INSTRUCTION MANUAL EaiIcomFOREWORD ‘Thank you very much for choosing this ICOM product ‘The most sophisticated, 144MHz all mode transceiver on the matket today, the IC-275H is the result of both advanced ICOM engineering and state-of-art computer interface technology from ICOM such {as the new CI-V System: a feature that allows for easy and convenient computer control of your IC-275H. In addition, the IC-275H is equipped with ICOM's pioneering new DDS (Direct Digital Synthesizer) System, an advanced, computer-developed innovation that eliminates the need for a PLL Circuit in the 1C-275H, and it delivers 100 full watts of high output power. ‘This recent engineering development is further evidence of ICOM’s continuing commitment to meeting ‘the increasingly sophisticated hi-tech needs of today’s Amateur Radio operators by providing a product that operators require, To fully understand and appreciate the uses of your new IC-275H, please study this instruction manual carefully prior to operation. Feel free to contact any authorized ICOM Dealer or Service Center if you have questions regarding the operation or capabilities of the 1C-275H. UNPACKING = "| Accessories Ory. @ Microphone (HM-12) ® 0C power cable. @ External Speaker Plug @key Plug @ Microphone Hanger © Spare Fuses (DC cable, 208) D Spare Fuses (PA unit, 3A)SECTION SECTION SECTION SECTION SECTION SECTION SECTION SECTION SECTION SECTION SECTION SECTION SECTION SECTION SECTION TABLE OF CONTENTS FEATURES. CONTROL FUNCTIONS coven . 1 FRONT PANEL, , 2 FREQUENCY DISPLAY 2. REAR PANEL INSTALLATION : 1 PLANNING : 2 MOUNTING THE TRANSCEIVER, 3 ANTENNA 4 GROUNDING. INTERCONNECTIONS . . . : POWER SUPPLY, CONNECTING A LINEAR AMPLIFIER CONNECTING AN AFSK TERMINAL UNIT MIC CONNECTOR INFORMATION Balt ACC(1} SOCKET INFORMATION : QS SOCKET INFORMATION. Se REMOTE CONTROL JACK (CI-V) INFORMATION. |. GENERAL OPERATION INITIAL SETTINGS, FM OPERATION : 588. OPERATION CW OPERATION PACKET AND AMTOR OPERATIONS. ct RTTY OPERATION Sy SSTV OPERATION FUNCTIONS OPERATION... . cede eete eee SPEECH COMPRESSOR OPERATION | || PREAMP SWITCH OPERATION AGC OPERATION. NOISE BLANKER (Na) OPERATION SUBAUDIBLE TONE ENCODER AND 1750H2 TONE CALL OPERATIONS DUPLEX (SPLIT FREQUENCY) OPERATION DATA SWITCH OPERATION. PASSBAND TUNING OPERATION NOTCH FILTER OPERATION 10 RIT OPERATION 11 MICROPHONE UPIOOWN OPERATION 12. SWR READING OPERATION MEMORY AND SCANNING OPERATION. VFO A AND VFO 8 SELECTION MEMORY CHANNEL AND VFO SELECTION MEMORY DATA TRANSFER PROGRAMMING MEMORY CHANNELS. PROGRAMMING THE CALL CHANNEL MEMORY CLEARING SCANNING OPERATION MAINTENANCE AND ADJUSTMENT 1 MAINTENANCE 2 ADJUSTMENTS INSIDE Views. OPTION INSTALLATIONS : CAUTIONS «0... eee re BLOCK DIAGRAM SPECIFICATIONS. ‘OPTIONS SCHEMATIC DIAGRAM . cece 3 5 10 12 “4 4 4 14 14 15 15 16 16 16 ” ” 18 19 19 19 a 23 2 26 2 27 27 2a 2a 28 29 a n 32 23 2 Pa 4 4 35 36 36 7 40 40 41 3 45 46 4“ 48 SEPARATE1. FEATURES MICOM’S NEWLY DEVELOPED STATE-OF-THE-ART FREQUENCY SYNTHESIZER ‘©Smsee lockup time. ICOM proudly announces its recent technological breakthrough in developing a new frequency synthesizer system: the ICOM DDS (Direct Digital Synthesizer) unit. Operating in