Utility of Notch on AF-stage ?
 

Hi,

The kenwood TS-570D, according the documentation is equipped with a notch.
Theoretically this is a very useful feature to cancel QRM in the center of a
frequency and be able to listen to weak stations.

But at first sight there no such a NOTCH control on the TS-570D...
Can some one explain me who is right (me or the manufacturer) ?

My explanation is next : is it possible that the notch, even if it is not
provided as an external button on the front panel is in fact well included
(like "built-in") in the AF-stage circuit of this RTX ?
That could explain the fact that it is not very useful in reducing a signal
in the middle of the frequency vs. a model working at the IF-stage.

Your comments are welcome
Thanks in advance

73
Thierry
ON4SKY
http://www.astrosurf.com/lombry/qsl-ts570.htm