Do you have any learned signals for the same device?

That 73H is only part of the information you need to construct the Pronto Hex. It is probably all of the information that is different between functions of the same device but none of the information that is the same across all functions of the same device.

You can use DecodeIR with either DecodeCCF or IrTool to decode learned signals to find the infomation that is common across all functions of that device. Then you can use MakeHex to construct new signals from which you can select function 73H.

[Link: hifi-remote.com]
[Link: hifi-remote.com]
[Link: remotecentral.com]
[Link: hifi-remote.com]