just § milliseconds, this new system provides one of the fastest transceiver lockup times available on the market today, and Is ideal for use with the popular PACKET and AMTOR communications systems. ICOM engineering has achieved this through the design of a sophisticated PLL UNIT Which mixes, in split second time, DDS generated source frequencies in an advanced double phase-locked loop system. MNEWLY DEVELOPED ICOM CPU INSTALLED ‘©Built.in 99-channel large memory capacity. ‘© Advanced remote control system. eary-to-read display. ‘Scanning versatility. Ninety-nine programmable memories are provided in the IC-275H to store frequency, mode, subzudible tone frequency, subaudible tone function ON/OFF, duplex direction, and offset frequency information, These memories are backed up by 2 lithium backup battery for up to five years, Full communications using @ personal computer equipped with an RS-232C jack are possible by using the serial port mounted on the rear panel of the IC-275H. The computer controls frequency, mode, VFO AVB selection, and memories when an appropriate interface is used. The serial port uses a standard 1200 baud data rate. ‘An LCD (Liquid Crystal Display) in the IC-275H uses a soft orange illumination for easy visibility when operating on bright days. This display indicates the VFO in use, operating mode, memory channel, split mode, scan mode and other information, The 1C-275H incorporates a total of four separate scanning func: tions for easy access to a wide range of frequencies. *MEMORY SCAN repeatedly scans the entire 99-channel memory in sequence: *PROGRAMMED SCAN offers detailed coverage of a specific fre ‘quency range through repeated scanning *SELECTED MODE MEMORY SCAN automatically monitors all memories which contain programmed frequencies with a similar mode. ‘SKIP SCAN allows you to continuously scan your favorite pro: ‘grammed memory channels. M OUTSTANDING RECEIVER PERFORMANCE ‘©PBT and NOTCH control ICOM’s Passband Tuning and Notch Filter systems have been incorporated in the past as standard high class features in ICOM HF transceivers, but now these convenient features can also be enjoyed in @ VHF transceiver: the IC-275H, Passband Tuning allows con: tinuous center frequency adjustment of the IF passband, while the IF Notch Filter provides clear operating reception even in the presence of strong interference.‘¢High sensitivity, high dyna MCOMPLETE VHF TRANSCEIVER ‘Compact size and 100W output power. ‘@PACKET, AMTOR operations. ‘¢Full break-in function, MOPTIONS AVAILABLE AG-25 PREAMPLIFIER UNIT UT.36 VOICE SYNTHESIZER UNIT UT34 TONE SQUELCH UNIT CT-16 SATELLITE INTERFACE UNIT CT-15 *AQS ADAPTER FL83 CW NARROW FILTER CR.64 HIGHSTABILITY CRYSTAL UNIT The IC-275H RF amplifier uses a low noise figure, high gain, disk-type GaAs-FET (3SK121) for VFH applications. Also, high sensitivity and a very high dynamic range are ensured since it uses a balanced:type mixer with Junction-FETs (2SK125) in the mixer stage. ‘The 1C-275H's compact size - only 241mm(9.5")W) x 95mm (3.7"(H) x 239mm(9.4)(D) - simplifies installation in most mobile and portable situations: in automobiles, airplanes, boats or even in