The RF Amplifier
As the signal is still so weak, it makes sense to try to amplify it as soon as possible.
and, now that the vast melee of frequencies has been reduced to a manageable
rabble, this seems as good a time as any.
Amplifiers designed to cover a very wide range of frequencies are both difficult to design and expensive to manufacture but, thanks to the now-reduced range, a good design with plenty of amplification becomes simpler. And, as a bonus, it's quite easy to design an amplifier which also includes some more filtration.
Take a look at the picture of a typical radio frequency amplifier stage in an inexpensive radio - alongside the transistors, other components you've come to expect by now: capacitors and coils.
Our wanted signal is getting stronger and nearer our grasp all the time!