IC-7700_broch.pdf

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1、HF/50MHz TRANSCEIVER Perfection In its purest form. 1 To Amateurs That Share An Appreciation of Design and Value 2 HF/50MHz TRANSCEIVER The IC-7700 For Operators With A Common Vision of Design and Value. The essential elements for top-of-the-line HF transceiver performance begin with an exceptionall

2、y linear, low distortion design. Starting with electronic component selection, Icom integrates state-of-the-art analog performance with the latest digital technology to achieve superior receiver performance. As a result, the IC-7700 achieves More than 110dB dynamic range More than +40dBm IP3 More th

3、an +110dBm IP2 in the HF bands. Those who choose the IC-7700 will know they have the best receiver performance available. The IC-7700 will change forever what you expect as the normal sound of the HF bands. 110dB dynamic range and +40dBm 3rd order Intercept Point (IP3) The IP3 performance of a radio

4、 can be improved by sacrifi cing sensitivity, but Icom considers this a poor choice. To achieve REAL high-performance, Icom reviewed all of the analog re- ceiver circuitry. The IC-7700 employs mechanical relay BPF switching, a digitally tuned pre-selector, and three Hi-spec 1st IF filters (roofing f

5、ilter) in a clean and simple double-con- version superheterodyne de- sign. By balancing the analog and DSP functions, the IC- 7700 provides superior sensi- tivity simultaneously with a superb dynamic range of 110 dB, and +40 dBm IP3 (even in USB mode with 2.4 kHz filter bandwidth). Better than +110d

6、Bm 2nd order intercept point (IP2) An IP2 point of more than +110 dBm* means the 2nd order dis- tortion from strong broadcast stations will be completely elimi- nated. The endless pursuit of leading analog circuit engineering makes it possible to achieve this leading edge level of perfor- mance. * M

7、easurements were made using custom equipment, due to the limits of normal signal generators (SG) and duplexers to +85 dBm. The IP2 fi gure is a typical value. Double conversion superheterodyne system While multiple IF stages can become a source of distortion products and spurious responses, the IC-7

8、700 utilizes Icoms original image-rejection mixers in a simple double conversion superheterodyne. This reduces distortion and produces a much cleaner audio signal compared to triple or quadruple super- heterodyne receivers. High specifi cation inband IMD In-band IMD (Intermodulation Distortion)creat

9、es undesired spuri- ous signals as a consequence of non-linear processing of mul- tiple signals. All (2nd, 3rd or even higher)orders of IMD performance are superior in the IC-7700. The improvement will be especially evident in CW mode. Youll notice the difference as you copy weak signals without int

10、ernal distortion or noise. Inband IMD characteristics Band pass fi lter While some may lead you to believe that coils and capacitors are all created equal, at Icom we know design excellence. Rather than using switching diodes that can introduce distor- tion, the IC-7700 design utilizes high-grade me

11、chanical relays along with large capacitors and toroidal coils; resistant to mag- netic saturation, providing supe- rior linearity, and greatly reducing distortion. 3 Dynamic range characteristics (in 14MHz band) Audio output level Input level at the antenna connector dBm IP3 (3rd order Intercept Po

12、int) 3dB dB 50 40 30 20 10 0 Sensitivity 3rd order Intermodulation Noise floor level Dynamic range 110dB +40dBm INPUT dBm OUTPUT dB OUTPUT 14012010080604020120100806040200 100 150 200 250 50 IP2 (2nd order Intercept Point) +112.4dBm (224mV)(0.224V) Receiver Performance REF 20.0dBm *A_Write NormB_Bla

13、nk Norm10 dB/ REF 20.0dBm *A_View NormB_Blank Norm10 dB/ START 0HzSTOP 2.000 kHz *RBW 10HzVBW10HzSWP 40sATT 10dB REF 20.0dBm *A_Write NormB_Blank Norm10 dB/ START 0HzSTOP 2.000 kHz *RBW 10HzVBW10HzSWP 40sATT 10dB START 0HzSTOP 2.000 kHz *RBW 10HzVBW10HzSWP 40sATT 10dB S9 equivalent signal input S9 +

14、60dB equivalent signal input S1 equivalent signal input 110dB Dynamic Range and +40dBm IP3 Serious ham operators always try to advance their communication and technical skill and to improve their stations capability to the limit. The IC-7700s astonishing +40dBm IP3 capability will give you further b

15、ackup in these efforts. Contesting and DXing will be the absolute best with the IC-7700! DIGI-SEL (Digital pre-selector) The DIGI-SEL (digital pre-selector) is a very narrow, user ad- justable, pass band fi lter designed to automatically track the op- erating frequency, attenuating interference from

16、 out-of-band signals. While the pre-selectors pass-band remains centered on the operating frequency, on the fl y adjustments are possible via front panel controls. The DIGI-SEL is especially useful for multi-transmitter operation and near strong broadcast stations by reducing the 2nd, 3rd, and even

