Update. 14 out of 47 didn't hatch. On examination 12 must have been unfertalized, and 2 only developed about 50%, not sure why, but now at least I know the incubator is working good. 42 of the eggs were for a friend who just lost 15 hens to a stray dog. She only has one rooster for about 20 hens, so that is probably the main problem with most of the eggs that failed.
So now I know the incubator can be trusted so I am ready to get some dark eggs to hatch, maybe BC Marans, Welsumers, or if I can find them, Penedesenco.
What a wonder, put eggs in a warm box, and in 21 days you got little chicks, amaizing.
TR in AR