My first "boat anchor" (not really). It's a university lab isolation transformer. Got it from a flea market. There is no signs of model indication or anything. There's only an inventory sticker on the back saying it's from University of Twente.
I long wanted an isolation transformer. Could have made one myself, but I spared the effort. Didn't really want to buy it. I just talked with the seller, hoping he would put an unreasonable price tag (Dutch people like this :'( ), but he said I could have it for 10 euros. Couldn't resist that.
The unit is well built and preserved. The only thing I don't understand is the purpose of the diode. I opened the enclosure, everything looks nice and tidy except one screw connecting the indicator lamp on front panel. It was loose, that might explain why the first time I powered it it didn't lit up. The tranny seems to be 48VA, made by AMROH (Holland), part number 36.251 . There are additional taps of 2V and 4V which are not connected to the front panel. The box could've made smaller. But, I guess, bench space was no problem "back then". Though I don't really know how old the device is, can't see any date codes.