[Elecraft] Issue Resolved K3 Voltage on TX

[Bill W4ZV]

If you operate SSB, you might want to run higher voltage at the K3 terminals
(e.g. at 14.5V which is below the 15.0V spec) to minimize IMD.  This was
discussed extensively in 2009 but the following by W4TV is a good summary:

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> Is there something critical in the radio that 
> gives this outcome? Critical adjustment perhaps? 
> Is it very sensitive what PS we use (ala W4ZV)? 

Yes, it is very sensitive to power supply voltage. 
Look at any of the application notes - the one 
Craig mentions for the P-P RD100HHF FETs is a 
good example.  Decreasing Vcc (or Vdd) by just
one Volt will increase the IMD at 100 Watts by 
10 dB and decrease the maximum output power by 
almost 20 Watts.   

Running the power supply at 14.0 - 14.5 Volts and 
using a power supply with good dynamic regulation 
will go a long way to keeping the K3 "clean." 
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