Re: [Elecraft] K3 TX spurs?

There was a serious spur problem with K3's that have C3 installed. Read about it at: http://elecraft.365791.n2.nabble.com/Unstable-KPA3-100W-td5742537.html#a5742613 73, Joe W8JH K3 1713 -- View this message in context: http://elecraft.365791.n2.nabble.com/K3-TX-spurs-tp5936691p5943712.html

[Elecraft] K3 TX spurs?

I think I recall a thread about spurs being produced by a K3's TX, but didn't pay enough attention at the time. I've since become aware of a K3 that appeared to have two spurs showing up on my P3. They were about 30db down from his very strong carrier on 7031 KHZ, and equally spaced about 1

Re: [Elecraft] K3 TX spurs?

During the recent NAQP, I heard these 1 kHz sidebands on a nearby station's signal on 160. (Perhaps the same station Ken heard?) It turns out, his K3 was overloading his wimpy power supply, and making it go into current limit. There was no sign of the spurs at slightly lower power. He could

Re: [Elecraft] K3 TX spurs?

One possibility: “microphonics” modulating the synthesizer. The source is typically the sidetone being played through the internal speaker. A quick fix is to not use the internal speaker. The solid fix is the Elecraft synthesizer stiffener mod kit. Easy to determine if this is the problem: