the above results. Let's try changing that through the driver:

Properties -- Advanced -- Property: VHT2.4G - Disabled

Network link Disable, then Enable - link re-established, after a few tries. *But, still showing link Speed: 144.5 Mbps!*

Log on to router, disable 2.4GHz Wi-Fi there. Reboot PC. Check adapter link Speed: 780 Mbps

That's more like it and, of course, my measured download speed is back to its normal and stable measured 150Mbps.

So, what's going on? Does the 2.4GHz Wi-Fi being on somehow reduce the available speed for the 5GHz Wi-Fi link on the Hub2? Or do I need to do more testing?

[#2]

VHT2.4G - Disabled ... Does this just disable the non standard "VHT" (Very High Throughput) aspect of the 2.4GHz band of the USB Wi-Fi adaptor ?

In any Dual Band Wi-Fi system is it the Wi-Fi adaptor of the user's mobile / computer / etc that selects which band to use.

[#3]

It appears that a common point of confusion for many individuals is the distinction between Wi-Fi speeds and broadband speeds, a observation I've frequently encountered in various discussions over time.

[#4]

I have tried a couple more tests, with interesting though probably inconclusive results:

Turned 2.4GHz Wi-Fi back on at my PN Hub 2, along with the usual 5GHz.
PC Wi-Fi still on 5GHz link (speed) using USB TP-Link AC1300 device

Disabled PC Wi-Fi Network USB TP-Link AC1300 device
Enabled PC Wi-Fi Network USB TP-Link AC1300 device
PC Wi-Fi Network still on 5GHz link (speed)

Turned off PC (Not just Restart), Rebooted PC (to give the USB TP-Link AC1300 device a hardware reset/reboot)
PC Wi-Fi Network still on 5GHz link (speed)

Re-Enabled VTH 2.4G flag in TP-Link device
Wi-Fi link self disconnected and then immediately reconnected, still at 5GHz (speed 867 Mpbs)
Turned off PC (Not just Restart), Rebooted PC
PC Wi-Fi Network still on 5GHz link (speed 780, 867 Mpbs)

Maybe not definitive but perhaps, if both 2.4GHz and 5GHz are on at the Hub 2, it's just by random chance which one the TP-Link Archer 1300 picks up on first? Umm... I wonder if this could be helped out if the Hub 2 had the ability to separately name the two Wi-Fi channels? It doesn't really matter in my simple situation but with many households nowadays using many Wi-Fi devices using different wavebands, along with the higher speeds brought by fibre to the premises, one can see how it could lead to issues and complaints about 'download speed'. Anyway, something to be aware of.

Likely different Wi-Wi devices behave in different ways. Here is some discussion and information around this topic I found online:

e.g. I saw this - not my USB Wi-Fi adaptor, but the same idea:

Disable 2.4Ghz on network adaptor

https://www.reddit.com/r/tmobileisp/comments/19a1km9/disable_24ghz_on_network_adaptor/

Brief introduction of Wireless Channel, Channel Width and DFS

https://www.tp-link.com/uk/support/faq/4309/

[#5]

Just an update on this:

More experience over time, running both the 2.4GHz and 5GHz Wi-Fi channels on my PN Hub 2 router with my TP AC1300 mini USB Wi-Fi adaptor in the PC, shows that the AC1300 typically does pick up the 5GHz link at boot up. However, occasionally the 2.4GHz link is the one established. This can usually be changed simply by Disabling the AC1300 adaptor and then Enabling it again via Network Connections on the PC.