FT-991 review

| noviembre 27, 2014

FT-991 review


Super-Advanced Receiver Circuitry Combined With Intuitive Operation Further Raises the Bar for Compact All Mode Transceivers


New generation FT-991 all-band transceiver offers full-fledged support for all modes

Uncompromising Receiver Circuit Design Ensures Excellent Basic Performance from HF to VHF/UHF

FT-991 receiver block diagram

Sophisticated receiver front end on a par with FTDX Series Transceivers

■Triple conversion with 1st IF frequency of 69.450 MHz for all bands

■ 1st IF stage implements a narrow bandwidth 3 kHz roofing filter as standard equipment

Designed for outstanding adjacent multi signal characteristics, not only in HF but also in VHF and UHF bands.

■Features the highly acclaimed quad mixer of the FTDX series transceivers, along with a dedicated VHF/UHF mixer The 1st IF mixer for HF/50 MHz features a quad mixer with four 3SK294 dual-gate MOS-FET devices that assures extremely low noise, excellent intermodulation characteristics, and high dynamic range. A dedicated VHF/UHF mixer, separate from the HF bands, allows design optimization for targeted frequencies, resulting in superior performance characteristics.

FT-991 review

RF amplifier design is optimized for each band

  • Selectable IPO/AMP 1/AMP2 (HF/50 MHz) settings for optimized operation with any received signal
  • Separate RF amplifiers provide best characteristics for each band

The IPO, AMP1 and AMP2 selections for the HF/50 MHz bands allows matching the settings to the current band and conditions, in order to ensure optimal RF amplifier operation. The RF amplifier for the 430 MHz band uses high-electron-mobility transistor (HEMT) NE3509 devices which maintain good performance also in the GHz range, combining high gain with a low NF (Noise Figure).

FT-991 review

IF DSP from YAESU is Famous for Superb Interference Rejection

Same high-speed floating point DSP as used in FTDX Series

The high speed floating point DSP chip TMS320C6746 (3000 MIPS / 2250 MFLOPS) from Texas Instruments makes possible excellent interference rejection with actual signals under real-world conditions, not only in the HF but also in the VHF and UHF bands.

FT-991 32-bit High Speed floating point DSP

Highly effective interference rejection

The IF WIDTH and IF SHIFT functions that form the basis of removing interfering signals are of course implemented to best effect. The efficacy of interference rejection is further enhanced by sophisticated functions inherited from the FTDX series such as 16-stage digital noise reduction and the DNF (AUTO NOTCH) filter that rapidly tracks even multiple beats. The CONTOUR function that brings the desired signal easily into focus with a natural sound; the NOTCH function with selectable bandwidth, and other functions are provided for comfortable and convenient DX and Contest QSO operation.

FT-991 Digital noise reduction performance

Final Stage with Ample Power Reserves: 100 W for HF/50 MHz Band and 50 W for VHF/UHF Band

High quality push-pull amplifier with 100 watts for HF/50 MHz

Using a push-pull arrangement of RD100HHF MOS-FET devices renowned for excellent performance in the HF/50 MHz range, the amplifier delivers 100 watts of low-distortion, high-quality power.

High speed 1.8 to 54 MHz antenna tuner included as standard equipment

The high speed digital tuner employs relay switching and features a large 100-channel tuning data memory. This allows the user to instantly call up optimum matching conditions for previously used frequencies.

50 W amplifier for VHF/UHF assures plenty of power for high frequency bands

The final amplifier for the VHF and UHF bands uses the high-output MOS-FET RD70HUF2 device which incorporates two MOS-FETs in a single package, providing ample output power of 50 watts.

Latest Touch Panel Operation Combined With Traditional Layout Realizes Optimal Ease of Use

3.5 inch full color touch panel display for convenient comfortable operating

■ Full color TFT LCD display provides useful informatiori about function status and settings at a glance

■ Highly responsive panel with functional design and intuitive layout makes touch operation a pleasure

■ Four user-customizable function keys offer quick access to mode-dependent assignments

■ Traditional layout of Main Dial knob and related controls makes experienced users feel right at home

Advanced Spectrum Scope Function With Waterfall Display Capability

■ High resolution spectrum scope that is not usually found in this class of transceiver, permits instant evaluation of band conditions

■ ASC function automatically switches between the Scope sweep and the receive audio in conjunction with the tuning operation

Support for Advanced C4FM Digital Functions

■ V/D mode for simultaneous transmission of voice and data with powerful error correction optimal for mobile use, and Voice FR (Full Rate) mode for high quality audio transmission

■ AMS function instantly recognizes digital mode or FM mode and enables mutual communication

■ GM (Group Monitor) function allows easy onscreen checking for group members within range

■ 126 types of DSQ (Digital Squelch) enable pinpoint selection of communication stations

* Data FR mode (high speed data communication mode) is not supported therefore image send/receive by C4FM digital is not possible.

Basic function

Versatile Array of Functions for CW Operation

  • Advanced electronic keying (4 to 60 wpm) with FULL BK-EST support
  • Electronic Keyer Weight control (2.5 – 4.5)
  • CW side tone pitch frequency adjustable (300 -1050 Hz)
  • Message Memory function (5 ch x 50 characters)
  • APF function with 3-stage bandwidth selection improves S/N ratio for enhanced intelligibility
  • Auto Zero-in function facilitates subtle tuning operations for CW
  • Automatic «Beacon» keyer mode
  • CW SPOT Feature
  • CW Mode reversal (USB or LSB injection)

Convenient Function for FM Mode

  • 104 types of DCS (Digital Code Squelch)
  • ARS function provides easy repeater access
  • 50-tone CTCSS Encoder/Decoder for FM operation

Other Useful and Convenient Functions

■ Speech Processor

■Parametric MIC EQ «Five-channel digital voice message memory function for repetitive voice messages MULTI dial design facilitates setting operations Full Key button Illumination by White LEDs

■ Independent AF GAIN and RF GAIN, and CLAR/VFO-B knob «FH-2 Remote Control (Optional) «VOX «MOX «99 channel memory (supports memory group view, 12 alphanumeric characters) RTTY/D ATA Jack TUN/LIN connector allows connection of optional VL-1000 or FC-40 Wide Band Receive Capability (30kHz-56MHz, 118-164MHz, 420-470MHz) CS key brings up a preselected menu with a single touch

■ USB port allows connection to a PC with a single cable (CAT control, Audio interface, PTT/SHIFT control) High Stability 0.5 ppm TCXO Carrying Handle «Tilt Stand


RX Frequency Range 0.03 – 56 MHz, 118-164 MHz, 420 – 470 MHz (operating), 1.8-54 MHz, 144 – 148MHz, 430 – 450 MHz (specified performance, Amateur bands only]
TX Frequency Ranges 1.8-54 MHz, 144 – 148MHz, 430 – 450 MHz (Amateur bands only)
Frequency Steps 5 / 10 Hz (SSB, CW, AM), 100 Hz (FM, C4FM)
Power Output 5-100 watts (2 – 25 watts AM carrier)
Modulation Types J3E (SSB): Balanced / A3E (AM): Low-Level (Early Stage) F3E (FM): Variable Reactance / F7W (C4FM): 4-level FSK
Circuit Type SSB/CW/AM: Triple-conversion Super heterodyne FM/C4FM: Double-conversion Super heterodyne
Intermediate Frequencies SSB/CW/AM: 69.450 MHz / 9.000 MHz / 24 kHz FM/C4FM: 69.450 MHz / 450 kHz

Rear Panel

FT-991 Rear Panel

FT-991 User Manual


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