17、higher order IMD compo- nents from other stations. Pre-amplifi ers The IC-7700 has a total of 4 pre-amplifiers, two for the HF bands and two for the 50MHz band. The purpose of pre-ampli- fi ers is to improve receiver sensitivity for the pursuit of higher gain and a better noise fi gure. The IC-7700

18、employs a noiseless feedback design with push- pull amplifi ers. Using feedback transformers, the pre-amplifi ers provide a high IP3 while keeping a low noise fi gure. 1st mixer The 1st mixer stage is driven with a signal from the high-drive Local Oscillator with excellent C/N. A 16V p-p of high-lev

19、el LO signal is applied to the mixer to improve intermodulation char- acteristics while avoiding a parasitic oscillation or noise. Three Hi-Spec 1st IF fi lters (Roofi ng Filter)*1 The IC-7700 employs three Hi-Spec 1st IF fi lters (roofi ng fi lters) of 15kHz, 6kHz and 3kHz before the 1st IF amplifi

20、 er. Icom or- dered special customized high specifi cation devices to improve IMD and achieve better impedance characteristics. As a result, the 3kHz 1st IF fi lter provides approximately 134dB*2of block- ing dynamic range and allows you to pull out a weak signal in the presence of strong adjacent s

21、ignals. *1 Icom calls the roofi ng fi lters “Hi-spec 1st IF fi lters”, because their per- formance is much better than regular IF fi lters. *2At 14.1MHz receive, with 5kHz separation of interference signal. 2nd-stage image rejection mixer The 2nd-stage image rejection mixer processes signals to reje

22、ct spurious image responses. In conjunction with the Hi-spec 1st IF fi lters (roofi ng fi lters), image rejection of greater than 100dB is realized. The analog image rejection mixers linearity makes it possible to use a simplifi ed receiver design. This improves the distortion performance of the rec

23、eiver. 50MHz band preamplifi er and mixer The IC-7700 was designed with the 6m aficionado in mind. Rather than sharing circuits used for HF, a separate preamplifi er and mixer was designed especially for 6m. This greatly improves the receiver sensitivity by reducing intermodulation characteris- tics

24、, enabling weak signal works without distortion or interference from strong signals in the band. Two 32-bit fl oating point units Two independent DSP units are built-in: One for the transmitter and receiver; and one for the spectrum scope. The IC-7700 ex- 4 3kHz fi lter characteristics (500kHz span)

25、 Hi-Spec 1st IF fi lters (Roofi ng fi lter) 3kHz fi lter characteristics (50kHz span) REF0.0dBm30.0dBmMKR 14.16MHzDL 10dB/ 0dB 8.73dmB *A_Write Norm B_Blank Norm START0HzSTOP 30.00MHz RBW300kHzVBW300kHzSWP200msATT10dB DIGI-SEL Characteristics in 14MHz band MARKER 14.16MHz DIGI-SEL unit Two AGC Loops

26、 The IC-7700 has two AGC loops. The AGC voltages detected in front of and behind the digital IF fi lter in the DSP unit. The fi rst AGC loop prevents the saturation of the 1st IF amplifi er from strong signals outside the pass-band filter, and improves the dynamic range in the presence of strong adj

27、acent signals. The other AGC loop detects the AGC voltage at the digital IF fi lter output which has only passed the intended signal and draws the full potential from the digital IF fi lter. The IC-7700 accommodates both the “on-the-fl y” operator as well as the most avid “tweaker” operator by provi

28、ding tunable AGC preset and manual AGC level controls. The AGC time constants can be set in the 3 presets (slow, medium and fast), ad- justable from 0.16 sec. (0.38 sec. in AM)delay. Then the addi- tion of the AGC VR control enables the user to “tweak” or fi ne tune the AGC reaction time. High stabi

29、lity OCXO unit Frequency control of the IC-7700 is maintained by the high sta- bility Oven Controlled Crystal Oscillator. The OCXO achieves frequency stability of 0.05ppm across the specifi ed tempera- ture range, meaning that the frequency will deviate only 5Hz out of every 100 MHz! This specificat

30、ion is equivalent to that of specialized mea- suring equipment such as signal generators or spec- trum analyzers. Also, a 10MHz reference signal can be input to the IC-7700 or output for use by external equipment. Mechanical relays Mechanical relays using gold contacts have excellent deterio- ration

31、 resistance and superior conductivity. Hi-spec 1st IF fi lter The IC-7700 uses custom made Hi-spec 1st IF fi lters (roofi ng fi l- ters), selected especially for ex- cellent IMD characteristics. Large coils To reduce secondary distortion, large coils and capacitors are used in the high-amplitude fi

32、lter switching circuits. The use of non-linear semiconductors is minimized. DSP The transmitter and receiver use a 32-bit fl oating point DSP, offer- ing the high performance of 1800 MFLOPS processing. Also, the spectrum scope DSP achieves 1200 MFLOPS of peak performance. Power amplifi ers The power

