Hallo, has anyone done any IMD measurements at 10kHz or less with the 2.1kHz and/or 1.8kHz filters? If so, please contact me directly. Thank you es vy 73 de toby -- DD5FZ (ex 4n6fz, dj7mgq, dg5mgq, dd5fz) K2/10 #885 K2/100 #3248 K3/100 #67 DOK C12, BCC, DL-QRP-AG, JN58td