[PJL]

When the HT was shorted and the fuse failed, it is quite possible that there would have been a large transient from the mains transformer although I am surprised it would have been enough to take out a slow blow fuse. The voltage readings don't make much sense although the ones on the left will be the AC input and will be floating. I would have liked to have seen the 6.3V AC reading.

As Freya has said, don't just buy one fuse! If it has caused faults in the transistor amplifiers the fuse will blow again.

An option to save a fuse is to power the radio through a lamp limiter and clip your meter on the 10A current position as a replacement for the 2A fuse. It must be on a lamp limiter or you might otherwise damage the meter.

If the current is much above 1A switch off quickly as it is likely there is a fault in the transistor amplifier, otherwise, it may work but probably not too well. You can then remove the meter and lamp limiter, insert a new fuse and hopefully it will be working again.

If the current is much above 1A then we will need to fault trace the amplifiers.