[Elecraft] K3 & ADAT ADT-200A by HB9CBU

[Nico Palermo]

Bill,
the phase noise of Perseus is as follow:

Offset      (kHz)      2    5     10    20   >50
Phase Noise (dBc/Hz)  -141 -145  -148  -151  <-155

As a picture is worth one thousand words, see here for more:

http://microtelecom.it/perseus/tests/Perseus-phasenoise.jpg

To make the test, the phase noise of the source generator,
a homebrew crystal oscillator, has been neglected and it has been assumed
that all the phase noise was due to the receiver oscillator, which is a
crystal
oscillator too.

A more realistic assumption is that the two oscillators, the source
generator
and the receiver LO, are contributing equally to the phase noise figure and
in this
case the performance of the receiver would be even 3 dB better.
The figures indicated are thus worst case values.

For offsets larger than 50 kHz the phase noise performance cannot be really
measured as the prevailing source of noise is of thermal origin and the
noise induced by the reciprocal mixing is below the receiver thermal noise
floor.

Now that you can compare the full table, it would be not difficult for you
to conclude
that even at 1 MHz offset, the blocking dynamic range of Perseus is greater
than
that of your receiver.


73
Nico Palermo, IV3NWV


>Would you tell us how Perseus compares in the following phase noise
>performance?

>The following table is from a post by Eric WA6HHQ in September 2007.  I've
>added the Flex 5000 based on measurements published after Eric's note:

>http://mailman.qth.net/pipermail/elecraft/2007-September/073931.html

>"Here are transmit composite phase noise numbers from the Lab for the K3.
>Needless to say, we are pleased with the results. :-) I've also included
>some numbers from the ARRL reviews for several late model rigs.

>Rig     1kHz    2   10   20   50   100   1M
>K3      -110  -119 -136 -140 -143 -144  -150
>IC7800  -103  -112 -130 -138 -140 -140  -140
>FT2000  -102  -105 -128 -129 -128 -128  -128
>ORION 2 -121  -129 -126 -125 -118 -128  -138
>OMNI 7  -102  -103 -120 -123 -127 -129  -126"
>F5000   -123 (same at all spacings de W4ZV)
>Perseus   ?

>
>
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