Emulating a key being pressed down continuously - DCS-Skunkworks/DCSFlightpanels GitHub Wiki

Following images shows how to do this on the Switch Panel. For Stream Deck the procedure is the same, you just use the "Key press" configuration for a certain button and use the options for "... Button Pressed" and add VK_NULL to "... Button Released".

VK_NULL, means [Virtual Key NULL] where null means "having no value". A VK_NULL doesn't produce a key press but it used to cancel other key presses being active.