Just finished digging out the rotten fence post broken a couple of months ago...
A bit of an ordeal, seemed to be buried about 6 feet down. Chiselling the concrete was very slow, so got the SDS out. Even then, had issues with the wider head chisel bits getting stuck due to the broken bits backfilling behind the head, so had to rescue the wide bit with the straight shank bit. Eventually, decided not going too deep was the answer, just continually breaking it up, remove the bits and repeat (x100).
Eventually, I was able to wack the broken bit back and forth enough to loosen it for removal. I'm knackered now
Trip to the woodyard in the next village beckons. Might leave it to next weekend. I need one post, 2 six foot panels (one for the front at the side, which slots into a concrete post, so that will be easy), and one for the back with new post, and some bits to make up a 3 foot end piece.