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Page 64

9000MP O

PERATION

ANUAL

ECEIVER

PERATION

(

RONT

LOCK

IAGRAM

)

The

9000MP

includes a wide range of special features to suppress the many types of interference that may be

encountered on the HF bands. However, real world interference conditions are constantly changing, so optimum setting of
the controls is somewhat of an art, requiring familiarity with the types of interference and the subtle effects of some of the
controls. Therefore, the following information is provided as a general guideline for typical situations, and a starting point
for your own experimentation.

The

9000MP

’s interference-fighting circuitry begins in its “RF” stages, and continues throughout the entire receiver

section.

9000MP

allows configuration of the features described below independently on the Main band (VFO-A)

and Sub band (VFO-B).

VRF (See page 68)

On the all Amateur bands on the Main (VFO-A) and Sub (VFO-
B) receiver, Yaesu’s powerful VRF (Variable RF Filter)
preselector circuit brovides excellent suppression of out-of-band
interference, with a passband much narrower than that provided
by traditional fixed bandpass filters.

R. FLT (IF Roofing Filters) (See page 69)

Three automatically-selected Roofing filters, in bandwidths of
15 kHz, 6 kHz, and 3 kHz, are provided in the 40 MHz First IF,
right after the first mixer. These filters provide narrow-band se-
lectivity to protect the following IF and DSP stages, and the
filters’ automatically-selected bandwidths may be manually
changed by the operator, if desired, for special operating cir-
cumstances.

CONTOUR Filter (See page 70)

The Contour filter is a unique capability of the

9000MP

providing either nulling or peaking of tunable segments of the
receiver passband, so as to suppress interference or excessive
frequency components on an incoming signal, or to peak those
tunable frequency segments. The amount of nulling/peaking, and
the bandwidth over which it is applied, are adjustable via the
Menu.

IF SHIFT (See page 72)

The passband center frequency response of the IF DSP filtering
may be adjusted using this control.

IF WIDTH (See page 73)

The width of the IF DSP filtering may be carried using this con-
trol.

IF NOTCH (See page 75)

The IF Notch filter is a high-Q notch filter that can significantly
reduce, if not eliminate, an interfering carrier. The Q (sharp-
ness) of the filter may be adjusted using the Menu, and the exact
tuning of the filter may be monitored visually using the Audio
Scope page (especially useful is the “Waterfall” display) on the
External display (not supplied).

DNR (Digital Noise Reduction) (See page 76)

The DSP’s Digital Noise Reduction (DNR) feature utilizes six-
teen different mathematical algorithms to analyze and suppress
different noise profiles encountered on the HF/50 MHz bands.
Choose the selection that provides the best noise suppression,
which concurrently will allow the signal to rise up out of the
noise.

DNF (Digital Notch filter) (See page 78)

When multiple interfering carriers are encountered during re-
ception, the Digital Notch Filter can significantly reduce the level
of these signals.

AGC (See page 80)

The AGC system is highly adaptable to changing signal and fad-
ing characteristics, making reception possible under the most
difficult conditions.

SLOPED AGC (See page 81)

The Sloped AGC system, instead of clamping a fixed upper bound
on audio output across a wide range of input signals, actually
allows the audio output to rise, very gently, with ever-increasing
signal strength. This capability allows you to separate signals,
using your brain, according to signal strength in addition to slight
frequency differences.

IF Filter Quality Adjustment (See page 156)

The “Q” (quality factor) of the IF DSP filters may be adjusted
independently for the Main (VFO-A) and Sub (VFO-B) receiver
IF DSP filters, using the Menu.

Variable IF Filter Shape Factor (See page 156)

You may adjust the shape factor of the Main (VFO-A) and Sub
(VFO-B) receiver IF DSP filters, using the Menu.

CCCCC

ONVENIENT

F F F F F

EATURES

TURES

ROOFING

FILTER

ROOFING

FILTER

ANT