[Elecraft] K3 TX Power

[iain macdonnell - N6ML]

A couple of basic things...

1) Perform the TX gain calibration (see the Owner's manual)

2) Adjust the audio level from the sound card (if applicable) and the
line-in level on the K3 until you see 5 bars on the ALC meter when
transmitting JT65.

73,

    ~iain / N6ML


On Fri, Aug 16, 2013 at 9:33 AM, Ray Coles <raycoles96 at gmail.com> wrote:
> For the last few months I have been focussing on datamode operation, and
> putting a lot of hitherto unobtainable DX in the log as a result.
>
> I have noticed a problem with my K3 on all bands related to TX power. My rig
> is a K3/100 plus a KPA500/KAT500 combo which remain on STBY for digital
> modes of course.
>
> My problem is: I dial in a power-setting on the K3 and for the first (let's
> say JT65) transmission the actual transmitted power as measured by: the K3
> itself, the KPA500 and my inline MFJ duelling banjo wattmeter is always much
> less. If I dial in 100W I would get 20-30W during my first transmission,
> 30-50W on the second, and 75-80W on the third. On the 4th or 5th minute of
> transmission it will reach the dialled in power setting. The SWRs are all in
> the 1 to 1.5 range and I can see no external problems.
>
> This is not good because I would really prefer it the other way around, once
> someone has responded they will stick with you, but if they don't hear you
> on the first call, you're toast.
>
> To offset the problem I turn the power up to 100W and cross my fingers that
> they will hear my first (weak) transmission. Unfortunately by the time I am
> done, I am putting out more power than is healthy for other users who may
> find that the weak signal they are working is pushed down by their AGC due
> to my strong signal in the same window.
>
> Attempts to adjust the power during a QSO fail, with a minor downward
> adjustment (say from 100 to 80W) resulting in the true output power
> plummeting to 20W and the cycle starting over.
>
> This doesn't seem to be any kind of "warm-up" issue (my first suspicion) but
> maybe some kind of logic or control feedback issue.
>
> Has anybody else experienced this? Is it me?
>
>
>
> Ray Coles, C.Eng. M0XDL
>
> 10 Littlemoor Road,
>
> Weymouth DT3 6AA
>
> Tel: +44 (0) 1305 833699
>
> Mob: 07831 516517
>
>
>
>
>
>
>
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