Recently purchased an Omni D-C series. It does not have the optional filters: TT #217--500hz for CW, TT #218--1.8Khz for SSB. Any benefits to the Inrad filters over the TT? #759--400hz-CW #761--1.8Khz-SSB What is an average price used for the above filters? Thanks, Jamie NE4TT --- [Pre-scanned for viruses by Internet America.]