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Icom has been developing radio communication equipment for over forty years. Icom's history has been technical challenge and excellence from the first analog PLL circuit in the IC-200, to the ground-breaking 32-bit floating point DSP of the IC-756PRO. Icom has always given shape to ideas with this technical accumulation. Recent Ham radio stations increasingly use high power and high gain antennas that raise the field strength of unintended signals, and thus require a wider receiver dynamic range. Icom has developed the new flagship model IC-7800 which is a fusion of forty years analog RF circuit development expertise, with cutting edge digital technology.
The result is 110dB dynamic range, +40dB 3rd order intercept point in HF bands and other phenomenal performance features. The receivers combine various current and new technology, to obtain the +40dBm IP3, a specification never before achieved in Ham radio. Quite simply put, the IC-7800 is the ultimate Ham radio. Nothing else comes close!
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Dynamic range characteristics |
Icom's 40 years of analog RF circuit experience combined with cutting edge digital technology results in an astonishing 110dB receiver dynamic range and a +40dBm IP3 in the HF bands. A first in Ham radio! To achieve this superior receiver performance, Icom's engineering team completely reviewed the whole analog circuit and matched it to the DSP units. This allowed us to explore new technical dimensions such as a double conversion super-heterodyne system, mechanical relay BPF switching and two roofing filters.
The IC-7800 uses highly reliable and durable mechanical relays for BPF switching instead of non-linear semi-conductors which cause distortion. The mechanical relay prevents 2nd order distortion at the primary stage of signal processing. The IC-7800 has two roofing filters before the 1st IF amplifier stage. One is 15kHz fileter for FM mode and the other is 6kHz filter for SSB, CW, AM and data modes. The IC-7800 switches between these two roofing filters depending on operating mode. Typically, transceivers use only one broad 15kHz roofing filter for all modes. This is not an optimal design for SSB, CW, or AM modes. The two roofing filters dramatically improve the blocking characteristics from strong adjacent signals.
BPF Unit |
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Two roofing filters |
The pre-selector works from 1.5MHz to 30MHz. The preselector automatically tracks the intended signal, keeping the pre-selectorfs bandwidth centered on the operating frequency at several kHz steps (minimum). The preselector rejects unwanted out of band interference from multi-multi operation or strong broadcast stations, as your first line of defense against interfering signals. The center frequency of the pre-selector is adjustable from the DIGI-SEL tuning knob on the front panel.
Automatic preselector |
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Automatic Preselector Characteristics in 14MHz band |
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While mixers often become a cause of signal distortion and spurious emissions, the IC-7800 utilizes a double conversion super-heterodyne system using a newly developed image rejection mixer. A high performance D-MOS FET array for the 1st mixer stage is infused with a signal from the high-level C/N, high-drive Local Oscillator from the PLL unit. This new mixer reduces signal distortion through IF processing and provides a high-fidelity signal to the DSP unit.
The IC-7800 has two types of AGC loops. One of the AGC loops detects the AGC voltage at the BPF input in the DSP unit and feeds back to the 1st IF amplifier. This AGC loop prevents the saturation of the 1st IF amplifier from strong signals out of the BPF bandwidth, and improves the dynamic range against 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. Combining the digital IF filter, manual notch, and the 1st IF stage, these are all controlled by the DSP unit. 110dB of ultra wide dynamic range in the receiver means the IF amplifier is distortion free from strong signals.
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AGC setting screen |
In addition to the preset AGC time constants (slow, medium and fast), the manual AGC volume provides flexible detailed AGC tuning.
The ultimate dual receiver performance is at your control; the receivers are completely independent all the way from the 4 antenna jacks, through the pre-selectors, DSP, signal detectors, front panel control, and right into the stereo headphone! The dual receiver allows you to receive two different bands simultaneously in different modes, with each receiver not causing any adverse affect to the other one. This true dual receiver takes your band hopping and contesting experience to the next level!
