Yes, that's the one. Another little bit of local history decaying.
There was a similar one by the public lavvies on Harborough Road opposite the big supermarkets (Sainsbury?) and one on the south west sector somewhere, I'll find out where that one was.
Edit - I'm told Harlestone Road, but that's the one bit of town I'm not familiar with so couldn't say where.
That is indeed the one. I think it is still in use,
Felixstowe - on top of the Martello tower.I'll be impressed by the first CC'er to bag a Coastwatch station.