Here is a nice looking regulated power supply to power your farm tube radio.  This unit has a regulated 2 volt output and a regulated 90 volt output.  This powers supply will power up your old 1940s battery operated farm radio.   I have sold several of these beauties and everyone has been very satisfied.  They have an on/off switch in the cord and there is an LED that lights when the power is on.  It will fit in the back of the cabinet just like a battery.  Give it a good home.  It measures about 7" X 2 1/2" X 3".