IR Pass-Tru

I am in the process of setting up the new USB-UIRT that I just received. I have a very basic question that is causing me issues. Does the jack for an additional emmitter pass the received IR signal automagically or must I program every transmit into girder? I honestly assumed, possibly incorrectly, that if I plugger an ir blaster into the external jack, that all signal received by the UIRT would be replicated to the external blaster. Do I need to rethink my setup?
many thanks,
David Nowakowski
many thanks,
David Nowakowski