IC-7700

Taking the Excitement of the Chase to New Heights

Better than +110dBm 2nd order intercept point (IP2)
An IP2 point of more than +110 dBm* means the 2nd order distortion from strong broadcast stations will be completely eliminated. The endless pursuit of leading analog circuit engineering makes it possible to achieve this leading edge level of performance.
* Measurements were made using custom equipment, due to the limits of normal signal generators (SG) and duplexers to +85 dBm. The IP2 figure is a typical value.

Double conversion superheterodyne system
While multiple IF stages can become a source of distortion products and spurious responses, the IC-7700 utilizes Icom’s original image-rejection mixers in a simple double conversion superheterodyne. This reduces distortion and produces a much cleaner audio signal compared to triple or quadruple superheterodyne receivers.

High specification inband IMD
In-band IMD (Intermodulation Distortion) creates undesired spurious signals as a consequence of non-linear processing of multiple signals. All (2nd, 3rd or even higher) orders of IMD performance are superior in the IC-7700. The improvement will be especially evident in CW mode. You’ll notice the difference as you copy weak signals without internal distortion or noise.

Inband IMD characteristics Band pass filter
While some may lead you to believe that coils and capacitors are all created equal, at Icom we know design excellence. Rather than using switching diodes that can introduce distortion, the IC-7700 design utilizes high-grade mechanical relays along with large capacitors and toroidal coils; resistant to magnetic saturation, providing superior linearity, and greatly reducing distortion.

DIGI-SEL (Digital pre-selector)
The DIGI-SEL (digital pre-selector) is a very narrow, user adjustable, pass band filter designed to automatically track the operating frequency, attenuating interference from out-of-band signals. While the pre-selector’s pass-band remains centered on the operating frequency, on the fly adjustments are possible via front panel controls. The DIGI-SEL is especially useful for multi-transmitter operation and near strong broadcast stations by reducing the 2nd, 3rd, and even higher order IMD components from other stations.

High stability OCXO unit Frequency control of the IC-7700 is maintained by the high stability Oven Controlled Crystal Oscillator. The OCXO achieves frequency stability of ±0.05ppm across the specified temperature range, meaning that the frequency will deviate only 5Hz out of every 100 MHz! This specification is equivalent to that of specialized measuring equipment such as signal generators or spectrum analyzers. Also, a 10MHz reference signal can be input to the IC-7700 or output for use by external equipment.

Pre-amplifiers The IC-7700 has a total of 4 pre-amplifiers, two for the HF bands and two for the 50MHz band. The purpose of pre-amplifiers is to improve receiver sensitivity for the pursuit of higher gain and a better noise figure. The IC-7700 employs a noiseless feedback design with pushpull amplifiers. Using feedback transformers, the pre-amplifiers provide a high IP3 while keeping a low noise figure.

1st mixer
The 1st mixer stage is driven with a signal from the high-drive Local Oscillator with excellent C/N. A 16V p-p of high-level LO signal is applied to the mixer to improve intermodulation characteristics while avoiding a parasitic oscillation or noise.

Three Hi-Spec 1st IF filters (Roofing Filter)*1
The IC-7700 employs three Hi-Spec 1st IF filters (roofing filters) of 15kHz, 6kHz and 3kHz before the 1st IF amplifier. Icom ordered special customized high specification devices to improve IMD and achieve better impedance characteristics. As a result, the 3kHz 1st IF filter provides approximately 134dB*2 of blocking dynamic range and allows you to pull out a weak signal in the presence of strong adjacent signals.
*1 Icom calls the roofing filters “Hi-spec 1st IF filters”, because their performance is much better than regular IF filters. *2 At 14.1MHz receive, with 5kHz separation of interference signal.

2nd-stage image rejection mixer
The 2nd-stage image rejection mixer processes signals to reject spurious image responses. In conjunction with the Hi-spec 1st IF filters (roofing filters), image rejection of greater than 100dB is realized. The analog image rejection mixer’s linearity makes it possible to use a simplified receiver design. This improves the distortion performance of the receiver.

50MHz band preamplifier and mixer
The IC-7700 was designed with the 6m aficionado in mind. Rather than sharing circuits used for HF, a separate preamplifier and mixer was designed especially for 6m. This greatly improves the receiver sensitivity by reducing intermodulation characteristics, enabling weak signal works without distortion or interference from strong signals in the band.

Two AGC Loops
The IC-7700 has two AGC loops. The AGC voltages detected in front of and behind the digital IF filter in the DSP unit. The first AGC loop prevents the saturation of the 1st IF amplifier from strong signals outside the pass-band filter, and improves the dynamic range in the presence of strong adjacent signals. The other AGC loop detects the AGC voltage at the digital IF filter output which has only passed the intended signal and draws the full potential from the digital IF filter. The IC-7700 accommodates both the “on-the-fly” operator as well as the most avid “tweaker” operator by providing tunable AGC preset and manual AGC level controls. The AGC time constants can be set in the 3 presets (slow, medium and fast), adjustable from 0.1–6 sec. (0.3–8 sec. in AM) delay. Then the addition of the AGC VR control enables the user to “tweak” or fine tune the AGC reaction time.

