Changing Receive Bandwidth; Adaptive Filters; Auto Notch (Ssb); Beat Cancel (Ssb/Am) - Kenwood TS-870S Instruction Manual

8 REJECTING INTERFERENCE
CHANGING RECEIVE BANDWIDTH
(CW/FSK/FM)
The width of the receive pass band can be changed
without altering the current receive frequency. Change
the bandwidth by adjusting the LO/WIDTH contrai.
When the control is adjusted, "WIDTH" and the newly
selected bandwidth appear on the Display.
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ADAPTIVE FILTERS
The Auto Notch, Beat Cancel, and Noise Reduction
functions accomplish their design purposes by
modifying the characteristics of adaptive filters.
Adaptive filters adapt or change their characteristics
according to the nature of the signal being received at a
given moment. Menu Na. 18 (TRACK) determines
whether the adaptive filters are allowed to change in this
manner or not.
It is also possible to specify how long the received
signals will be monitored before determining filter
characteristics. This monitor period is inversely
proportional to the response time. The longer the
monitor time, the slower the response time and vice
versa. Use Menu No. 14 (LINE.ENH) to select a
different Line Enhance response time, Menu No. 16
(SP.BEAT) for the Beat Cancel response time, and
Menu No. 17 (SP.NOTCH) for the Auto Notch response
time.
The adaptive filters may not function correctly with
signals that have a poor signal-to-noise (S/N) ratio.
Under poor conditions, you may find that optimum
results are obtained by switching OFF the adaptive
filters via Menu No. 18 (TRACK).
Note: Only Auto Notch, or Beat Cancel, or Noise Reduction can be
used at one time, They cannot be activated at the same time. Also,
Menu No. 18 changes to its default setting when the TS-870S power
is switched OFF and then ON again.
52
AUTO NOTCH (SSB)
After switching ON the function, selecting a mode other
than SSB will switch OFF the Auto Notch function (LED
goes out). Changing back to SSB re-activates the
function automatically (LED Sights). If strong, steady
interference is present, switching Menu No. 18 (TRACK)
to OFF may improve the notching capability. To block
CW interference, switch TRACK to ON, then switch
TRACK to OFF to lock the adaptive filter.
Notch band
band
Press [AUTO NOTCH] to toggle the Auto Notch function
ON or OFF.
« The LED indicator in the button lights when the
function is ON.
Note: The effect af Auto Notch may differ under different receiving
conditions even when using the same response time.
BEAT CANCEL (SSB/AM)
Beat Cancel also attenuates unwanted tones within the
pass band, but it is more capable than Auto Notch at
removing low-level tones. Also, this function works at the
AF level, therefore you will notice there is no S-meter
signal loss, although the S/N ratio may be lowered in the
AM made.
After switching ON the function, selecting a made other
than SSB or AM will switch OFF the Beat Cancel
function (LED goes out). Changing back to SSB or AM
re-activates the function automatically (LED lights).
Interfering
Receive pass band Receive pass band
Press [BEAT CANCEL] to toggle the Beat Cancel
function ON or OFF.
+ The LED indicator in the button lights when the
function is ON.
Note: The effect of Beat Cancel may differ under different receiving
conditions even when using the same response time.