[Elecraft] [KX3] Digital modes: proper ALC for full output power?

[Julia Tuttle]

Ah, okay, the manual didn't tell the whole story. I assumed if I got 0-1
bars, I was loud enough to hit full output power. I tried aiming for 4-5
bars and I'm getting full output power. Thanks to the folks who suggested
that!

So while I'm here, is it okay to run 15 W out for 15 seconds straight at a
50% duty cycle? The manual recommends 5 W, but FT8's duty cycle seems to
keep my PA temperature under 45 C. Are there other issues besides
temperature I need to worry about?

On Thu, Mar 4, 2021 at 9:36 PM Bill Frantz <frantz at pwpconsult.com> wrote:

> Hi Julia -
>
> Running the Transmit Gain procedure (page 33 in my manual) is
> the usual first thing to do when the power output seems "wanky".
>
> The general recommendation for drive level from the computer is
> 4 bars with the 5th flashing. If the drive level is too low, the
> output power will start off low and then build to the power
> output setting on the radio. If the drive level is 4 bars with
> the 5th flashing, the radio will start close to the power output setting.
>
> If the drive level is too high, you will drive the radio into
> using automatic level control which will produce a distorted
> signal on the air.
>
> If the output power is stablising at levels lower than the
> setting, try the Transmit Gain calibration procedure.
>
> 73 Bill AE6JV
>
> On 3/4/21 at 2:35 PM, julia at juliatuttle.net (Julia Tuttle) wrote:
>
> >I'm trying to get my KX3 set up for FT8 and JS8call and all those fun
> >modes, and I'm running into a bit of trouble with setting the audio
> >interface volume and mic gain.
> >
> >The KX3 manual suggests aiming for no more than 3-4 bars of ALC indication
> >to prevent distortion, but if I do this, I don't always get full output
> >power.
> >
> >Initially I chalked this up to the firmware reducing output power from
> >heat, but it's proportional: if I ask for 10 W, I get 7; if I ask for 5, I
> >get 3, and so on.
> >
> >It also doesn't always happen!
> >
> >Any ideas?
> >
> >73s,
> >
> >Julie
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