Bruce, there's two or three things I would do as soon as possible:

1st:  replace any wiring where the insulation is brittle and flakes come
off.

2nd: protect yourself and others by using an electrical outlet with an
GFI (ground fault interrupter).

In a nutshell a GFI "compares" the current flowing in the hot leg with
that flowing in the return or neutral; if they differ by more than a few
mA (a mA is 0.001 Amperes) due to some leakage or fault (e.g. a person
about to get a shock), the GFI will trip and cannot be reset until the
leakage/fault is removed.

By the way, prior to GFI, equipment that was transformer-isolated was
considered more safe.  However, a transformer today now isolates the GFI
and defeats its intended operation.

You can buy either a GFI circuit breaker which is installed in your main
electrical box, or a GFI receptacle which replaces a conventional outlet
at most hardware stores.

3rd: protect the equipment by installing a fuse of the proper rating.
While the GFI will take care of leakage and faults, it will not protect
the equipment if some malfunction (e.g. stalled motor) causes more
current than normal to flow.  If you don't want to install a fuse holder,
you can use a plug with an integral fuse (these type of plugs tend to be
a little bulky).

Vince Negro

 [ I believe that all new homes in the US have GFI devices to protect
 [ the electrical outlets in the kitchen and bathrooms.  If a fuse or
 [ circuit breaker is installed in the piano to protect the motor (a good
 [ idea), it must be rated for motor-protection service.  Ask at a store
 [ which sells to the trade electricians and heavy appliance repair
 [ shops.  -- Robbie