Re: [Elecraft] K3: Still unable to set power correctly in, DATA A(sigh)

2009-01-05 Thread Joe Subich, W4TV
If the onboard meter _thought_ the K3 was making the requested power, that would be one thing. But in this case the onboard meter thinks it's putting out 2x the power, which it is. It depends on what part of the system thinks what. In this case the MCU is reading a given value but

RE: [Elecraft] K3: Still unable to set power correctly in, DATA A(sigh)

2009-01-04 Thread G4LNA
Joe Subich, W4TV-4 wrote: Perhaps the power metering should be derived from a DSP based spectrum analyzer? Accept the fact that the power level control is relative. If Wayne and Lyle can improve on it that's great. However, trying to hold .1 dB or even 1 dB accuracy from 1

Re: [Elecraft] K3: Still unable to set power correctly in, DATA A(sigh)

2009-01-04 Thread Peter Connors, F5VNB
Joe Thank you for pointing out the difficulties in setting average power across a range of modulation types. Whatever the peak/average ratio of the modulation, the output power from the PA is peak limited - so wouldn't the answer be a K3 power meter and power control that shows/sets peak

RE: [Elecraft] K3: Still unable to set power correctly in Data A (sigh)

2009-01-04 Thread Mike Scott
Setting a power control calibrated for CW and expecting that level to be accurate for PSK31 or any other arbitrary digital modulation is complete folly and utter hubris. I also read another post that the K3 watt meter is an average power responding device and there in lies a problem of setting

RE: [Elecraft] K3: Still unable to set power correctly in Data A(sigh)

2009-01-04 Thread Jim Garland
One way to resolve the confusion over interpreting the K3's power output display would be to implement a peak reading/average reading feature, like that in the s-meter. The S-meter can show both peak and average signal strength simultaneously. Perhaps something like that could be done with the

Re: [Elecraft] K3: Still unable to set power correctly in, DATA A(sigh)

2009-01-04 Thread Julian, G4ILO
Peter Connors, F5VNB wrote: Joe Thank you for pointing out the difficulties in setting average power across a range of modulation types. Whatever the peak/average ratio of the modulation, the output power from the PA is peak limited - so wouldn't the answer be a K3 power meter and

RE: [Elecraft] K3: Still unable to set power correctly in DATA A(sigh)

2009-01-04 Thread Joe Subich, W4TV
If what Joe claims is true then this is a more serious issue than even I imagined, since it affects SSB operation as well as data modes. It would be so serious that I suspect he is wrong about it. If I dial up 100W in SSB or data I expect the power to be limited to 100W PEP, not 100W

RE: [Elecraft] K3: Still unable to set power correctly in, DATA A(sigh)

2009-01-04 Thread Joe Subich, W4TV
Whatever the peak/average ratio of the modulation, the output power from the PA is peak limited - so wouldn't the answer be a K3 power meter and power control that shows/sets peak rather than average power? While that might be a solution, it causes other problems. The wattmeter is used

RE: [Elecraft] K3: Still unable to set power correctly in DATA A(sigh)

2009-01-04 Thread AD6XY
Joe Subich, W4TV-4 wrote: Since the K3 power control is based on average power and not instantaneous (absolute) peak power, the power level (both requested and reported) can not be relied on as a gauge of proper operation unless the user knows with certainty how much headroom is

Re: [Elecraft] K3: Still unable to set power correctly in, DATA A(sigh)

2009-01-04 Thread Toby Deinhardt
While that might be a solution, it causes other... Why should the firmware not be able to both? Assuming that there are no hardware limitations, I would think it should fairly easily be possible to do peak readings and average readings as needed by the firmware, in the firmware, for the

RE: [Elecraft] K3: Still unable to set power correctly in DATA A(sigh)

2009-01-04 Thread Julian, G4ILO
AD6XY wrote: Joe Subich, W4TV-4 wrote: Since the K3 power control is based on average power and not instantaneous (absolute) peak power, the power level (both requested and reported) can not be relied on as a gauge of proper operation unless the user knows with certainty how

