I always wanted cadence display for my bike, to improve my training, but...
All the usual "bike computers" are too small, difficult to see, have problems when used on recumbents (wires too short if wired versions, out of reach of signal if wireless) and all this kind of nonsense...

I want simple, large and easily visible display with easy sensor wiring.
You can get things like that on ebay for very little money:


but... they tend to be 8-24V, 5-9999rpm which is not exactly what I want either (I'd prefer 5V and 0-100 rpm).

So, the question to all the electronic whizz kids out there - what's the best solution???
I have googled and so far haven't found anything