Time only selection field

Hi,

I have a scenario to create a time only field - for example :
MondayStartTime : [10:23] - MondayEndTime : [15:10]
Etc until Friday

I found this article https://www.linkedin.com/pulse/separate-time-from-date-field-customization-only-microsoft-fuks which seemed great but Calculated fields only reflect what the user sees on the screen and cannot be stored in the database.

So would it be ideal to create a secondary field updated by Java Script when the calculation is triggered ?

I don't want to use a single line text field but if there is no solution would have to go with that.

Thanks,