Re: [Elecraft] K2: audio thumps and pops on key closure - is K1 app note relevant?

Thanks Don. This is a relatively new K2/100 # 6998 and the KPA100UPKT mod has been incorporated, as far as I understand. I'll try the resistor cap mod to the drains of the mute FETs on the K2 control board and see what happens. 73, John VK7JB -- View this message in context:

Re: [Elecraft] K2: audio thumps and pops on key closure - is K1 app note relevant?

John, A long time ago, there were pops and thumps with keying in a few K2s having the KDSP2 and KPA100 options. It was coming from the KPA100 T/R switch, and several changed capacitor values in the KPA100 to combat it. Check your KPA100 - if it has red toroid cores at L15 and L16, then

[Elecraft] K2: audio thumps and pops on key closure - is K1 app note relevant?

Hello Group, I've been using my K2/100 on CW a bit lately and have noticed that there are low frequency thumps/pops on the receive audio at the rx to tx transition - ie onset of keying (key closure). They are most noticable if the noise floor is high or if there are other signals in the receiver