Introduced with the IC-7300, Icom’s RF Direct Sampling System has made SDR performance affordable. Direct Sampling means incoming RF signals are digitized by the Analog-to-Digital Converter and immediately processed by the FPGA (Field-Programmable Gate Array). This process greatly reduces distortion that naturally occurs in the various mixer stages found in traditional superhetrodyne receivers.
The RF Direct Sampling System in the IC-7610 is capable of 110 dB RMDR. This performance gives you the ability to pull weak signals out of the noise of strong adjacent signals. There is a difference you can actually hear as the desired signal comes out of the pileup!
* Representative value at 2 kHz frequency separation (Received frequency: 14.2 MHz, Mode: CW, IF BW: 500 Hz)
Reducing phase noise in a receiver is always a challenge as it is a natural characteristic of a receiver. The master clock of the IC-7610 utilizes a low phase noise VCXO (Voltage Controlled Crystal Oscillator), combined with Icom’s years of technical expertise to design a common power supply for the VCXO and FPGA, yielding an ultra-low phase noise. Also, a 10 MHz reference signal can be input to the IC-7610 for higher precision.
Whether listening to both sides of a rare DX station running split, or looking for a multiplier on a different band or mode, the dual receivers in the IC-7610 have you covered. Two separate DIGI-SEL preselectors, two separate Band Pass Filter networks, feed two separate A/D converters into the FPGA.
The DIGI-SEL preselectors are RF filters with sharp, narrow passband characteristics preventing Analog-to-Digital Converter overflow from large out-of-band signals when sampling the RF signals. Additionally the third and higher order IMD components are reduced. This is ideal when strong signals are received in a contest pile-up or from broadcast stations on adjacent frequencies or bands.
To finish out the receiver, is an internal speaker cabinet. The cabinet is tuned to reproduce clear, natural sounding audio, and is insulated from the radio chassis to prevent noise from vibration and panel resonance.
Breaking with the tradition of mixing a carrier signal with a local oscillator, a Digital-Up-Conversion (DUC) method is used to generate the required signal from the Digital-to-Analog Converter. The chart to the right shows the difference made by this new design.
The built-in automatic antenna tuner memorizes its settings based on your transmit frequency, so that it can recall the tuning setting when you switch operating bands. The emergency tuner function* enables you to operate for short periods of time with an antenna with a high SWR.
* Output power not guaranteed and power may be reduced.
The large 7-inch color display shows various operating and setting information at a glance in high resolution (800 × 480 pixels.) The display clearly shows various features, for example the dual spectrum scope aligned vertically or horizontally, simulated analog meters and RTTY, PSK31/63 mode decoded messages.
The IC-7610 provides dual reception, on different bands, as does the high-speed, high-resolution spectrum scopes. Whether watching for a band opening, working a rare DX station operating split, or searching for a multiplier, the ability to watch each receiver separately allows the operator to concentrate on pulling in a weak signal. The scopes provide class-leading performance in resolution, sweep speed and a 100 dB dynamic range. Scroll mode automatically keeps the operating signal within the scope range. To navigate around the band easier, connect a PC mouse to the USB port for point and click tuning of the receivers.
The Audio Scope screen shows both a FFT scope with waterfall along with an oscilloscope for both transmit and receive audio. This makes it easy to monitor AF characteristics such as microphone compressor level, filter width, notch filter, and in CW, you can monitor received CW keying wave forms.
The combination of the touch screen and the multi-dial knob offers quick and smooth operation. When you push the multi-dial knob, menu items are shown on the right side of the display. You can select an item by touching the screen and can adjust the levels by turning the multi-dial knob.
The optional RC-28 remote encoder enables you to add an external Sub dial for controlling the Sub band. Main band and Sub band can be switched with the F1 and F2 buttons and can be controlled with the RC-28. The LED above the F1 and F2 buttons turns ON to show the active band.
The IC-7610 has a DVI-D connector for an external display. Operating frequency, setting information and spectrum scope can be observed on a large external display.
When used with an SD card or USB flash drive, various contents including firmware updates, memory channels, captured screen images, and other personal settings, can be saved and loaded. TX/RX audio, voice memories, RTTY/CW memories and RTTY decode logs can be saved and used on the SD card.
The IC-7610 can output I/Q signals to a connected PC. Using the I/Q signals on the HDSDR (freeware), you can listen to received signals, or observe the spectrum scope on the PC. Used in combination with the CW Skimmer (Shareware) or N1MM Logger+ (Freeware), you can virtually decode all Morse signals in the operating band. This function is very useful for contesting and DX hunting, such as monitoring the activity in the band, and effective callback in split operation.
Whether from a remote part of your home QTH, or on a remote location somewhere around the world, the RS-BA1 software enables you to operate your IC-7610. Not only can you control the radio settings and have both RX/TX audio paths, you are able to display a single band spectrum scope with the waterfall. With the addition of an Ethernet connector, a base station computer is not required.
・ BNC type RX IN/OUT connectors for a receiver antenna or external BPF/preamp connection
