Audio Levels for WSJT on K2, etc.?

[Steve Kavanagh]

I'm starting to play a bit with JT65 on HF (using WSJT-X) with my K2 and homebrew interface hardware.  The frequency response of the K2 seems reasonably flat, but occasionally I see power dropouts when the tones change.  This is despite always hitting the requested power at any audio frequency using the "tune" button in WSJT-X. It seems to happen less when I have plenty of audio drive - does it make sense that the K2 power control might get a bit confused by switching transients when there is only just enough audio to get the RF output up to the value set with the power knob? For those who are using WSJT modes on the K2 successfully, what ALC readings do you usually run at ? I'm hoping eventually to get the K2 going with transverters for VHF meteor scatter on FSK441 - is the stock OP1 filter wide/flat enough to work well for this mode?  S/N 4509 is the older of my two K2s. Any other hints for using the K2 on WSJT modes? 73,Steve VE3SMA 
 
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[Don Wilhelm-4]

Steve,

On the K2 with any data mode, run the audio up until you see one ALC
bar, and then back it down until it just barely goes out.
That is the correct audio level - set the power to the level desired and go.

One thing about the K2 power level is that it is reset after a band
change or a power level change.  That is better than creating a power
spike.  It takes a couple of dits in CW or a few syllables in SSB mode.  
Because your data audio stream is not syllabic, it may take a bit longer
for the K2 to adjust to the proper power level. There is no work-around
that I know of other than doing a "throwaway" transmission into a dummy
load after a band change or a power level change.

73,
Don W3FPR

On 3/17/2015 4:48 PM, Steve Kavanagh wrote:
> I'm starting to play a bit with JT65 on HF (using WSJT-X) with my K2 and homebrew interface hardware.  The frequency response of the K2 seems reasonably flat, but occasionally I see power dropouts when the tones change.  This is despite always hitting the requested power at any audio frequency using the "tune" button in WSJT-X. It seems to happen less when I have plenty of audio drive - does it make sense that the K2 power control might get a bit confused by switching transients when there is only just enough audio to get the RF output up to the value set with the power knob? For those who are using WSJT modes on the K2 successfully, what ALC readings do you usually run at ? I'm hoping eventually to get the K2 going with transverters for VHF meteor scatter on FSK441 - is the stock OP1 filter wide/flat enough to work well for this mode?  S/N 4509 is the older of my two K2s. Any other hints for using the K2 on WSJT modes? 73,Steve VE3SMA
>


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[Steve Kavanagh]

Thanks for the clear list of ALC-restart cases, Don. I don't think that's what is happening, but I will recheck. That's about the ALC level I was aiming for, but got more stable output with one steady bar or more than one bar. 73,Steve VE3SMA
      From: Don Wilhelm <[hidden email]>
 To: Steve Kavanagh <[hidden email]>; "[hidden email]" <[hidden email]>
 Sent: Tuesday, March 17, 2015 5:42 PM
 Subject: Re: [Elecraft] Audio Levels for WSJT on K2, etc.?
   
Steve,

On the K2 with any data mode, run the audio up until you see one ALC
bar, and then back it down until it just barely goes out.
That is the correct audio level - set the power to the level desired and go.

One thing about the K2 power level is that it is reset after a band
change or a power level change.  That is better than creating a power
spike.  It takes a couple of dits in CW or a few syllables in SSB mode. 
Because your data audio stream is not syllabic, it may take a bit longer
for the K2 to adjust to the proper power level. There is no work-around
that I know of other than doing a "throwaway" transmission into a dummy
load after a band change or a power level change.

73,
Don W3FPR



On 3/17/2015 4:48 PM, Steve Kavanagh wrote:
> I'm starting to play a bit with JT65 on HF (using WSJT-X) with my K2 and homebrew interface hardware.  The frequency response of the K2 seems reasonably flat, but occasionally I see power dropouts when the tones change.  This is despite always hitting the requested power at any audio frequency using the "tune" button in WSJT-X. It seems to happen less when I have plenty of audio drive - does it make sense that the K2 power control might get a bit confused by switching transients when there is only just enough audio to get the RF output up to the value set with the power knob? For those who are using WSJT modes on the K2 successfully, what ALC readings do you usually run at ? I'm hoping eventually to get the K2 going with transverters for VHF meteor scatter on FSK441 - is the stock OP1 filter wide/flat enough to work well for this mode?  S/N 4509 is the older of my two K2s. Any other hints for using the K2 on WSJT modes? 73,Steve VE3SMA
>



 
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