[hpsdr] Mercury phase noise

[FRANCIS CARCIA]

hi All,
I found the 5 MHz reference coming out of my Racal RA6830 about the cleanest in my shack. HP8640B had some spurs out around 20 KHz that was messing up the numbers.
I drove Mercury with about -22 dBM with the preamp on. It was in cw mode with 500 Hz. bandwidth. 500 Hz bandwidth correction factor is -27 dB so it was added to the levels I measured. It looks quite good and didn't notice any difference changing to Penny as a clock source. 
The Final numbers
5.0000 MHz           0dB
4.9999                  -27.3
4.9998                  -33.7
4.9997                  -62.4
4.9996                  -126
4.9995                 -129
4.999                   -139 
4.998                   -141
4.997                   -142
4.995                   -144
4.990                   -145
4.980                   -144
I don't think anyone can complain with these numbers. I need to look at the 8640Bs to make sure there is no BB crud coming out of them causing the noises I heard yesterday measuring dynamic range. My Analog RX would have stripped them out with the roofing filter. I did measure the phase noise with the 8640B set at 5 MHz but as expected the levels were a bit worse. Frank WA1GFZ
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