I realise I should have said "been learnt since leaving formal education" rather than "happened since". As in, they taught little of real use at school for me but I learnt pretty much everything useful since leaving school.

I had a quick look at your home link and spotted the instructions to set a DGN2200 as an access point. I have an old HomeHub4 and thought I will have a go. There is no mention of the SSID or password so I imagine you recommend keeping the original. However, I did a bit of a search and found most blogs recommended using the SSID and password from the main router.
It works a treat, BUT, every now and then it freezes. My iPad shows that I have a full signal but it will not connect. Sometimes it will after a minute or so, other times I have to switch off Wi-Fi then re-connect. I suspect that the iPad is switching between routers, even though the main router has a reasonable signal in the room that has the access router. If I set a different SSID to my HomeHub5 I imagine there will be the same sort of problem when I move about the house. 5Ghz is switched off on both routers indecently as it has always been a problem in the past
Your comments would be appreciated.

In theory the same SSID should be fine, but I've found having both different is useful, so I can force a device if in an area where networks overlap to use just the one I want.

In reply to a post by MrSaffron:

In theory the same SSID should be fine, but I've found having both different is useful, so I can force a device if in an area where networks overlap to use just the one I want.

I might give that a try.
Meanwhile I've got the HH4 next to the tele. I've put insulation tape over the flashing yellow LED that comes on when the DCHP is switched off as it is distracting when watching the box but I am not sure if it would be OK to cover the main LED as I don't know where the transmitter is and don't want to reduce the signal. Anyone know?

Plastic insulation tape should make noticeable difference and antenna are larger than an LED usually, so cut down tape slightly and even if you have Wi-Fi blocking tape it should be a non-issue.