Lee Felsenstein on voltage dividers

We recently covered voltage dividers in our Ask MAKE column. In the above two videos, done by our pal Jeri Ellsworth, computer industry legend Lee Felsenstein (member of the Home Brew Computer Club and Osborne designer) explains voltage dividers and how to calculate them. Things get pretty thick by part II and I pretty much got lost, but sharper math heads should prevail. These videos are labeled as “Lessons from Industry Legends.” What a cool idea. I hope Fatman and Circuit Girl do more of these in the future.

Fatman and Circuit Girl

2 Responses to Lee Felsenstein on voltage dividers

1. at 3:19 (second part) he says that the ratio R2/R1 cant be bigger than one, but alpha can.
alpha cant be bigger that one, since Alpha=R2/(R1+R2) , so R1 should be negative to make Alpha bigger than one

2. That’s a nice explanation for students BUT once you have your theorical values, you need to go back into your maths with real E48 or E96 values.
So for me it’s not the most effective way to calculate a bridge divider if you work in design.