I don't want any of my energy going outside the filter or coming in from outside. I would swap 1,2 and always do. It probably makes a tenth dB difference altogether but I don't want even that error.
Bob
N4HY
Gerald Youngblood wrote:
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Measuring MDS is a simple procedure on the SDR-1000 with PowerSDR software.
The software calculates the RMS noise power within the 3dB bandwidth of the
filter so you can read it directly on the meter when the radio is connected
to a dummy load. You do have to accurately calibrate the radio with a known
signal source and the image rejection must be properly adjusted.
So do the following:
1) Calibrate the radio with a signal generator
2) Null the image
3) Set the filter bandwidth to 500 Hz
4) Attach a dummy load
5) Set the RX meter to Signal Avg
6) Read the meter and that is your MDS
There is NO AGC in these measurements because they are measured before AGC.
73,
Gerald
--
Laziness is the number one inspiration for ingenuity. Guilty as charged!
