Sinisa wrote,  in part:
> Connecting and disconnecting your antenna should result
> in noise level difference of 10-12 dB (~2 S units).
Since the AGC within the Orion CANNOT be completely
turned OFF,  where should the Threshold be set when
the above test is performed:  high or very low??  Selecting
the AGC OFF with the Orion results in a default   AGC
Threshold of 0.37 uV,  the lowest available setting.
> Anything more than that overloads the receiver unnecessarily.
> Anything less than that reduces the signal to noise ratio.
> 
> Start with full sensitivity and reduce it until the above
> condition is satisfied. 
With the AGC threshold sitting high or low?
> Orion has 3 sensitivity controls
> which should be reduced in the following order:
>   * preamp off;
>   * attenuation increased to 6, 12 or 18 dB;
>   * RF GAIN reduced.
> 
> After this is done, you can adjust AGC THRESHOLD to a suitable
> value,......
[from what value during the above adjutrments?]
> ....which usually means that background noise is comfortably
> audible, but not as strong as usable signals.
73,  Jim KH7M
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