Applying a satin finish over gloss

Yes. You can do a Satin finish, however, I would recommend that you do a fresh coat of gloss before attempting a coat of Satin.

Here's why. Seeing as you applied the last coat way back in '94 I'm guessing that a lot of 'stuff' has landed on the floors surface in that time. Some of that 'stuff' like, fly spray, furniture polish, laundry spray, things of that nature will of left a residue on the floor.
The Satin coating most probably won't adhere very well to your existing finish, particularly if there are contaminates as I've described. For that reason I highly recommend that the floor gets a fresh coat of gloss first, which is much easier to apply and has great adhesion properties and will hide just about anything that the floor has copped over the years. This new coat of gloss creates an excellent base for you to have a trouble free coat of Satin as your final finish.

If, on the other hand, you just try and apply a coat of Satin over what you have there now there is evey chance of you having a host of problems with delamination, spots, bits where it won't take properly, rough patches that sort of thing.

First up, you will need to cut back the floor pretty severly, which is a light sand that completly scratches up the entire surface of the floor leaving the whole thing uniformly dull. I've added a couple of photo's down the bottom to visually show just what a decent cut back looks like. The second photo shows how dull it should look.

So, cut it back, vaccum and then apply a coat of Wattyl 7008 2 pac. Then cut it back again, vaccum and then apply your Satin coat. I recommend Polycure Super Satin, which will have to be purchased either off a local floor sander or floor sanding supply company.

Good luck.