A master log is the daily schedule template: it assigns one format clock to each of the 24 hours in a day. When TuneStacker generates a program log for Tuesday, for example, it opens the Tuesday master log, reads which format clock runs at each hour, and builds the day from those clocks.
Most stations have seven master logs — one per day of the week — though you can have as many as you like. You could have special master logs for holidays, pledge drives, or one-off events.
The MasterBuilder window expands to at least 780 pixels tall when you switch to it, to ensure all 24 hour rows are visible without scrolling.
Click New below the master log list on the left. A new log named "- New Master Log" appears. Click the name field above the hour grid and type a proper name — the day of the week (e.g., Monday) if you're using Auto mode in TuneStacker, or any descriptive name if you'll assign logs manually.
Click Main Format Clock to Use → to set a single format clock across all 24 hours at once. This is the fastest way to start — apply your standard clock to all hours, then override the exceptions (morning show, overnight automation, etc.) one hour at a time.
The 24 hour rows each have a dropdown popup on the right. Each popup lists all available format clocks. Click a popup and choose the clock for that hour. Hours are labeled in plain language: midnight (12 AM), 1 AM, 2 AM… noon (12 PM)… 11 PM. Hover over any popup to see a description in the status bar.
The hour dropdown shows "(none)" for unassigned hours. TuneStacker will generate an empty hour for any unassigned slot — that's fine for hours your station doesn't use, but make sure any hour AutoCast actually plays has a clock assigned.
Select a log and click Clone. A copy appears with the same hour assignments. Rename it for the new day or event.
Click Rename while a log is selected. A text field appears — type the new name and confirm. The file on disk is renamed automatically.
Select a log and click Delete. You'll see a confirmation before the file is removed.
On the right side of the MasterBuilder tab is a validation panel. When you select a master log, ClockWork checks every format clock referenced by that log against your loaded library and lists any issues it finds.
| Issue type | What it means |
|---|---|
| Format clock file not found | A clock name is referenced in the master log, but no file with that name exists in the Format Clocks folder. The clock may have been renamed or deleted. |
| Random/Rotate — 0 library matches | A music-selection event in this clock has filter criteria that match nothing in your current library. |
| Play — file not found | A Play event references a file that doesn't exist at the specified path on this machine. |
Each issue shows the clock name as a clickable link — click it to jump directly to that format clock in the ClockMaker tab so you can fix the problem immediately.
Validation runs automatically when you switch to MasterBuilder, when you select a log, and after you make any changes in ClockMaker. It runs on a background thread so the tab remains responsive while the library scan runs.
A green or red dot next to each master log in the list gives a quick at-a-glance summary: green means no issues, red means at least one issue was found.
Validation checks the currently loaded library. After a library reload (⌘R), the dots update automatically to reflect the new data.
Master logs are plain text files in your station's Logs/Master Logs/ folder. Each file contains the assembled content of all 24 format clocks (one after another, headed by # Hour 0 through # Hour 23), followed by a footer section of metadata lines that record which format clock was assigned to each hour. This footer is what MasterBuilder reads when you open the log — the assembled content is what TuneStacker reads when generating program logs.
Whenever you edit a format clock in ClockMaker, any master log that uses that clock is automatically reassembled on disk. You don't need to do anything manually.