[Premium-Rx] Clean LOs

[Clemens Paul]

Hi,

The HP8640B is extremely sensitive to variations in load impedance
also with respect to intermodulation.
Reflected signals up to 60 dB down cause internal intermodulation.
Therefore it's not possible to measure receiver IP3's of more than say +25dBm
even with the best combiners (tunable, with ~60dB return loss) with a
pair of HP8640B.

73
Clemens
DL4RAJ

 
> The 8640 has fairly low phase noise but is not the best especially if
> the load impedance is varied and the output division ratio is not very
> large.
> 
> 73 Brian
> 
> KF6C/G3ZVC