flex-6300 & dm780

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  • Updated 6 years ago

Hi all, been configuring my new flex 6300 to DM-780 using DAX, everything works as it should with the exception of the power output levels.

power level is set at 25 watts but in order to get this I have to adjust the DAX TX level right up to about 68 thus the level bar indicates that the audio is full scale 0 DB (I am worried about splattering all over the place).

I have gone into the TX levels in the DM780 programme and reduced this from 100% down to 50% but this has made little difference

any help would be good.

73 Keith M1VHT

P.S.  I used the excellent tutorial below to set the DAX up.


Photo of Keith Morrison

Keith Morrison

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Posted 6 years ago

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Photo of Tim - W4TME

Tim - W4TME, Customer Experience Manager

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Set the PA drive to 50 (or greater) and reduce the DAX TX level down until you achieve the power output you want.  If you want to get 25 watts of PEP output with the PA set for 25W, you will have to drive it with a 0 dB input signal.  Increase the PA drive level to give you some headroom to achieve the power output you desire.
Photo of DrTeeth


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The way things seem to work for me is that I use DAX TX to set the drive level - so that one increment more the peak rectangle would go red. I than adjust the power output with the power slider, which seems to be independent of DAX TX. In short DAX TX = drive level, power = power out.

If I use the power slider in WSJT-X, it reduces both the drive and power output.

I'm puzzled, hi hi.
Photo of np2g


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What you really must watch is how much IMD  you are producing. A clean signal is what you desire  not the maximum watts out Process .  

Also A clean signal is not always   derived at that red 0 input  Most of the time less than this indication .

As a illustration :: If you are adjusting  and get say 10 watts clean  or adjusted in such a way that you get 30 watts out the one that works far better is that 10 clean  watts. The rest just irritates the neighborhood.

Tim is very correct in his assessment .