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Filter preset screen |
The digital IF filter has superior filtering performance and a distinguished shaping factor that demonstrates the power of 32-bit floating point DSP. The digital filter is completely free from deterioration due to deviations in band characteristics, temperature change, or mechanical vibration, all of which have likely been seen with analog filters. The digital IF filter also provides excellent ripple characteristics and clean cut that have never been available with analog filters. The filter shape is selectable from soft and sharp, depending on the purpose, operating band, band conditions, etc. It is also possible to set CW and SSB filter characteristics independently, and also select the filter shape while actually receiving a signal.
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Manual Notch (Wide/Middle/Narrow) |
The IC-7800's manual notch filter shape can be set in 3- steps for the various receiving conditions. The manual notch filter has extremely sharp characteristics for processing in the DSP and provides tremendous performance for attenuation levels of more than 70dB in all shapes. The DSP-based manual notch provides stable performance and completely shuts off undesired beat signals without affecting AGC gain. In addition, an automatic notch filter tracks and wipes off the beat signal and RTTY interference.
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32-bit Floating point DSP chip |
The IC-7800 uses four pairs of 32-bit floating point DSP units and 24-bit AD/DA converters. One for the transmitter, one for each receiver, and the final one for the spectrum scope. The DSP units deliver the phenomenal performance of the digital signal processing. A powerful combination born of Icom's analog RF technology and experience.
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PA Unit and large heat sink |
The newly designed push-pull power MOS-FET amplifiers work with 48V DC and provide a powerful 200W of output power at full duty cycle with low IMD in all bands. The digital PSN modulator using a dedicated DSP unit consistently reproduces an outstanding signal-to-noise ratio, providing clean and clear transmission.
Your IC-7800 will be the reference point on the band with a standard stability of + 0.05ppm! Even on the 6m band, that is less than 3Hz error from the Oven Controlled Crystal Oscillator! Also, a 10MHz reference frequency can be the input/output for external equipment.
OCXO Unit |
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Reference input/output connector |
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RTTY Decode screen |
The IC-7800 has a modulator and demodulator for the 2 major HF ham digital modes. Encode and decode of PSK31 and Baudot RTTY signals are possible by simply connecting a USB keyboard to the IC-7800. The twin peak audio filter improves RTTY reception. In addition, transmitted and received messages can be stored to the CF memory card and transferred to your PC.
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Example of spectrum scope centered on the receiving frequency.
Example of fixed spectrum scope range. |
With the dedicated DSP unit, the spectrum scope provides 80dB dynamic range of signal processing (the IC-756PROII is 60dB). The scope span can be set to +2.5 to +250kHz in 7 steps, providing wide band signal analysis.The monitor range can be set independently from the receiving frequency. You can monitor the band condition between the selected sweep edges, as well as sweep a selected band width centered on the receiving frequency in the scope screen.
In addition, the scope has many features including scope attenuator (10dB/20dB/30dB), 3 types of marker (Main band, Sub band, Transmit), Max hold function and Main-Sub band one touch switch. The mini scope function is convenient for continuous monitoring even while adjusting the set mode.
Mini scope screen |
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Scope BPF characteristics |
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Transmit level setting screen.
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The built-in audio equalizer has the separate bass and treble adjustment for a total of 121 combinations, so you can tone your voice up or down as you want. In addition, the transmit bandwidth is selectable from 100, 300, 500Hz at the low-pass edge, and 2500, 2700, 2900Hz at the high-pass edge respectively. 3 types of high and low combinations can be stored in the memory. With this flexibility of DSP based waveform shaping, transmit audio quality is adjustable depending on the operating situation.
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Needle type meter
Bar type meter
Edge width type meter
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Response time, color, resolution, visibility the IC-7800's display has been examined in all aspects, and an active matrix 7-inch (800 400 pixels) TFT color display was selected for the IC-7800. This large display shows main, sub-band frequencies including various settings and operating conditions as well as spectrum scope, S-meter and RTTY/PSK31 decoded messages. The S-meter shows near analog like needle swings that are smooth and accurate. In addition to the 3 styles of digital meter, the IC-7800 has digital multi-function bar graphic meters to show various conditions such as Final PA temperature, PA voltage etc. Further more, the IC-7800 has a VGA connector for an external monitor and an S-meter connector for an external analog S-meter.
