[K3] [Elecraft] K3: 1. Loud audio blast on power up 2. Main/SUB balance

[Ed K1EP]

At 12/10/2008 03:03 PM, Enno, PF5X wrote:

>Hi,
>
>Just loaded F/W 2.72/1.98 with the "Send all firmware" option (so including
>data tables). The short audio blast is still there if you are tuned to a
>signal when switching on the K3. It really hurts your ears as it seems that
>for this short period the AGC is not yet ON.

I recorded the 160M CW contest this weekend using the LINE OUT=phone 
or speaker option.  I also noticed the short burst when the radio was 
turned on.

>Any fixes planned for this (change boot order in DSP such that AGC assumes a
>signal being present until the RX really starts to receive) ??
>
>BTW. The updated action of LINE OUT=NOR now with outputting monitor audio
>during TX is great.

Yes, this should make recording a lot easier, thanks!

>I have the set the CONFIG:SUB AF to BALANCE. When looking to the monitor VU
>meters on the microKEYER router software it appears that the SUB output is
>lower than the MAIN output with the balance knob in the 12 o'clock position
>(after equalizing both main and sub with double tapping A>B). This is effect
>is also audible (~6dB difference).

What I noticed, but didn't investigate, was that there was a DC 
offset in the SUB audio output.  I was using Audacity to record the 
audio.  Using the LINE OUT to a line in on my computer.  I noticed 
that monitoring the sidetone showed close to a zero (if not zero) DC 
offset for the left channel or the MAIN Rx.  The right channel 
however showed a substantial DC offset.  I haven't played with the 
new Beta yet, nor have I looked closely at the recording.