Problem: The NCAC signal at NeoSat satellite receiver was not available.
Diagnostic : As this sources is used as standby input source so we normally checks all take over the charge of duty. It was detected that all other channels were ok but only NCAC channel was disturbed. we checked the MCR at HQs NBH they replied OK report on down link.
Rectification: The input sources of receivers swapped and problem vanished because during last activity of maintenance on satellite receivers these cables were swapped by mistake.
Root Cause: The root cause was declared as that the LNB to Receiver matching(re-tuning) was not done during re-connection of feed cables with receivers.