Yaesu FTDX-9000D, Руководство по эксплуатации

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Page 9 FT
DX
9000D O
PERATION
M
ANUAL
F
EATURES
Separated Clarifier Display (Page 46, 95)
A clearly-separated display window within the main frequency display area contains receiver and/or transmitter frequency offset ("Clari-
fier") data, for quick comprehension by the operator.
YAESU Custom-designed 32-Bit Floating Point IF DSP (Page 60)
The new IF DSP system, utilizing a TI TMS320C6711 device, is a high-speed 32-bit floating point circuit designed with a unique
objective: to do away with the “digital” sound of many DSP filtering systems, and emulate the “Analog Sound” so familiar and comfort-
able to HF DX and Contest operators. The result is a leading-edge receiver that has the “feel” of a traditional analog receiver, but with
the flexibility and superb filtering capability of a modern digital filtering system.
New Mu (µ) Narrow-bandwidth High-Q RF Filters Using Large-Diameter (28 mm) Coils (Page 64)
On the 14 MHz and lower Amateur bands, Yaesu’s breakthrough “µ-Tuning” RF preselector filters provide the greatest level of RF
protection ever incorporated into an Amateur Radio transceiver. Utilizing a 1.1” (28 mm) ferrite core stack, driven through a coil
structure, µ-Tuning provides greatly improved RF selectivity, even compared to our VRF (Variable RF Filter) preselector, resulting in an
ultra-strong front end. Insertion of the µ-Tuning filter improves the 3rd-Order Intercept Point by at least 4 dB, and you can operate on
a very crowded band with the utmost confidence in your receiver.
VRF (Variable RF Filter) Preselector Filter (Page 66)
On the 18 MHz and higher Amateur bands, and on 1.8 - 50 MHz on the Sub (VFO-B) band, Yaesu’s robust VRF (Variable RF Filter)
preselector provides a relay-selected RF selectivity much tighter than that afforded by traditional bandpass filter networks. Sealed relays
select heavy-duty inductors and capacitors, providing a tracking RF filter that protects the RF amplifier and following stages from strong
out-of-band energy.
First IF 3 kHz Roofing Filter (Page 25, 67)
In the 40 MHz 1st IF, three selectable roofing filters are provided, in bandwidths of 3 kHz, 6 kHz, and 15 kHz, to protect the following
stages from strong signals that could degrade dynamic range in the first IF amplifier and subsequent stages. The roofing filters are
automatically assigned according to the operating mode, but the operator may override the automatic selections on the fly.
CONTOUR Filter Enhances “Analog Feeling” of DSP Filters (Page 25, 68)
The DSP-based Contour system is a unique five-band filter that may be used to roll off or peak the IF response. It is chiefly useful for
modifying the response of the ultra-sharp DSP filters, allowing you to roll off (or emphasize) certain frequency components. Oftentimes,
the result is that a difficult-to-understand signal suddenly will pop out of the background noise as solid copy.
SLOPED AGC Circuitry (Page 76)
I
n traditional AGC systems, all signals rising above a certain RF level are then clamped together at the same audio output, so as to
prevent distortion throughout the IF and AF stages. In the FT
DX
9000D, however, you can engage the “Sloped” AGC capability to
provide an AGC response whereby ever-increasing signal strength results in a slightly-louder audio response, still without accompany-
ing distortion. This lets you use your brain to sort out weak signals from strong ones more effectively.
Receiver AF Limiter Circuit (Page 33, 77)
Occasionally a noise burst or a sudden transmission from a loud station may startle you if you have the AF Gain turned up, and may even
damage your hearing temporarily. The FT
DX
9000D provides an AF Limiter (AFL) circuit which, once engaged, clamps an upper limit
on the available audio output power, much like the AGC circuit does in the RF and IF stages.
“Adjacent Channel Encroachment” S-Meter Monitor (Page 33, 78)
When operating CW in a narrow bandwidth like 300 Hz, you may not be aware of the presence of strong stations that may be making it
difficult for others to hear you. In these situations, the “ACM” (Adjacent Channel Monitor) will take over the Sub Receiver, center it on
the Main Receiver frequency, and display
±
1.2 kHz of signal activity on the Sub Receiver’s S-meter (without feeding the interfering
audio through). This alerts you to the situation, and you can QSY or ask the other station to QSY.
Rugged, High-Output Final Amplifier Design (Page 91)
The final amplifier stage of the FT
DX
9000D utilizes push-pull SD2931 MOS FET devices in a conservative, high-stability design. The
large-area die-cast aluminum heat sink is monitored thermostatically, and a quiet cooling fan will engage when the heat sink temperature
rises during long periods of high-power transmission.
Ultra-linear Class-A Operation Capability (Page 90)
The FT
DX
9000D’s Class-A capability provides ultra-linear amplifier operation at 75 Watts of power output. Typically, 3rd-order IMD
products are suppressed more than 50 dB, while 5th- and higher-order distortion products are at least 70 dB down during Class-A
operation.
Parametric Microphone Equalizer Circuit (Page 88)
F
or unmatched flexibility in tailoring your microphone’s audio to match your voice, Yaesu’s engineers have incorporated the industry’s
first Three-Band Parametric Microphone Equalizer, which allows you to enhance or suppress frequency components in three different
audio bands. Equalization may be applied independently to microphones attached to the front and rear panel microphone jacks.