Hello.
I took an old (Octal tube) 5 tube AC/DC radio apart for repairs and wanted to understand the lack of safety in a hot chassis so I decided to experiment.
The very first thing I did was to isolate the filament string from everything else, in essence just a christmas tree light set, including the indicator lamp.
OK, no connection to chassis so far.
Next I isolated the audio section by way of the transformer and worked my way back.
I isolated every part of that radio to the standards of double insulated elecrical safety.
The loop antenna and speaker are isolated as well as the volume pot and tuning cap, in short, no short. ;)
I have tested the radio with a megger to be sure.
http://www.angelfire.com/electronic/...bes/AA5-1.html
So the question now is this.
Why was this not done back then?
To be sure, the radio in question is now equipped with an IEC power connector and grounded chassis.