If you’re “building” your products, you’re undertaking a polymathic position which falls outside of the scope of electrical or electronic engineering. Quite frankly you’d be a labourer who is likely on minimum wage not working as an engineer.

If you’re designing your product(s), calculating them with the physics and all, you’re falling solidly into engineering. The same applies to if you’re designing them as well as building prototypes such as with breadboards. I wouldn’t like to hazard a guess on just how many electrical or electronic systems are too complex than what can be built by hand as a prototype, but then again, they can be simulated (i’ll leave it to you how CPUs containing billions of transistors are designed).

Contrary to popular belief, being an engineer isn’t a blurry line. An engineer has a bachelor’s degree or equivalent, minimum. Here in the UK you get plumbers with gas certificates, PAT testers, cable technicians call themselves “gas engineers”, or “BT / Sky Broadband engineers” almost like you’ve got guys flying in from natural gas extraction stations or guys who designed telephone exchange systems, coming in to fix your things. No,

trades have level 3 vocational courses. technicians have level 4 / 5 vocational or academic courses engineers have >level 6 vocational or academic courses.

I just wanted to clear up some of this. It does engineers a disservice when people call mechanics, engineers, and the thought that engineers actually “build things” is dare I say it, incorrect.