Re: [Elecraft] K3: Still unable to set power correctly in, DATA A(sigh)

2009-01-04 Thread G4LNA
Peter Connors, F5VNB wrote: To assert that every K3 owner needs an oscilliscope or laboratory grade peak reading meter in order to ensure that they never exceed a given peak power because the K3 internal circuits are incapable of doing so is a very serious criticism indeed. I'm not

Re: [Elecraft] K3: Still unable to set power correctly in, DATA A(sigh)

2009-01-04 Thread Julian, G4ILO
G4LNA wrote: I'm not asserting anything, what I said applies to any rig you care to mention, I don't believe meters. No matter what magic wizardry circuits or software is contained in the rig to deceive to meter into reading power, you can't beat seeing the peak power reading on an

Re: [Elecraft] K3: Still unable to set power correctly in DATA A (sigh)

2009-01-03 Thread Stephen Prior
I can report the identical problem to that which Julian describes. I don't remember the firmware version where this started but it was certainly not always the case that the actual power output in Data A mode was so much greater than the requested power. I can set for 5W and get a displayed (K3

RE: [Elecraft] K3: Still unable to set power correctly in DATA A(sigh)

2009-01-03 Thread Joe Subich, W4TV
I can report the identical problem to that which Julian describes. I don't remember the firmware version where this started but it was certainly not always the case that the actual power output in Data A mode was so much greater than the requested power. I can set for 5W and get a

Re: [Elecraft] K3: Still unable to set power correctly in DATA A(sigh)

2009-01-03 Thread Stephen Prior
So? Reduce the power you request to get the required output. What other radio has a calibrated power output control? The wattmeter in the K3 is relative ... there is a documented power vs. frequency slope. Testing seems to indicate there are also nonlinearities with changes in peak to

Re: [Elecraft] K3: Still unable to set power correctly in DATA A (sigh)

2009-01-03 Thread Leigh L. Klotz, Jr WA5ZNU
There's a thread on a related topic (PSK TX IMD) on the Elecraft K3 list at Yahoo Groups. Rich VE3KI posted some measurements done with the PSKMeter that show poor IMD above about 50W. I've suggested he re-run the tests with a 3dB pad to compare apples-to-apples and reduce the effect of

RE: [Elecraft] K3: Still unable to set power correctly in DATA A(sigh)

2009-01-03 Thread Julian, G4ILO
Joe Subich, W4TV-4 wrote: So? Reduce the power you request to get the required output. What other radio has a calibrated power output control? If you want a bloody laboratory grade meter, buy a laboratory grade power meter. Er, my K2 has always been able to do this. My FT-817

Re: [Elecraft] K3: Still unable to set power correctly in DATA A (sigh)

2009-01-03 Thread Julian, G4ILO
Leigh L. Klotz Jr WA5ZNU wrote: There's a thread on a related topic (PSK TX IMD) on the Elecraft K3 list at Yahoo Groups. Rich VE3KI posted some measurements done with the PSKMeter that show poor IMD above about 50W. I've suggested he re-run the tests with a 3dB pad to compare

RE: [Elecraft] K3: Still unable to set power correctly in, DATA A(sigh)

2009-01-03 Thread Joe Subich, W4TV
The point is it was providing the correct power output levels before the last couple of firmware revisions. Something changed that made it go from putting out approximately the right power level, to putting out WAY TOO MUCH (i.e. causing splatter) power. Not true ... in spite of

RE: [Elecraft] K3: Still unable to set power correctly in DATA A(sigh)

2009-01-03 Thread Joe Subich, W4TV
Rich VE3KI posted some measurements done with the PSKMeter that show poor IMD above about 50W. The K3 wattmeter is essentially an average responding device. PSK31 has a relatively high peak to average ratio ... as much as 6 dB or more depending on the particular data but generally running