I don't recall the national 300, but had an ncx-300, my first radio. I
wish I'd kept it. all tubes except the vfo, but I digress, that was a
transceiver. I do have a kenwood R-300, all solid state and out in late
seventies as I recall. I finally found on on e-bay as I had sold mine
years ago. Very rare, but a neat receiver.
73s
Butch Bussen
wa0vjr