[Elecraft] K3 FIRMWARE UPDATE: MCU 1.87, DSP 1.69 (Finally!)

[Bob Cunnings]

I have set up for PSK31 operation with the new firmware and am getting
exactly what I expect. I'm using a peak reading external meter and it
agrees with the power commanded and the power indicated on the K3
front panel RF meter. First I adjusted audio drive to get 4 bars on
the ALC meter using a pure tone (Digpan tune mode), and could then
adjust power at will with the power indicated on the external peak
reading meter tracking the power control nicely.

PSK31 "idle" average power is about 50% of the key down (single tone)
power. Using Digipan tune mode I see commanded power equal to
indicated power when the external meter is set to read either peak or
average (of course).  When sending PSK31 idle I must have the meter
set to read peak to get agreement with the front panel RF meter, which
makes sense since the change notes state:

 "The RF power bargraph shows approx. peak power..."

 (in the SSB TX POWER CONTROL section).

Are you adjusting audio drive to get 4 bars of ALC with a pure tone?

Bob NW8L

On Sun, May 4, 2008 at 7:27 AM, G4ILO <julian.g4ilo at gmail.com> wrote:

>  I am observing that it is impossible to get the requested power output in
>  DATA A. If I set the PWR control of the K3/10 to 5W then no amount of audio
>  input will get the external power meter to read 5W output on a pure audio
>  tone. Instead the meter reads about 2.5W at the same LINE IN setting that
>  gave 5W out when the power was increased to max. Slowly increasing the audio
>  drive above this level with the K3 meter showing ALC shows the ALC pulsing
>  about twice a second. The amount of ALC shown during the pulses increases as
>  the drive level increases. The power meter (moving coil, average reading)
>  will only go up to about 3.0W and some slight pulsing of the meter needle is
>  also evident corresponding to the K3 ALC display.
>
>  Sending a PSK idle tone instead of a pure tuning tone the meter shows a
>  level a bit below half the level on the tuning tone, commensurate with the
>  K3 limiting the output to 2.5 or 3W PEP despite 5W being requested. The only
>  way to get a real 5W peak is to set the PWR control to 12W and then regulate
>  the power entirely using the audio drive, which is not a very accurate or
>  foolproof way of doing it.
>
>  In PSK D mode where the audio is generated internally by the K2 the power
>  does seem to be correctly regulated by the power control (the K3 does not
>  generate the short "tail" of pure carrier at the end of the transmission
>  like most sound card programs do.) However something is definitely not right
>  with the power level setting. If I transmit in DATA A, then select PSK D and
>  send something, I only get about 0.2W! I have to change mode to CW and then
>  back to SSB and then the power out in PSK D is correct.
>
>  Unlike someone else who reported low output on SSB my own "aaallo" testing
>  has found nothing amiss in this mode.
>
>
>  -----
>  Julian, G4ILO  K3 s/n: 222 K2 s/n: 392
>  G4ILO's Shack: www.g4ilo.com
>  Zerobeat Ham Forums: www.zerobeat.net/smf
>  --
>  View this message in context: http://www.nabble.com/K3-FIRMWARE-UPDATE%3A---MCU-1.87%2C-DSP-1.69---%28Finally%21%29-tp17041394p17045737.html
>  Sent from the Elecraft mailing list archive at Nabble.com.
>
>
>
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