Strawberry jam

This morning  we went to uke class at the theatre. After a quick lunch next door  at the Arc (library cafe) I cycled on to the care home to visit one of my Mother's friends there. M has always lived in the St Cross/Winchester area and we had a good chat over tea and cake about her earlier life, and how the city has changed. She has a lovely view from her room over the water meadows and St Catherine's hill, and in the winter when the trees are bare she can see the cathedral, too. Then I tapped on the door of her neighbour, J, the retired senior police officer, who was another of my Mother's friends. They used to take breakfast together. Although not expecting me, J was pleased to see me and regaled me with more of his stories, this time tales from Totton Police station in the 1950s/60s. (Totton was a less salubrious suburb of Southampton). Although sometimes his stories are rather gruesome, J is a good raconteur and I have a lot of time for him (today a good 45 minutes !). 
This evening, I made a batch of strawberry jam. I always find it difficult to get it to set - will this be OK? 
I listened to night's Prom Beethoven's 5th symphony, while I boiled the jam.