--- In [email protected], "Clive Lorton" <[EMAIL PROTECTED]> wrote:
>
> Could you answer one question please. In Winrad where does the
> S meter normally idle when there is no audio input to the Delta 44? 

 Clive,

  in such case, and with a 500 Hz bandwidth, the S-meter hovers around
S4, which, if referred to an RF signal over 50 ohm system impedance,
would mean about 1.6 uV

 I started Winrad with the SDR-IQ (which doesn't use the sound card,
but sends the data through the USB port) tuned to a quiet region of
the RF spectrum, and the reading was almost the same.

 We should not be misled by the rice boxes (Icom-Yaesu-Kenwood) that
show *NO* reading of the S-meter below a given threshold of the input
signal. With a theoretical -73dBm over 50 ohm for S9, and 6dB per
S-unit, a reading of S1 is about 0.2 uV, which normally is much lower
than the band noise, except perhaps on the 10m band, in a quiet day.

 In a well behaved radio, with a proper S-meter, it should almost
never be at zero, but always flicker around S1 - S2 or more on the
sheer band noise.

73  Alberto  I2PHD


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