Hi Does anyone have the measure (in mm) for the round septum (OM6AA) described in latest (1/2007) DUBUS? Can I use the same the 4-step septum from OK1DFC? Why are 5 steps better than 4 steps? I will use the measure only to fabricate one psc just helping a friend to be 1296-EME-QRV. 73 Super tnx de Sven SM5LE