THE ULTIMATE PRODUCT OF 40 YEARS ACCUMULATED RF EXPERTISE
Icom has been developing radio communication equipment for over
fortyyears. Our history has been technical challenge and excellence from
thefirst 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,
withcutting 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!
1. Astonishing + 40dBm 3rd order intercept point in HF bands
2. Two completely independent receiver circuits allowing reception of two different bands in different modes simultaneously
3. Four 32-bit floating point DSP units ( Two for the receivers, one for the transmitter, one for the spectrum scope)
4. Full power, full duty cycle 200W output
5. 0.05ppm high stability OCXO unit installed as standard
+ 40dBm IP3 ( 3rd order Intercept Point)
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.
Mechanical relay BPF ( Band Pass filter) 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.
Automatic tracking pre-selector
The pre-selector works from 1.5MHz to 30MHz. The preselector
automatically tracks the intended signal, keeping the pre-selectorý fs
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.
Double conversion super-heterodyne system
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.
AGC loop management using 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.
AGC Volume knob for fine tuning
AGC setting screen In addition to the preset AGC time constants ( slow,
medium and fast) , the manual AGC volume provides flexible detailed AGC
tuning.
Two completely independent receiver circuits
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!
Digital IF filter
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.
Manual notch filter with adjustable notch filter characteristics
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.
Four 32-bit floating point DSP units and 24-bit AD/ DA converters
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 Icomý fs analog RF
technology and experience.
200W output power at full duty cycle
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.
Ultra high stability OCXO unit
Your IC-7800 will be the reference point on the band with a standard
stability of & plusml; 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.
RTTY/ PSK31 operation without PC connection
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.
Info dan harga terbaik hubungi :
Raja Survey Grup
JL Pesantren no.64 Jurang Mangu Timur
Pondok Aren
Tangerang Selatan 15222
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