Quoted from Quench:Again a smoking transformer is indicative of a short circuit downstream in the game - most likely lamp based due to high currents and it was fused with a nail..
It is also pretty easy to burn up the high voltage winding (display voltage) in a transformer due to over fusing…..when for example a rectifier diode shorts in the high voltage section, this thin wire winding will not survive if there is a 10A fuse in place in stead of a 0.25A...…. I've seen this more than once unfortunately.