Analog tach replacement

Bob Noel writes:

I highly recommend having this feature and its relative, "mag drop".
It would be a shame to switch to an electronic tach without getting
such basic features as a result.

In fairness to the R-1, it does have the "mag drop" feature.

O.k., I'm stumped. How can it tell you that it's measuring mag drop
without telling you that one of the mags isn't firing?

ah - I think I may have been confused and thus confused others. I read
"mag drop" and assumed you meant "RPM drop" when checking mags during
a run-up.

I was using the same definition. I'm trying to figure out how the R-1
can say "here's the drop in RPM due to one mag not firing" without
the operator figuring out that one mag isn't firing.

--kyler