Sounds like RF leakage between the Rad Alt Antennae causing spurious ramping. The rad alt's only track down so if a spurious signal(leakage) is recieved (100 call @ 2500')the rad alt will then try to resynch on the actual ground return signal.
I seriously doubt the problem to be related to the FWC this will only process the audio call outs from signals received from the RAD ALT (In This Case)
Hope this helps Conehead.
[ 13 January 2002: Message edited by: IMA Conehead ]</p>