User manual ICOM IC-280

[. . . ] IP2 (2nd order Intercept Point) * Measurements were made using custom equipment, due to the limits of normal signal generators (SG) and duplexers to +85 dBm. The IP2 figure is a typical value. +112. 4dBm OUTPUT [dB] 250 200 START 0Hz *RBW 10Hz VBW10Hz SWP 40s STOP 2. 000 kHz ATT 10dB 150 S9 +60dB equivalent signal input 100 Band pass filter 50 OUTPUT ­140 ­120 ­100 (0. 224µV) ­80 ­60 ­40 ­20 0 (224mV) 20 40 60 80 100 120 INPUT [dBm] Double conversion superheterodyne system While multiple IF stages can become a source of distortion products and spurious responses, the IC-280 utilizes Icom's 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 superheterodyne receivers. 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 distortion, the IC-280 design utilizes high-grade mechanical relays along with large capacitors and toroidal coils; resistant to magnetic saturation, providing superior linearity, and greatly reducing distortion. 3 DIGI-SEL (Digital pre-selector) The DIGI-SEL (digital pre-selector) is a very narrow, user adjustable, pass band filter designed to automatically track the operating frequency, attenuating interference from out-of-band signals. [. . . ] The AGC voltages detected in front of and behind the digital IF filter in the DSP unit. The first AGC loop prevents the saturation of the 1st IF amplifier from strong signals outside the pass-band filter, and improves the dynamic range in the presence of strong 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. 2nd mixer Image rejection mixer IF AMP IF AMP IF AMP The well-selected components provide premium performance Mechanical relays Mechanical relays using gold contacts have excellent deterioration resistance and superior conductivity. DSP Circuit Hi-spec 1st IF filter 90° Phase shifter IF AMP A/D AMP BPF AMP AGC DET 90° Phase shifter AGC Loop line AGC DET The IC-280 uses custom made Hi-spec 1st IF filters (roofing filters), selected especially for excellent IMD characteristics. D/A Large coils To reduce secondary distortion, large coils and capacitors are used in the high-amplitude filter switching circuits. The use of non-linear semiconductors is minimized. The IC-280 accommodates both the "on-the-fly" operator as well as the most avid "tweaker" operator by providing tunable AGC preset and manual AGC level controls. The AGC time constants can be set in the 3 presets (slow, medium and fast), adjustable from 0. 1­6 sec. Then the addition of the AGC VR control enables the user to "tweak" or fine tune the AGC reaction time. DSP The transmitter and receiver use a 32-bit floating point DSP, offering the high performance of 1800 MFLOPS processing. Also, the spectrum scope DSP achieves 1200 MFLOPS of peak performance. High stability OCXO unit Frequency control of the IC-280 is maintained by the high stability Oven Controlled Crystal Oscillator. The OCXO achieves frequency stability of ±0. 05ppm across the specified temperature range, meaning that the frequency will deviate only 5Hz out of every 100 MHz!This specification is equivalent to that of specialized measuring equipment such as signal generators or spectrum analyzers. Also, a 10MHz reference signal can be input to the OCXO unit IC-280 or output for use by external equipment. 5 Power amplifiers The power 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. Tx/Rx DSP: TMS320C6727 Internal Clock: 250MHz 32-bit floating point Floating point calculation: 1800MFLOPS Operation It means nothing to have multiple functions or high specifications if you cannot effectively use the functions. You can monitor band conditions between the selected sweep edges (Fixed mode), as well as sweep a selected band width centered on the receiving frequency (Center mode). Digital IF filter The DSP-based digital IF filter of the IC-280 rejects signals out of the pass band, and keeps the desired signal free of any distortion or degradation of quality. Depending on the operating 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 filter width, even while receiving a signal. In addition, the scope has useful functions including scope attenuator (10dB/20dB/30dB), 2 types of marker (Transmit, Receiver) and Max hold function. By using the