add skeleton for negative signal sch-sch
add skeleton for negative signal sch-sch

mitdbg/aurum-datadiscovery,mitdbg/aurum-datadiscovery,mitdbg/aurum-datadiscovery,mitdbg/aurum-datadiscovery,mitdbg/aurum-datadiscovery,mitdbg/aurum-datadiscovery