You can create a table inside your customised object(say MyObject) and the column type match your properties, ie,he first of type datetime and the second of type real. and then convert it to a repeatgroup ,for example its name : tableA
and on parent model you can instantiate your object and on the property panel, you will see the repeatgroup to assign. you can create a table directly via the schema dropdown list with the name MyObject, select MyObject.tableA and the table will be automatically created. the next step is refer to this table on the properties panel.