I'm about 20 hours into my PPL, so maybe I just haven't gotten to this part yet.
Suppose I'm flying KFCM to KRNH and I want to request clearance across the bravo. How do I figure out which approach frequency to contact KMSP on?
From liveatc.net, it looks like approach is 121.2 or 126.5 (for low altitude). At skyvector, 121.2 and 126.5 are listed under Class B. From the Chart Supplements - neither of those frequencies appear. Am I just looking at the wrong information?
I found a similar case for KPBI where the approach frequency (124.6) doesn't show up on the chart supplemental.


Technically, I could avoid the entire Bravo space, but if I wanted to request a transition through the Bravo and over the airport would I put that request into FSS or after contacting approach?
– Shuo Mar 29 '21 at 20:52