Mechanical Relays Mechanical relays using gold contacts have excellent deterioration resistance and superior conductivity.
Hi-spec 1st IF filter The IC-7700 uses custom made Hi-spec 1st IF filters (roofing filters), selected especially for excellent IMD characteristics.
Large Coils To reduce secondary distortion, large coils and capacitors are used in the high-amplitude filter switching circuits. The use of non-linear semiconductors is minimized.
DSP The transmitter and receiver use a 32-bit floating point DSP, offering the high performance of 1800 MFLOPS processing. Also, the spectrum scope DSP achieves 1200 MFLOPS of peak performance.
Power Amplifiers The power amplifiers use a combination of push-pull final with two MRF150 transistors, having proven reliability in ultra professional communications. These devices generate a stable 200W of output power from HF to 54MHz

200W output power at full duty cycle, full power operation
The IC-7700 uses two MRF150 power amplifiers connected in push-pull configuration. The power amplifiers provide a reliable 200W of output power up to 54MHz.

The effective quad cooling fan system ( left photo) makes it possible to generate 200W full power output even during full duty cycle operation. The digital PSN modulator using a DSP unit consistently reproduces an outstanding signal-to-noise ratio, providing clean and clear transmission.

The PA amplifier uses a 48V DC supply to provide output power with low IMD on all bands.

Microphone equalizer and adjustable transmit bandwidth
The built-in audio equalizer has separate bass and treble adjustments for a total of 121 combinations, so you can adjust the tonal quality of your voice as your want. In addition, the transmit bandwidth is selectable from 100, 200, 300, 500Hz at the lowpass edge, and 2500, 2700, 2800, 2900Hz at the high-pass edge, respectively. Three types of high and low combinations can be stored in the memory as favorite settings. With this flexibility of DSP-based waveform shaping, transmit audio quality is adjustable to your preference.

High speed automatic antenna tuner covering HF to 50MHz band
The high speed automatic antenna tuner automatically performs tuning operations and memorizes the setting in 100kHz steps. Once the tuner memorizes the setting depending on frequency, the tuner recalls the setting and matches the antenna instantly. In addition, high-voltage parts allow you reliable, continuous 200W operation even at high duty cycles.

Memory keyer
The IC-7700’s memory keyer has 4 channels with 55 characters for CW, 8 channels with 70 characters for RTTY and 8 channels with 70 characters for PSK31 operation. The memory keyer is convenient for programming station information, calling CQ and call sign for a DX-pedition or contest. Also, the CW memory keyer has other time saving functions such as automatic repeat, serial contest number auto-counter, and Morse cut number functions.

Other Outstanding Features

• BNC type RX IN/OUT connectors for receiver antenna or external attenuator
• General coverage receiver covers from 30kHz to 60MHz
  (* Some frequency bands are not guaranteed, depending on version)
• 4-step attenuator (6/12/18dB and OFF)
• Twin peak audio filter for RTTY operation
• Low distortion RF speech compressor
• Tx monitor
• 50 CTCSS tone encoder and decoder
• All mode power control
• VOX capability (Voice operated transmission)
• Multi-function electronic keyer with adjustable keying speed, dot-dash ratio and paddle polarity and bug key function
• DSP controlled CW keying waveform shaping
• Frequency lock function for split operation
• The normal (default) CW carrier point is selectable from USB and LSB
• APF (audio peak filter) function with soft/sharp filter shape
• Double key jack system
• Full break-in function
• CW pitch control from 300 to 900Hz • CW/AM auto tuning function
• Set mode function for flexible and speedy setting
• Memory pad stores up to 10 (or 5) operating frequencies
• Quick split function enables split operation with a single action
• SSB/CW synchronous tuning
• Single knob control from squelch volume to RF gain
• RIT and Tx variable up to ±9.999kHz
• 20dB attenuator
• Quick RIT/TX clear function
• UTC/Local Clock and timer function
• 1Hz pitch tuning and 1Hz indication
• 101 memory channels with 10-character comment
• Built-in voice synthesizer announces operating frequency, mode and receiving signal strength
• Programmed scan, memory scan, select memory scan, VSC scan and IF scan
• Auto tuning step function
• Band edge beep
• Main dial tension control and dial lock
• CI-V interface capability and RS-232C connector for PC connection
• BNC type Transverter connector
• Triple band stacking register
• FFT scope wave averaging function
• Screen saver function

Rear View