WiNRADiO G305 User’s Manual
29
AFC
The Automatic Frequency Control function is activated by pressing
the
AFC
button. It will keep the receiver tuned to the selected
station if the transmitter frequency drifts. While this function is
active, the receiver will periodically check the received signal and correct the
frequency in approximately five-second intervals.
This facility is not
recommended for LSB and USB modes with voice modulation.
RF Gain
The RF Gain (i.e. radio frequency front-end gain of the receiver) can be
adjusted using two controls, the
Attenuator
and
Preamplifier
. Normally, the
Attenuator
should be off, and the
Preamplifier
should be on, for maximum
receiver sensitivity.
Turning the
Attenuator
on reduces the receiver sensitivity by 18 dB (i.e. 6
times), while switching the
Preamplifier
off results in a further reduction by
approx 12 dB.
Attenuator and Preamplifier
Why would you ever need to reduce the sensitivity? Because unusually strong
signals from local stations may occasionally cause overloading. Such
overloading can make the reception worse, and even cause stations to appear
on frequencies, where none exist (
ghost
stations). See
Appendix C -
Dealing
with Interference
for more information on this phenomenon.
If a received signal is too strong, causing overloading, distortion or the
appearance of ghost stations, you should reduce its level by pressing the
Attenuator
button and/or disabling the
Preamp
.
