RFID Toys

Could be RFID, but I could think of other techniques.

I assume it was contactless. A simple relaxation oscillator can produce a wide range of frequencies easily detected by a uC using just a capacitor. The advantage of this technique is that the "contacts" need not be good, and may not even be exposed. Imagine an SMD capacitor placed over a square with plates that correpond to the solder pads at the end. Even if the contact area where covered by a thin film it would be possible to get a variable frequency.

In the case of RFID, it could just be the simplest possible case, that is a resonant circuit where you simply measure the frequency at which the "arial" is most loaded, without actually modulating the carrier.

Al wrote:

From the page below (damned top poster):

"Using the newest technology (Radio Frequency Identification), Maestro Mouse can play 24 favorite Holiday tunes on his baby grand piano."

On a sunny day (Sun, 31 Dec 2006 12:03:18 -0500) it happened krw wrote in : "Using the newest technology (Radio Frequency Identification),

Not cheap, 55$.

The other day, a friend came over for lunch and brought a gift she had received. It was a baby grand piano, about 1 foot long, that had a mouse dressed in holiday clothes playing it.

OK, here's the good part. The tune it would play would be selected by a

When you placed the block on the music stand, the mouse would play the piano with that music. At the beginning and at the end, the mouse would make comments.

It seems to me that the piano is activated by an RFID tag in the music sheet block. It was very amusing to watch and play with.

Has anyone had any experience with these and knows how they work for certain?

If you want to look it up, go here:

No, I am not afflicated with the product.

Al

PS: Oh, and why didn't I thing of that? .

------------ "Imagination is better than knowledge." (Einstein)

Maybe you need more knowledge on imagination :)

No contacts that I could see.

Al

Aside from security tags, this is the first instance I had knowingly come across an interesting application of RFID technology.

The "sheet music" has to be almost touching the holder for the gadget to start working.

I no longer have access to radiography or else I would have taken one of the "music sheets" and X-rayed it to see how it was configured. Anybody actually taken one apart? Since it isn't mine, I won't do it.

Al

Anyone got a spectrum analyzer/antennas?

On a sunny day (Mon, 1 Jan 2007 12:28:32 -0500) it happened krw wrote in :

Is it not 13.56 MHz? Short wave radio should do? (There are also 2.45GHz tags, works up to 7 meters, but I think not these).

Just looked it up, it is 13.56 MHz with +-423kHz sidebands. A lot of bandwidth! So you should get a carrier at 13.137 and 13.983 MHz on the shortwave radio too :-)

My estimate is that all that is in the tag is a song ID. All the rest is in the capacious and complex piano part.

probably, but there's room in a 64K mifare tag for a whole song... and probabnly enough room in a 4K tag.

Bye. Jasen

There were children's 'CD' players which had plastic 'CDs'. Clearly the disk merely coded the internal player and had no music.

After the first "music sheet" is left in place and the music has completed, the toy will then play the others in random order. So the tag must only have an ID in it for that particular song.

This has been a nice discussions. Thanks for all your inputs.

Al