* Icom calls the roofing filters “Hi-spec 1st IF filters”, because their You can select the filter widths from 15kHz, 6kHz and 3kHz, depending on operating mode. Before the 1st amplifi er, the IC-7800's three Hi-Spec 1st IF filters* (roofing filter) adjacent signals. The mechanical relay reduces secondary distortion at the primary stage of signal processing.Ĭontesters know how frustrating it is to experience a strong adjacent signal that's blocking the receiver from pulling out a weaker signal.
The IC-7800 uses durable mechanical relays for BPF switching instead of non-linear semi-conductors, like switching diodes which can cause distortion. This allowed us to explore new technical dimensions. A first in Ham radio! To achieve this superior receiver performance, Icom’s engineering team completely re-engineered the whole analog circuit and matched it to the DSP units.
Icom’s considerable 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. Simply put, Icom has developed the ultimate Amateur HF transceiver. The result is TWO identical receivers with 110dB dynamic range, +40dBm 3rd order intercept point, and unmatched DSP technology in the HF bands something that has never been achieved in Ham radio! The IC-7800 is an artistic fusion of over 40 years analog RF circuit development expertise and cutting-edge digital technology. The IC-7800 will be viewed as the pinnacle radio for years to come.
It takes amateur radio to a whole new level of performance. Some of today’s operators still feel the IC-781 is the pinnacle in amateur radio design. The IC-781 set benchmarks back in the 1980’s as that generation’s ultimate HF transceiver. The IC-7800’s somewhat familiar looks will remind many HF operators of the IC-781. Continuing with this tradition, Icom announces the ground-breaking IC-7800! Starting with the first analog PLL circuit in the IC-200 to the ground-breaking 32-bit DSP technology used in the IC-756PRO, Icom’s developed some of the most innovative radio equipment ever made. Icom is a pioneer in the amateur radio world.
IC 7800 SERIES
Note that 7900 series provides fixed regulated voltages from – 5V to – 24 V.Ĭircuit Diagram of Fixed Negative Voltage Regulator This series (7900) is the negative-voltage counterpart of the7800 series . The 7900 series of IC regulators is commonly used for this purpose. This IC regulator provides a fixed negative ouput voltage. The input capacitor (C1) is used to prevent unwanted oscillations. The output capacitor (C2) acts basically as a line filter to improve transient response. Capacitors, although not always necessary, are sometimes used on the input and output. The unregulated input voltage Vi is connected to the IC’s IN terminal and the IC’s OUT terminal provides + 12V. You can see how the 7812 IC is connected to provide a fixed d.c. The figure above shows the circuit diagram of fixed positive voltage regulator. Circuit Diagram of Fixed Positive Voltage Regulator
0 kommentar(er)