While most HF/50MHz transceivers share the preamp between the HF bands and 50MHz band, the IC-7800 uses an exclusive preamp and mixer especially designed for the 50MHz band. This preamp and mixer are tuned to the 50MHz band and improve cross modulation characteristics, particularly important when picking up a very weak signal close to a strong station.
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The Digital Voice Recorder (DVR) is a convenient function for contests, DX-peditions, field day and even normal operation. Record your callsign, CQ, or other station information into a memory. Independent "Record (REC)" and "Play" buttons are on the front panel.
The IC-7800 has a CF card slot and a CF card will be supplied with the IC-7800. You can store your various settings such as filter, display, microphone equalizer, etc, on your card. When sharing the IC-7800 with multiple-users such as on a DX-pedition, in a contest or as a club rig, the CF card allows you to restore your personal settings instantly.
The IC-7800 is equipped with DSP based twin PBT filtering.It provides excellent performance on a completely different level from analog filters. The passband width, shift direction and steps (50Hz) are graphically displayed on the LCD.
The 32-bit floating point DSP has excellent calculation performance, which processes complex and sophisticated algorithms. This allows the DSP to attenuate noise without delay and extracts noise-level signals. It is possible to vary the suppression level in 16 stages.
A newly designed noise blanker provides significant reduction of pulse-type noise. The noise blanker allows the operator to change the threshold level as well as blank time parameter and attenuation level.
When the IF filter passband is reduced to 500Hz or less in SSB mode or SSB-data mode, special band pass filters (BPF) are automatically selected. The BPF automatically sharpens for better rejection of interfering signals like a CW filter. Along with the BPF setting, the IC-7800 enables the 1/4-tuning step function for easier operation.
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Antenna memory setting screen |
The IC-7800 has 4 antenna ports (ANT1 to ANT4) with an automatic antenna selector. Once you program the operating band to the antenna port set mode, the antenna port is automatically selected as you change the operating band. Each antenna port can be set to the antenna usage type such as for Tx/Rx use, Rx only use and off line. The antenna switch button allows you to change an antenna port temporarily.
With the push of a band button, the band stacking register allows you to simply bring back the last three operating settings (including antenna port) per band for simple recall. This function is convenient when you operate 3 modes such as SSB, CW and RTTY on one band.
The IC-7800's memory keyer has 4 channels with 70 characters for CW, 8 channels with 70 characters for RTTY and 8 channels with 70 characters for PSK 31 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.
[Antenna line]
- High speed automatic antenna tuner covers HF and 50MHz bands
- BNC type Rx In/Out connectors for receiver antenna or external attenuator
[Receiver]
- General coverage receiver covers from 30kHz to 60MHz
(* Some frequency bands are not guaranteed., Depends on version.)
- Two types of receive preamplifiers:
Preamp 1; Boost low level signal improving intermodulation characteristics
Preamp 2; Boost low level signal improving receiver gain
- 7-step attenuator (3/6/9/12/18/21dB and OFF)
- Twin peak audio filter for RTTY operation
[Transmitter]
- Low distortion RF speech compressor
- Tx monitor
- 50 CTCSS tone encoder and decoder
- VOX capability (Voice operated transmission)
- All mode power control
[CW]
- DSP controlled CW keying waveform shaping
- Multi-function electronic keyer with adjustable keying speed, dot-dash ratio and paddle polarity
- CW pitch control from 300 to 900Hz
- The normal (default) CW carrier point is selectable from USB and LSB mode.
- Double key jack system
- Full break-in function
- Frequency lock function for split operation
- CW/AM auto tuning function
[Operation]
- Set mode function for flexible and speedy setting
- Memory pad stores up to 5 or 10 operating frequencies
- Quick split function
- Quick dualwatch
- SSB/CW synchronous tuning
- Single knob control from squelch volume to RF gain
- RIT and
 Tx variable up to 9.999kHz
- UTC/Local Clock and timer function
- 1Hz pitch tuning and 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 F scan
- Auto tuning step function
- Dial lock
- Main dial tension control
- Band edge beep
- CI-V interface capability
- Optical digital input/output
- BNC type Transverter connector
- External speaker connectors for main and sub receiver
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