Re: QCX+ LOW POWER QUESTION #toroid #40m #alignment #calibration #power


R. Tyson
 

On Fri, Jun 24, 2022 at 03:05 PM, Charles Johnson wrote:
I've done everything short of rewinding L1,2 and 3. I am willing to settle for the 2.3 at this point
Might I suggest following the way Hans tunes up the QCX in the excellent video he produced.
I have built a couple of 40m QCX's and they do not need turns removing from the lpf toroids, assuming they have been wound correctly.
Spreading or compressing the turns, starting with L3 should allow you to bring the output power up.
I personally would not be happy supplying the QCX with 16v I prefer to run equipment at a level that shouldn't stress it. With 30 and 20m QCX's I have left two turns off L3 and that allows tuning for 4 to 5 w out but the 40m QCX tunes up nicely with the recommended number of turns on each toroid. For the difference you see between 12v or 16v supply it isn't going to be measurable by the other guy. I believe you are going to use an amp ? If it is the 50w amp then I find that does make a big difference.

Reg                              G4NFR

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