What is so special about '12 dB' SINAD?
Hello Fred,
If you have a calibrated RF signal generator that provides 1 kHz
modulation and an rms voltmeter that covers communication audio
frequencies (say to 3 kHz), then the only thing you need to make SINAD
measurements is a 1 kHz notch filter. You can find schematics for that
in the ARRL handbook and elsewhere.
Good luck!
Chuck
NT3G
Fred McKenzie wrote:
In article , crb wrote:
Is the the input value in dBm on the test equipment the sensitivity of
the receiver at 12 dB SINAD.
The 'at 12 dB SINAD' still gets me.
CRB-
Years ago sensitivity might have been measured using a "20 dB quieting"
method. You would inject an unmodulated carrier and increase its level
until the noise output of the receiver decreased to one tenth of the
no-signal value. This might work for tuning to improve that one
receiver's sensitivity, but it isn't the greatest for comparing different
receivers with different bandwidths.
Isn't SINAD an acronym for "Signal In the presence of Noise And
Distortion"? I don't fully understand how it works, but assume there is a
1 KHz filter feeding one channel that is compared to an un-filtered
channel.
What I want to know is how to build one. Does anyone know of any SINAD
construction articles?
73, Fred, K4DII
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