yes, that was me. No splitter - realized only a few moments into trying that scenario that it negatively impacted my signal.
Thanks to your suggestions, and lots of reading past few days, I've now consolidated the two RPis down to one and have all three services (FA, RB, FR24) running and feeding successfully.
I've also tried the gain setting - no improvement, receiving the best I can from within the attic. I reside in a very tree'd neighborhood so I'm assuming that is impacting my distance.