excellent performance of the 32-bit floating point DSP, this separation is made immediately without a delay and extracts signals from noise components. The noise reduction suppression level is variable in 16 steps to adjust the balance between the S/N ratio and clarity. S/P DIF optical interface (Input/Output) SSB data mode When you narrow the IF filter passband to 500Hz or less in SSB mode or SSB-data mode operation, the IC-280 automatically selects special band pass filters (BPF). The BPF has a very sharp edge like a CW filter for better rejection of interfering signals. Along with the BPF setting, the IC-280 has a 1/4-tuning step function for easier tuning operation. Digital voice recorder The digital voice recorder (DVR) is a convenient function for contests, DX-peditions, portable operation and even regular operation. Record your callsign, CQ, or other station information into a memory. Easy-to-access independent "Record (REC)" and "Play" buttons are on the front panel. Firmware upgrade for maintaining the best performance Digital voice memory (Record and Play buttons) RX audio HPF/LPF setting The IC-280 has a separate RX HPF/LPF setting for each mode. The high-pass filter and low-pass filter are adjustable for each mode. Icom will always provide the latest firmware for keeping the radio up to date. Just download the latest firmware from the Icom web site whenever a new version has been uploaded, and update your IC-280 via the USB memory. Please check; http://www. icom. co. jp/world/support/download/firm/index. html RX audio HPF/LPF setting 8 Transmit The IC-280 has a tough, reliable transmitter generating stable output power even during high duty cycle operation. [. . . ] *2 Some frequency ranges are not guaranteed. USB mode only. TRANSMITTER · Output power (continuously adjustable) : SSB, CW, RTTY, PSK31, FM 5­200W AM 5­50W · Modulation system : SSB DPSN modulation AM Digital low power modulation FM Digital phase modulation · Spurious emission : Harmonics More than 60dB (HF bands) More than 70dB (50MHz band) Unwanted emissions More than 50dB (HF bands) (Except harmonics) More than 66dB (50MHz band) · Carrier suppression : More than 63dB · Unwanted sideband suppression: More than 80dB · TX variable range : ±9. 999kHz · Microphone impedance : 600 (8-pin connector) FM (BW: 15kHz at 12dB SINAD) 28­29. 990MHz 0. 5µV (Pre-amp 1 ON) 50. 0­54. 0MHz 0. 32µV (Pre-amp 2 ON) · Squelch sensitivity (Pre-amp: OFF): SSB, CW, RTTY, PSK31 Less than 5. 6µV FM Less than 1µV · Selectivity (representative value): SSB, RTTY More than 2. 4kHz/­3dB (BW: 2. 4kHz) Less than 3. 6kHz/­60dB CW (BW: 500Hz) More than 500Hz/­3dB Less than 700Hz/­60dB AM (BW: 6kHz) More than 6. 0kHz/­3dB Less than 15. 0kHz/­60dB FM (BW: 15kHz) More than 12. 0kHz/­6dB Less than 20. 0kHz/­60dB · Spurious and image : More than 70dB rejection ratio · Audio output power : More than 2. 6W at 10% distortion with an 8 load · Mode : USB, LSB, CW, RTTY, PSK31, AM, FM · Number of channels : 101 (99 regular, 2 scan edges) · Antenna impedance : 50 unbalanced (Tuner off) · Antenna connector : SO-239×4 and BNC×1 · Power supply requirement: 85­265V AC · Temperature range : 0°C to +50°C; +32°F to +122°F · Frequency stability : Less than ±0. 05ppm (0°C to +50°C, after warm up) RECEIVER : Double conversion super-heterodyne system · Intermediate frequencies : 1st 64. 455MHz 2nd 36kHz · Sensitivity (typical) : SSB, CW, RTTY (BW: 2. 4kHz at 10dB S/N) 0. 1­1. 799MHz 0. 5µV (Pre-amp 1 ON) 1. 8­29. 999MHz 0. 16µV (Pre-amp 1 ON) 50. 0­54. 0MHz 0. 13µV (Pre-amp 2 ON) AM (BW: 6kHz at 10dB S/N) 0. 1­1. 799MHz 6. 3µV (Pre-amp 1 ON) 1. 8­29. 999MHz 2µV (Pre-amp 1 ON) 50. 0­54. 0MHz 1µV (Pre-amp 2 ON) · Receive system · RIT variable range : ±9. 999kHz · PHONES connector : 3-conductor 6. 35 (d) mm (1/4) · EXT SP connector : 2-conductor 3. 5 (d) mm (1/8) /8 · Frequency resolution : 1Hz (minimum) · Power consumption : Tx Max. power 800VA Rx Stand-by 200VA (typ. ) Max. audio 210VA (typ. ) · Dimensions (W×H×D): 425×149×437 mm; (projections not included) 1623/32×57/8×177/32 in · Weight (approx. ) : 22. 5kg; 49. 6lb All stated specifications are subject to change without notice or obligation. 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