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On the QMX+, I caution against being too upset if some of the bands have lower power output than others. It's a design of engineering compromises, and not everything is perfect. There are 6 LPFs. Except for 160m and 6m, the other bands all share multiple bands to one LPF. The LPFs are optimized as far as possible; the design has a push-pull PA with very low even harmonic output content, to reduce the requirements on the LPFs. Still there's impedance match to consider and you'll generally find that where a LPF is shared between two (or more) bands, you can play with spreading and squeezing turns, and sometimes you can get a bit of improvement across the board, but you can only get a certain way with it; in the end optimizing one of the shared?bands will impact another.?

There are also software things that can (and will) be done. Right now the PA envelope shaping modulator is run a little further below 12V than you'd like; It's a P-channel MOSFET and could get a lot closer to the input voltage (there isn't a 0.6V drop across the transistor as there would be for a bipolar transistor). The reason it only gets to 90% of max (for example) is because the gain factor of that PA modulator's amplification from the DAC output, and the max DAC value in the firmware, is chosen rather conservatively to take into account component tolerances.?

What I will do in future is implement a self-calibration feature so that the QMX+ can check the PA modulator gain by measurement and then set itself to use more of the full range, get closer to the input voltage in other words. That will increase power output everywhere. It will be best to make a calibration tool which can also REDUCE power output if it's over 5W (or some target value), so for example on 160m run the PA at a lower voltage.?

In this way we should get both higher output power but also more equal power across?the bands.?

Also as always do bear in mind that the difference in watts is what we most think of, but what actually matters for communications purposes is the dB power. A given watts' difference is much less in dB so generally we tend to worry too much about maximizing the output power. S-points are in dB (1S = 6dB) so to gain a 1 S-point advantage you need to multiply by four. For example, from 4 Watts of power to 16 Watts is 1 S-point. From 4 Watts to 5 Watts is under 1dB, less than 1/6th of an S-point... In other words, we should worry less.?