GPI and Tally Interface connects to an ATEM switcher and provides 8 contact closure Tally outputs.
Tallies will be displayed when connected to an ATEM switcher to indicate their "on-air" status and you can even connect multiple interfaces together to increase the number of tally outputs.
Professional VTR Solid State Recorder - Version 2
Optic fibre camera controller with tally and intercom
Talkback and tally 4 x optical fiber converters
HD Character Generator
Control Panel for Blackmagic Design Atem 1 Switcher
1 M/E production switcher with 8 inputs, DVE, 9 layers for Mac and PC.