power genius IMD at 2000w

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power genius is rated 2kw output so therefore I would like to know the 3rd and 5th order imd at the 2kw level? What current and voltage does the power supply provide at 2kw output? my estimate is 80 amps (at 52v) will be the minimum requirement for a full 2kw out... anxious to hear the results..
73 VE2AED Howard
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Howard

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Posted 2 months ago

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Bill W2PKY

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20M into perfect load 60 amps @ 47V = 1800 out. 

Not able to measure IMD.
(Edited)
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Matt (K0KB)

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15M perfect load: 56A at 50V for 2kw power out
80M perfect load: 56.3A at 51.9V for 2kw power out.

These are steady carrier (tune function on 6600).

Also not able to measure imd

The amp is such a champ.
(Edited)
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KF4HR

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Just curious.  Does the PG-XL auto limit itself to 1500 watts?
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Matt (K0KB)

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No
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KC2QMA_John

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Sure is nice to have the extra headroom for a very clean signal.
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Bill W2PKY

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20M 1750; 160M 1650 limit all others 2K. They call it automatic power control. APC
The amp has protection monitoring against overdrive and SWR conditions.
(Edited)
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KF4HR

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Nice.
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Howard

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John , How do you know that the signal is very clean ? Have you tried a 2 or 3 tone IMD test? Howard VE2AED
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Howard

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I have heard that the "Power Genius " does not have any antenna tuner , I wonder if I missed this detail . I am attaching a link to an IEEE paper "Output Impedance Mismatch Effects on the Linearity Performance of Digitally Predistorted Power Amplifiers " The paper also covers non predistorted amplifiers and the short story is that any impedance mismatch to the load can degrade linearity simply by the magnitude and phase of the reflected power .  73 de VE2AED link https://www.researchgate.net/publication/270788754_Output_Impedance_Mismatch_Effects_on_the_Linearity_Performance_of_Digitally_Predistorted_Power_Amplifiers
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Bill W2PKY

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The External Tuner is in development, no ETA as of yet.
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Howard

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Bill , it appears that Flex has already begun shipping and as this paper trail indicates this is to be an "external" tuner and is still in development ,thus it appears that the amp will be shipped and the tuner becomes an external option . Thank you es 73 Howard VE2AED
(Edited)
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HCampbell WB4IVF

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The tuner has always been advertised as an external option!  Last I heard, it should be well-integrated with Flex (as Bill stated), and will be offered with an optional remote kit to allow installation at the antenna if so desired.  That would be a great feature in some installations and was one of the reasons given for opting for an external tuner. 

To me the main issue is the long, long wait, which is giving my ATR-30 a new lease on life.  (-:

BTW, no amp that I am aware of has an internal tuner capable of a truly wide matching range at high power.  For that I’d look at an HF-Auto or similar.

Howard/WB4IVF
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Howard

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Howard (2 ) this is Howard (1) there are 2 ldmos amps that I know of that have full power tuners , I have one of each so far KPA1500 and RFkit . 
 Both can tune a full 3:1 in both directions ( 17 - 150Ω ) at 2KW although I don't recommend 2KW , I measure IMD with 2 tone ~ -35Db  at 1.5KW

Howard (1) VE2AED  https://www.qrz.com/lookup/ve2aed

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HCampbell WB4IVF

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Hi Howard1 –

Yes, the internal KPA and external Flex tuners should be capable of handling full power, but at a quite limited 3:1 matching range (the advertised Flex tuner spec is also 2000W @ 3:1 SWR).

As I said, the physically separate Flex tuner can be placed at the amp, or as Flex has stated, at the antenna with an optional remote kit.  In addition to being closely integrated with the Flex radios/amp, to me that is an important feature and I may well take advantage of it.  Some prefer to have the tuner in the same box as the amp, and I can understand that too, but I prefer a separate tuner for the above reason. 

For any of these amps, if a wide matching range at high power is required you’d need a heftier external tuner.  I have not seen any published IMD specs / test results for the Flex amp as of yet.

Howard2

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Howard

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Howard (2) ,
  I hope they test 3rd order  IMD into  15 meter multiples of coax into an antenna with 2:1 SWR and without the antenna tuner ... :)  "on 20 meters"
(Edited)