[DonRotolo]

I think you're saying that you want to use this system to send data that isn't the temperature information it was designed for. Is that correct?

If so, then you can decide to just use the Radio parts, or the whole system, to send data. If you use the radio parts only, then it is up to you to decide how you want to modulate that data. Look up "AX.25 Packet" for one example I'm familiar with. If you want to use the whole system, then you need to figure out what modulation/encoding scheme the manufacturer has used. It could be something standard, or something they developed themselves.

The best way to find out is to ask the folks who designed it. Identify the manufacturer from either the packaging or the FCC ID Number (all transmitters must have one, and you can link that back to the manufacturer via online search).

Next is to do what eagle suggests: have it send some known data and decode the bits manually using a storage oscilloscope or data analyzer.

The audio doesn't help much. I can tell that it's sending some bits, likely without protocol since there doesn't seem to be a preamble. ("Protocol" means some method of encoding the data do it doesn't get lost easily. Preamble is a brief burst of non-data bits to fill the time until the transmitter gets up to power and stabilizes)

Just a word of caution here: Just because you have something that sends data from here to there doesn't mean you can use it to send some other data. If you give us more information on what it is exactly you want to do, and what you think this device will do for you, along with the timeframe for getting it done, we can get much deeper into this.