Making Satsuma Marmalade

We've two satsuma trees here on the place - both loaded with fruit.  Until I encountered these trees some years ago while visiting Cairo with Joe, I had no idea that citrus trees ripen in the winter.  For that matter I'd never even heard of a satsuma = a tangerine of a hardy loose-skinned variety, originally grown in Japan. 

We are feasting on them daily - especially Levi, who frequents the 'sweeter' tree.  I'm making my first batches of marmalade - basically jelly made with citrus juice.  I'm trying a method that does not involve the use of SureJell (powdered pectin).  This 'old-fashion' method relies on concentrating the naturally occurring pectin content of the fruit, and testing for a 'set' as you cook the jam/jelly.     

I now understand the widespread use of powdered pectin.  My first batch set a little hard and the second batch too soft.  My crew isn't particular about such nuances - they'll take their marmalade anyway it comes.