I live in a noisy environment (typical S-7) and have in the past complained about K3 audio. I was never sure what was going on but it just sounded rough and unpleasant. The hardware audio modifications I think helped a little and most certainly cleaned up the line-out IMD.
Mostly I operate CW mode using fast AGC. The narrower the bandwidth the more unpleasant the audio became. I operated mostly above 1 KHz bandwidth just to smooth the sound of background noise as anything narrower was just so tiring. So I volunteered for the AGC hold version of the firmware. I can say that I can improve the audio on my end. I can find a way to operate with the rough audio edge reduced, perhaps by 8-10 dB when I look at spectrum lab headphone audio. I am guessing that with fast AGC and high noise that I was hearing IMD products caused by noise modulating the receiver gain and the effect of gain modulation on the noise [or signal] in the pass band. At S-7 the DSP AGC really has significantly reduced system gain so the gain modulation at fast AGC might be substantial in high background noise areas. I never really tried slow AGC for CW mode prior to this and I was not in the habit of riding the RF gain. Note: If I operate with fast AGC I have to reduce RF gain quite a bit for the audio to lose its edge. Fast AGC just isn't working well in my environment. I hadn't discovered slow AGC or AGC off with reduced RF gain as a way to operate. I am right this moment operating with maximum [1.99 second] AGC hold, I will play with different settings over time. Listening to a weak signal and varying the hold parameter I can hear that things seem to improve a little with the AGC hold greater than 1 second, RF gain at maximum. Larger AGC hold is probably achieving something similar to my riding the RF gain control. As a plus I am getting to use band independent VFOs as that is in the prerelease firmware also. So far it works with no hitches. Mike Scott - AE6WA Tarzana, CA (DM04 / near LA) NAQCC 3535 K3-100 #508 / KX1 #1311 ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
