Just picked up a 1930s Battery operated Coronado

[Electronic M]

I used to have one. It wasn't a stellar performer and the cabinet was beat up so I got rid of it. I think it took 90V for the B+ supply and 1.5V for the A supply...the A supply voltage is easy to confirm by googling for the data sheet for 2-3 of the tubes and using the lowest filament voltage. (The audio outputs of battery radios often used a tube of double the A battery voltage with a center tap...the ends of the center taped filament would be jumppered together to halve the opperating voltage and double the current)