Thank you so much for this, very much appreciated, despite your reservations it is very helpful. At least it means I am not banging my head on a brick wall because my phone is obsolete.
I still cant connect but your post means that I will persevere.
I have two HTC One M8's which I am hoping to use as model railway controllers. Your post that says you have good connections on even older phones means that I am recharged to find the actual problem rather than saying it must be my old phones.
Once again thank you for your interest, and to be bothered to reply.