I've just got a new Theremin as a gift - help!!

First let me make it plain that I am and always have been a fan of the theremin since hearing them in the sci-fi movies of the 50's and onwards (I'm 56 myself). Anyway, knowing this my son has just bought me a theremin - or at least I think it is - on ebay. It's came all the way from Japan and the instruction booklet with it is all in Japenese, so apart from a few visual pix, I'm pretty much stuck as to knowing if there is anything in particular in there that I should know about it sepcifically. It is a 'Premium' and comes from Gakken.co.
Can any of you out there tell me anything about it...including is it a good one, very good one or other?! All tips would be most appreciated and welcome!
Best wishes from me here in Lincoln, England.

A very good present indeed!

Have a look here:
http://www.youtube.com/watch?v=bJdQJpne1g8

I guess it will help a bit.

Actually, this Youtube clip does the trick! Thanks!
Anything else anyone else might like to add, still welcome!!

There's another one:

http://homepage2.nifty.com/yamamoto_jun/e/tuning.htm

..since you've pointed it out, I see there's quite a few YouTube clips using this model!