Participant Activity Management - New Participant Entry Page
Please enter one or more Call Signs separated by spaces:
Here you can enter one or more callsigns separated by spaces. The expectation is that they will all be capital letters and only spaces but the system will validate your entry and correct any misplaced commas or extra spaces before it allows you to save. Once you have entered the call signs you want hit 
button. In the next screen you will see how the validation works.
Now you will see the input text box with corrected input and a list of what you've entered. If this does not represent your intentions you can edit the text box as much as you want and re-validate as many times as you need until the list is what you expect.
Once you have validated a second time you will now have the opportunity to save. Be sure the bolded list is what you want to save. Each time you make changes to the text box you must re-validate so you are saving what you expect. If there are call signs that are currently not in the system this save routine will create new Wordpress users with default information. This will need to be updated at a later time in the user profile so they will have a name and identifying information. For now their participation will be noted with an appropriate call sign.
Here you will see the list, again validated, after I removed the missing calls so you can see how a clean list with no missing calls looks.
When you are happy hit "Save New Participants" and they will be added to the list on the Participant Activity Management page.