JB wrote:

There are RF tubes that can do up to 10 meters with plenty of gain and
much better overload capabilities than what's out there now. It might
cost a fortune to use that quality of filtering in a general coverage
receiver, but you COULD build a really first class hybrid that blows away
what's out there.

I did, and it didn't "cost a fortune". I got the crystal filters at a
Rally, I had many of the other components in the junk boxes, and I just had
to buy a few valves and some coil formers. I built the cases myself, and
the internal module boxes are just soldered up PCB material. I found the
reduction drive in a junked HRO, and bought the tuning capacitors very
cheaply. Frequency indication and relative signal strength are shown on an
LCD display.

Bob