In IrScrutinizer: for the "Protocol", select "RC5" from the pull-down menu. In IrScrutinizer, that protocol has two parameters: D (device), and F (function). From the context, we conclude that
Address: 13h (group 19: Pre-Amp2)
means that D=19 (or 13 in hexadecimal). It is the parameter that is constant for all commands. You can enter either form; using the prefix "0x" to indicate hecadecimal (as in the sceendump).
In the same way, the command number is the "F", enter as decimal or hexadecimal as you like. After entering protocol and parameter values, just press "Render". (Earlier versons said "Generate" instead of "Render".)
(Strictly speaking, there is a toggle parameter ("T") too, but for most purposes, you can just ignore it.)
The full manual is available here: [Link: harctoolbox.org]