33、 amplifiers use a combination of push-pull final with two MRF150 transistors, having proven reliability in ultra professional communications. These devices generate a stable 200W of output power from HF to 54MHz. 5 90 Phase shifter 90 Phase shifter AGC Loop line DSP Circuit 2nd mixer Image rejection

34、 mixer A/D D/A AGC DET AMP IF AMP IF AMP IF AMP IF AMP BPFAMP AGC DET OCXO unit Tx/Rx DSP: TMS320C6727 Internal Clock: 250MHz 32-bit fl oating point Floating point calculation: 1800MFLOPS The well-selected components provide premium performance Receiver Performance 7-inch wide color TFT LCD While Ic

35、oms RF engineering team reviewed receiver designs for how the IC-7700 hears a signal, close attention was also paid to how the operator sees a signal. Details such as re- sponse time, color, resolution, and visibility were extremely im- portant. Thus, an active matrix 7-inch (800 480 pixels) TFT col

36、or display was selected as the IC-7700s display. The dis- play provides superior performance in response time, color, resolution, visibility and more. The large display shows operat- ing frequencies, various settings and operating conditions as well as the spectrum scope, S-meter and RTTY/PSK31 de-

37、coded messages. The S-meter shows an analog-like swinging needle that is smooth and accurate. In addition to the analog like-style meter, the IC-7700 has a digital multi-function graphic meter and edgewise meter - chose your favorite style! Further more, the IC-7700 has a VGA connector for an extern

38、al monitor and an S-meter connector for an external analog S-meter. USB ports on the front panel Two USB ports on the front panel allows you to easily connect a USB type keyboard or USB memory stick to save transceiver settings, update fi rmware, or transfer settings to other IC-7700. Making big sco

39、res means keeping your team fresh on those long DX-peditions or Multi-Operators contests. Swapping out operators usually involves time-wasting radio tweaks, because each operator has their own favorite settings to best match their operating style. This all changes with the USB drives! Prior to a con

40、test, operators may record their preferred IC-7700 settings such as fi lter, Digital Voice Recorder (DVR) memories, antenna settings, etc. When its their turn to operate, simply insert their USB Drive into the IC-7700. In a fl ash, the IC-7700 is now “their rig”, and theres nearly zero down time! RT

41、TY /PSK31 operation without PC connection The IC-7700 has a built-in RTTY and PSK31 modulator/demodu- lator. By simply connecting a USB key-board, you can immedi- ately start enjoying these modes. In addition, you can pre-program transmit messages in the internal message memory or a USB memory stick

42、 and transmit them even without typing a message from a USB keyboard. Also, received messages can be stored to a USB memory stick and transferred to your PC. 4 antenna connectors The IC-7700 has 4 antenna connectors (ANT1 to ANT4) with an automatic antenna selector. Once you program the operat- ing

43、bands in each antenna memory, the IC-7700 will automati- cally select the antenna as you change the operating band. The usage type for each antenna can be set for Tx/Rx use, Rx only* use and off line. The antenna switch button allows you to change the operating antenna temporarily. * Rx setting is a

44、vailable for ANT4 only. 6 Two USB ports Operation Assess the Situation and Respond Instantly It means nothing to have multiple functions or high specifi cations if you cannot effectively use the functions. The IC-7700 centralized all the operating information on a 7-inch wide TFT display offering su

45、perior operation. Real time spectrum scope With a dedicated DSP unit, the IC-7700 spectrum scope achieves 80dB of dynamic range at the signal input level. It also improves the scope response time and signal resolution, so that it is possible to accurately tune to the intended signal as you see it on

46、 the spectrum scope screen. The spectrum scope range can be set independently from the receiving frequency. You can monitor band conditions between the selected sweep edges (Fixed mode), as well as sweep a se- lected band width centered on the receiving frequency (Center mode). In addition, the scop

47、e has useful functions including scope at- tenuator (10dB/20dB/30dB), 2 types of marker (Transmit, Receiver) and Max hold function. The mini scope function is convenient for continuous monitoring even while adjusting the set mode. Digital twin PBT The digital twin PBT eliminates interference and noi

48、se from sig- nals above and below your frequency by changing the IF fi lter bandwidth. The IF shift function allows you to shift or move the IF passband to either side to more accurately receive the sig- nal. The passband width, shift direction and steps (50Hz) are graphically displayed on the LCD.

49、You can reproduce the signal as you like to hear it. Digital IF fi lter The DSP-based digital IF filter of the IC-7700 rejects signals out of the pass band, and keeps the desired signal free of any distortion or degradation of quality. Depending on the operat- ing situation, for example handling a pile-up or receiving a very weak signal, you can flexibly change sharp and soft filter shapes or reduce or shift the fi lter width, even while receiving a signal. Manual notch fi lter and auto notch fi lter The manual notch filter controlled by the DSP has extremely sharp