[K3] [Elecraft] in-band-IMD test

[Alexander Ponomarenko]

Barry N1EU wrote:
> Alexander Ponomarenko-5 wrote:
>   
>> yes PHONES-OUT on front panel(!!!) is different from rear panel PHONES 
>> or LINE OUT outs.
>>
>> The plots from front-panel phones-out is better, but IMD spikes are
>> present.
>>
>> plot withoot S9 signal: http://forum.cqham.ru/download.php?id=32055
>> S9   PRE On    AGC Off: http://forum.cqham.ru/download.php?id=32057
>> S9   PRE On    AGC SLOW: http://forum.cqham.ru/download.php?id=32056
> Thanks for running the test again Alex!
>
> First off, is this really IMD we're looking at?  Aren't you injecting a
> single signal?  Isn't this harmonic distortion, not IMD?
>
> Looking at the s9 agc off pre on plot, the worst "distortion" product is
> still >60dB down.  It would be nice if we saw zero distortion products, but
> I suspect that the distortion seen here is completely inaudible.
>
> 73,
> Barry N1EU
>   
Barry,

now I have only one-tone generator XG1 with S3 and S9 level.
But in my first message you can to see TWO-TONE in-band IMD
results for ic7800, ic756pro2, Flex-5k and K3 for S9 and S9+50 levels.
For all these Radios was used same measure-method on one table.
And of course AF-out for all it was from PHONES-out on FP.

s9+50 AGC-Fast PRE-On http://forum.cqham.ru/download.php?id=32004
s9 AGC-Fast PRE-On http://forum.cqham.ru/download.php?id=32004

These results from Alex UR0ID. The FireBox sound-card are no been 
overloaded.
But hope I get two-tone generator from Alex, and also check my K3 for 
two-tone IMD.

Alex de UR5LAM