I thought I would pass this along, for whatever it is worth.? I have two Ver 3 and one Ver 4 uBiTX rigs.? I have replaced K3, KT1, KT2, and KT3 relays with Axicom relays which has knocked down the 3rd, 5th, and 7th harmonic levels from -35dB to below -50dB on all 3 rigs without any board modifications to the LPF circuits.? This may be anecdotal but with 3 rigs showing the same results it may be something to consider.? I purchased the relays from Mouser - part # 655-V23105A5403A201.? Cost was $2.89 per relay plus shipping.? I've attached photos (sorry for the blurriness) showing the before and after results on my Ver 4 rig.
--73--? Mike? --? W0MNE

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