For Sale: Elecraft AF1 Active Audio Filter. Built nicely and working fine. Specs are at www.elecraft.com under Mini Modules. $48.00 plus $8.00 shipping Sell only to the lower 48 states. Paypal. I have two of them. --Bob W1XT K2 #1434, K2-100 #5812, KX1, + + Surprise, Arizona w1xt at rmcgraphics.com