From the RX side of calibration, now over to the TX side.
Per the "Manual Calibration Procedure," I read, "3. Set “TUNE”, Power % to 100." Later steps indicate using 10 watts to calibrate each band. Should the preceding quote indicate '10' rather than '100?' And is that a % or watts? Perhaps there's an as of yet undiscovered by me TX power setting for routine use...
Part two. Whether I set Tune for 10 or 100 it reads '5' or '50' for forward power in the upper right corner of the console. An external meter reads 10 or 100? What gives?
Ref: Page 44 of 24 October 2017 ANAN-7000DLE User Guide. Thetis v2.8.11 on my system.
Manual Calibration Procedure
Re: Manual Calibration Procedure
Don't know what that manual says, but here's the deal: ideally you would set the RF Drive slider in Thetis to 100 and then adjust the calibration factor to get 100W. Then after that, again ideally, if you set the slider to 50 you'd get 50W (or 5W if you are using one of the 10W units like the ANAN-10), 40 = 40, 60 = 60, and so on.
Unfortunately it doesn't work like that. The RF drive slider control in Thetis is HIGHLY non-linear. In other words, if you calibrate it for 100W at slider position 100, you won't necessarily get 10 at 10, 20 at 20, and so on.
To be fair, it's not really Thetis that is at fault (or PowerSDR before that). The software is good, and at the DAC output it is pretty much perfect. It is because the RF amplifier designs from Apache are highly non-linear. That is easily seen if you use PureSignal and look at the AmpView display. It normally shows that very pronounced curve instead of a beautifully straight line.
Therefore you have to choose one of two techniques:
1. Those running without an external amp will probably want to set things up so that 100 = 100 and then take what they get at the lower slider levels.
2. Those running an external amp may wish to optimize performance at a certain power level that equates to full drive on their external amp. For instance my KPA500 generally wants to be driven somewhere between 30 and 40W for full output. I chose to calibrate so that 35 on the slider = 35W out. That way when I make small changes in drive level I can do so more easily and predictably.
Unfortunately it doesn't work like that. The RF drive slider control in Thetis is HIGHLY non-linear. In other words, if you calibrate it for 100W at slider position 100, you won't necessarily get 10 at 10, 20 at 20, and so on.
To be fair, it's not really Thetis that is at fault (or PowerSDR before that). The software is good, and at the DAC output it is pretty much perfect. It is because the RF amplifier designs from Apache are highly non-linear. That is easily seen if you use PureSignal and look at the AmpView display. It normally shows that very pronounced curve instead of a beautifully straight line.
Therefore you have to choose one of two techniques:
1. Those running without an external amp will probably want to set things up so that 100 = 100 and then take what they get at the lower slider levels.
2. Those running an external amp may wish to optimize performance at a certain power level that equates to full drive on their external amp. For instance my KPA500 generally wants to be driven somewhere between 30 and 40W for full output. I chose to calibrate so that 35 on the slider = 35W out. That way when I make small changes in drive level I can do so more easily and predictably.
Re: Manual Calibration Procedure
'Nuther variation on the scheme...
With a dummy load on amp, and without noting the Anan's power out, I adjust the PA settings so that Drive at 100 gives me the maximum amp power out I want on each band.
With a dummy load on amp, and without noting the Anan's power out, I adjust the PA settings so that Drive at 100 gives me the maximum amp power out I want on each band.