The 120V version of the 730 has a primary power switch on the back, but the 120/240V version
does not. Not sure about the 220V version. The main power switch is the touch-sensor button
on the front, which is powered by a small transformer/supply that's always on(unless the rear
switch is off, on the 120v version at least). For this reason, it is not possible to bring it
up on a variac, but I would not even consider that necessary. Other than occassional minor
issues with the low voltage power supply(+/-15V for preamp & tuner), their pretty damned
reliable. Just be prepared to replaced dozens of tiny lamps(14v/40mA) in the front panel,
which are a bit challenging to get to.
The 730 is one of my favorite receivers in the world.

--
Stephen Sank, Owner & Ribbon Mic Restorer
Talking Dog Transducer Company
http://stephensank.com
5517 Carmelita Drive N.E.
Albuquerque, New Mexico [87111]
505-332-0336
Auth. Nakamichi & McIntosh servicer
Payments preferred through Paypal.com
"N Cook" wrote in message
...
Incredably neavy lump. Unused for years and unknown history and mains lead
is mildewed so
I wanted to insppect innards first and then power up on a variac.
Eventually twigged how to remove the top cover. Innards perfectly clean and
healthy looking.
But now stumped - where on earth is the on/off switch ?

electronic hints and repair briefs , schematics/manuals list on
http://homepages.tcp.co.uk/~diverse