Not to tell you this is exactly off the shelf but a Rasberry Pi can do this with some work.
https://www.raspberrypi.org/forums/viewtopic.php?f=41&t=83861 as example.
If you don't do this yourself, a programmer can make this happen for much less than a digital signage company.
I run tennis tournaments. I have tournament software built in excel on multiple sheets. I need to be able to display different worksheets on different screens from the same laptop and they all need to be displayed wireless. For example I need the upcoming matches sheet to be constantly displayed on one tv, while another tv is constantly displaying a players check in worksheet. Thanks for any help you can give on the best options for setting this up!

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