Icom's basic idea about the best receiver circuit is to reproduce high fidelity audio without internal distortion. Our answer to achieve this goal is to adopt a double conversion superheterodyne system*. The double conversion system simplifies the electronic circuitry and reduces the number of components which cause internal distortion. The digital signal processing (DSP) technologies and image rejection mixer make it possible to adopt this system.* A triple conversion system is used for the 1200MHz band.
As seen in the above figure, the IC-9100 has 3 independent receiver circuits from the antenna connector to the second IF mixer (image rejection mixer). One each for HF/50MHz, 144MHz, 430/440MHz bands. See the table below for simultaneous receive pairs.
The heart of the IC-9100 is the proven combination of the 32-bit floating point DSP and 24-bit AD/DA converters. This powerful combination supports many digital processing features.
Digital IF filters, manual notch filter and other digital functions are incorporated in the AGC loop management controlled by the DSP unit. The AGC effectively works for the desired signal and rejects blocking by strong adjacent signals out of the filter passband. The AGC time constant presets (slow, medium and fast) give the flexibility and speed needed for working pile-ups.
The IC-9100 DSP allows you to “build your own” digital IF filter. You can quickly choose bandwidth, shape factor, and center frequency, so that you can work that rare DX station. Three filter memories allow you to change filter settings instantly, a great help during contesting or other tough conditions.
Passband width range
|SSB, SSB-D, CW||50Hz–500Hz (50Hz step), 600Hz–3600Hz (100Hz step)|
|RTTY||50Hz–500Hz (50Hz step), 600Hz–2700Hz (100Hz step)|
|AM, AM-D||200Hz–10.0kHz (200Hz step)|
|FM, FM-D, DV*||15kHz, 10kHz, 7.0kHz (Fixed)|
After “building your own” digital IF filter, you can use the digital twin Passband Tuning (PBT) to shift and narrow the IF passband until the interference is gone and you can clearly hear that weak signal.
The 16-step variable noise reduction can significantly enhance the receiver's signal-to-noise ratio, giving you a clean, clear audio signal that may make the difference between making the contact or not.
The digital noise blanker reduces interference from pulse-type noise such as engine ignition. The noise blanker allows you to change the threshold level as well as blank duration parameter and attenuation level.
The digital RF speech compressor boosts average talk power, improving signal strength and readability in SSB mode. It is useful for for breaking through the noise and complete the QSO.
The transmit bandwidth is selectable from 100, 200, 300, 500Hz at the low-pass 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.
The IC-9100 uses high efficiency power amplifiers and large heat sink providing stable output power, even during long periods of operation.
Using receiver design techniques introduced in Icom’s highest grade HF transceivers, the IC-9100 has an IP3 of +30dBm (typ.) in 14MHz band.
Even a weak signal adjacent to st rong signals is clear ly received by the IC-9100.
The IC-9100 comes with a built-in 15kHz 1st IF filter and can accept up to two optional filters (3kHz FL-431 and 6kHz FL-430). By changing the first IF filter width according to the operating mode, the desired signal is protected from adjacent inband signals at the later stages for better receiver performance.
The built-in RTTY demodulator and decoder allow you to instantly read an RTTY message on the display. No external units or PC required. The built-in tuning indicator visually helps in critical tuning.
All of the following CW capabilities are included in the IC-9100:
The internal antenna tuner automatically tunes for low SWR in the HF and 50MHz bands. Once you transmit on a frequency, the tuner can instantly retune the frequency using its built-in memory.
The manual notch filter controlled by the DSP has extremely sharp characteristics and provides more than 70dB of attenuation. It eliminates persistent beat tones without affecting the AGC loop function. The automatic notch filter tracks and eliminates two or more interfering signals, such as beat signals and carriers or tones from digital signals.
The large multi-function LCD displays frequency, 9-character channel name, channel number, multi functional meter (includes S-meter, RF output, SWR and ALC level) for both the main and sub bands vertically. The dot-matrix portion of the LCD shows the following items:
The IC-9100 has a standard type B USB connector and can be connected to a PC. Modulation input, audio output, RTTY demodulator output and CI-V command can be controlled via the USB cable. Also, the conventional CI-V remote control jack is built in to the IC-9100.
When used with the optional CS-9100 programming software, memory channels, band edges, repeater list for DR mode, D-STAR callsign and GPS memory channels can be easily edited with a PC. A USB cable is required for PC connection.
The optional RS-BA1 allows you to use the IC-9100 from another room using your home network, or even from a remote location over the Internet. The RS-BA1 has low voice latency.
The IC-9100 provides excellent receiver sensitivity in the VHF/UHF bands, equivalent to the highly-acclaimed previous VHF/UHF dedicated model, the IC-910H. The IF DSP greatly improves intermodulation and noise elimination and offers better readability than the IC-910H.
By installing the optional UX-9100 1200MHz band unit, you can be operational on the 1200MHz band immediately. The IC-9100 fully covers the HF/50, 144, 430/440 and 1200MHz amateur bands in multiple modes.
The satellite mode synchronizes the uplink (transmitting) and downlink (receiving) frequencies, and tracks the frequencies in the same tuning step. This function matches both normal and reverse mode satellites. Compensation of the Doppler effect can be performed easily. 20 satellite memory channels store frequencies, mode and tone settings for quick set-up.
The optional UT-121 provides D-STAR DV mode digital voice and low speed data communication. Linking of D-STAR repeaters over the Internet allows you to communicate virtually anywhere. In addition to 144MHz, 430/440MH and 1200MHz band, the D-STAR DV mode can be used in 28MHz and 50MHz band simplex mode.
* Digital Smart Technology for Amateur Radio