I saw this beautiful old machine on eBay, and couldn't resist it. Comes in a brass case with carry handle, and is encased in walnut-effect Bakelite. The screws and terminals are solid brass, and it actually smells of pipe tobacco. I have tested it, and wonder if anyone can verify it really is working correctly: Open circuit voltage, crank speed 120 rpm: 400-420V. However, if I do 1ns peak detect, the voltage max is 561.5V. Needle reads very close to, but not quite, infinity. Short circuit current: 6 mA DC. Needle reads dead-on 0 ohms. Attaching resistors across output from 10K to 10M results in a reliably accurate reading. Scope shot: 2ms/div. 20V/div x10. DC coupled. Sorry for the wobbly shot - it's hard to capture while cranking! Do you think it's 'calibrated' and working OK? I'd rather not open it, as the original lead metal plugs are still present, with a maker's stamp, suggested it's not been opened since manufacture, approx 1940. If there is a fault then I'll open it for service. Serial number is 282427. Oh, for the days when one could chuff away on a pipe, cranking a Megger and testing installations.