I'm back from another hiring venture for engineering technicians. The field is called multi-craft maintenance. Another name is "mechatronics". It seems that finding people with the right broad skill sets is very hard. A lot of the promising candidates haven't refreshed their basics for many years. I mentioned to a few candidates some resources which they might want to have to brush up on their basic skills.
So, If you stumbled across this looking for hints, here are a few key trade resources: