original I'm using a 400 Hz Inrad filter. A most excellent filter. I've not had any need for anything narrower so far. There is also installed a TenTec 1.8 kHz filter but don't really use it much. Ji
they caps "Member, Ten Tec Worshipers Cult". Love it. I am going to have that message printed on my next batch of QSL cards. 73 & happy TenTec'ing, Jim/W4XL up?