Back in the United States there is a law governing low power RF devices. As a general rule, you are able to build a transmitter that can broadcast in the AM or FM band that has a power less than 100mw, an attenna of no longer than ??? feet, to transmit no fathrer than (?)500 feet.
I’m a little rusty on the rules but Radio Shack inludes it in their electronic projects.
Now if it’s an off the shelf device… it would have an FCC sticker, like a cordless phone. The rules say that you may not created and must accept interference from the primary services on the band.
Too make a long story short. If you bought it off the shelf here… what is it licensed for?
And you’d want to check to see if the 100mw rule (FCC Part 97, I think) applies here in Taiwan. Good luck. Let us know how it works out.