|R-390A - still glowing
Dallas also helped make a complete inventory of valves, lamps and other parts that could come in handy during the next 50 years or so.
This R-390A is a relatively new one, manufactured in 1967. Its pre-Mjelde history is rather obscure, but there is reason to believe that it was one of the workhorses at a Norwegian Army Sigint facility. They were supposed to be demolished after completing service, but story has it that some operators who were also radio amateurs managed to save some of them. I bought it from a radio amateur in 2004.
The R-390A hasn't been among my most important DX receivers, however in many ways it's still a reference receiver for todays' SDRs. Although it can't compete with the versatility of SDRs, on single frequency monitoring it is still number one.