That is good, Dave, except for receivers that distort heavily when the
AGC is disabled. If you just use manual gain control, and reduce the
gain for strong signals, the effect is the same, only manual. You will
lose the weak station because you have reduced the gain and the
sensitivity. The only way to still copy your weak station and get rid of
the strong one is to filter at IF frequencies, which is what fixed
filters or passband tuning does. IF DSP will do it also these days, but
it needs to be at IF frequencies and not audio frequencies if you are
going to prevent AGC capture by an unwanted stronger signal.
14.101 is adjacent to Pactor activity and if you monitor it long enough,
you will see the Pactor station stop decoding of ROS. However, most of
the automatic Pactor activity we hear is in the US, so the problem may
not be as big on the other side of the big pond.
73 - Skip KH6TY
Dave Ackrill wrote:
KH6TY wrote:
> 2. Pactor signals of 500 Hz width, outside the ROS signal, that capture
> the AGC, do desensitize the receiver and cause loss of decoding, as
> expected. Passband tuning takes care of that problem however.
>
As with many other digital modes, I've been using it with AGC switched
off.
Dave (G0DJA)
