If it's working (even if it needs a Freeview box to be able to actually use it) BHF will collect it for free, so that they can sell it in one of their 'Furniture & Electrical' shops:
https://www.bhf.org.uk/shop/donating-goods/f-and-e-collection
If it's not working, Portsmouth City Council will charge a whopping £30 to collect it. (Ideally, it would be better to find someone - such as an unemployed neighbour who needs a bit of cash - to take it to the recycling centre for perhaps half that sum).