How can I put my XBee 3 802.15.4 into continuous transmission for RF observation?

I assume there are AT instructions to configure the radio for FCC testing, etc. But I didn’t notice any in the datasheet I found. Are these commands available?

That is something you need to contact Digi Technical Support to obtain.

There are no AT commands available for FCC or any other govt. approval testing. If you are looking to certify your end product with Digi XBee module inside then get in touch with Digi Tech Support or your point of contact in Digi Sales.