N Cook wrote:

Just repaired a Carlsbro Hornet Combo , made in UK, 1984.
Seems as original inside otherwise.
Unusually the amp separates into 2 sections separately connected to the
wooden casing and so electrically isolated as far as any earthing.
The mains transformer is on the rear panel which has a proper earthing point
from the IEC mains inlet.
Power supply is plus and minus rails but the common is not connected to
ground at all. The power and signal lead to/from the pre-amp / reverb is 4
lines : plus , minus , common , line level signal with no earth connection.
The front panel is connected to the common , not to earth anywhere.

There is much more noise immunity from general stray pick-up if I run a wire
from the earthed back plate to the front so bridging common and ground.
If made permannent,internally, would there be a safety issue,

no

or in fact,
leaving as is , is that safe ?

if its double inuslated, yes, if is single insulated, not entirely.

It might be floating in an attempt to avoid earth loops.


NT