For Operators With A Common Vision of Design and Value
| 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)* |
 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 |
|
- AC power cable
- Spare fuses
- Speaker plug
- Rackmount handles
- IC-PW1 HF+50
MHz 1 kW LINEAR AMPLIFIER
Covers all HF and 50 MHz bands, provides clean, stable 1kW output. Automatic antenna tuner and compact detachable controller are standard. 2 exciter inputs are available.
SP-20 EXTERNAL SPEAKER - SM-20 DESKTOP
MICROPHONE
Unidirectional, electret microphone for base station operation. [UP/DOWN] switches and a low cut function are available. - CT-17 CI-V LEVEL
CONVERTER
For remote tranceiver control in the jack using a PC equipped with an RS-232C port. - HM-36 HAND
MICROPHONE
Hand microphone with [UP/DOWN] switches
4 audio filters; head phone jack; can connect to 2 tranceivers.
IC-7700
PDF brochure: 2700kb