I don’t know, but those amps were the **** back in the day! Lead guitarist in my highschool band played one, then added the matching 112 cab under it, and dango, big beautiful noise.
The easiest and cheapest way would be to get an external transformer. You'd have to examine your particular amp to see if it already has a transformer that supports both voltages, but most likely do not.
A conversion transformer probably easiest. But, someone should investigate, it's possible your power tranny is 120V also, maybe not wired to it, ot a changeover inside. Not sure.
A few years back I bought a Fulltone Tube Tape Echo from Finland. I wanted it because the chassis was beautiful polished chrome with a lid unlike the earlier models. It also had 220V. I took it to a veteran friend of mine who was a electronics tech. He just rewired the transformer and maybe added a new plug cord! That was it! I am hoping it can be done with the amp as well, but I don't know. I may have to buy a new Mercury transformer. Thankyou all, Albert
You will need to change the power transformer. The RD50 models use one transformer for the 220V and 250V regions and a different transformer for the 100V and 125 V regions.
It might be easier to utilize a 1:2 step-up autoformer, depending on the specific voltages of your power grid and the requirements of the amp.