sulteases, And even though the IC-276H is conveniently compact, it delivers 100 full watts of output power. The rear pane! of the IC-275H has an easy-to-access terminal socket for AFSK (Audio Frequency Shift Keying) operation. Use the [DATA] SWITCH to rapidly switch between receive and transmit, ‘operations. This convenient function is made possible in the IC-275H by ICOM's exclusive new ODS (Direct Digital Synthesizer) System. For CW operators, both semi break-in and full bre for smooth, fast, and natural CW conversations. are provided Woatherproof 144MHz Preamplifier. Announeess the displayed frequency, Provides you with interference-free communications, Satellite communication interface unit with 1C-475A/E. ‘See the functions listed below. +250H2 at ~6dB point. £0.5ppm (-30°C ~ +60°C) *AQS refers to “Amateur Quinmatie System” which includes the five functions listed below. Digital communication is possible with the IC-275H by using the CT-15 AQS ADAPTER, (1) EMPTY CHANNEL ACCESSING: The transceiver searches an empty channel in the band, moving to the channel automaticaly, (2) CALL SIGN SQUELCH OPERATION: ‘The squelch opens only when a received station's call sign is matched with the same programmed call sign, (3) DIGITAL CODE SQUELCH OPERATION: The squelch opens only when a received five digit code is ‘matchod with the same programmed code. (a) MESSAGE TRANSFERRING OPERATION: 14 characters in a message can be transferred for visual com ‘munications. The messages are displayed by an optional message processor. (5) DIGITAL CODE STORAGE FUNCTION: Up to eight kinds of digital codes for access can be stored2. CONTROL FUNCTION 2-1 FRONT PANEL DPOWER SWITCH (o.8) (DAF GAIN CONTROL (p. 5) YSQUELCH CONTROL (p.5) PHONES JACK (p. 5} ——— HMC CONNECTOR (p. 6, 16) @FREQUENCY DISPLAY (p. 10): ATRANSMIT INDICATOR (p. 10) RECEIVE INDICATOR (9, 10) 89 METER (p, 10) — VMODE SELECTOR SWITCHES (p.5, 19) DSPEECH COMPRESSOR SWITCH (p. 5,271 PREAMP SWITCH Ip. 5,271 AGC SWITCH [p. 5, 28 SENOISE BLANKER SWITCH (p.6, 28) SDUPLEX CHECK SWITCH Ip. 6,29) MDUPLEX SWITCH (p.6, 29) §ISUBAUDIBLE TONE FREQUENCY! TONE CALL SWITCH (o.6, 28) TONE SQUELCH SWITCH (p.61— TONE SET SWITCH (9.6, 28 — == WTRANSMITIRECEIVE SWITCH (p, 6a] igh ®OO® [E]_ METER swiTeH ‘p.6, 20. =k ‘AF POWER CONTROL (p.6,21) {#RE GAIN CONTROL {9.7.20 SCH DELAY CONTROL Ip. 7) {AF TONE CONTROL (p. 7) BMIC GAIN CONTROL (7 SPEECH SWITCH (9.7.44 2-2 FREQUENCY DISPLAY SAMEMORY MODE/MEMORY CHANNEL INDICATOR (o.11), 8 VFO INDICATOR (9. 99} $$$ MATA INDICATOR [p, 11) MODE INDICATOR (p. 11): SIFREQUENCY READOUT (9.103———,_| STONE SQUELCH INDICATOR {p. 10) t SDUPLEX INDICATOR (. 11) SASPLIT INDICATOR {p. 11) SSCAN INDICATOR (p.11) GRITISHIFT FREQUENCY INDICATOR Ip. 11): S8SKIP CHANNEL INDICATOR {p. 11) —CALL CHANNEL SWITCH (p. 8,96) {FREQUENCY TRANSFER SWITCH (p, 8,35) VFO EQUALIZING SWITCH (9, 9,24) @NOTCH FILTER SWITCH {9.9,31) ANOTCH FILTER CONTROL (p.9,31) {PASSBAND TUNING CONTROL (p.9,31) WINCREMENTAL TUNING CONTROL (p,9,32) RIT SWITCH (p. 9,32) WRIT CLEAR SWITCH (p. 9,2) \SMEMORY CHANNEL SELECTOR CONTROL (p, 10,34) “SMEMORY READ SWITCH (p, 9,35) “MEMORY WAITE SWITCH (p.9, 35) ASMEMORY CLEAR SWITCH (p. 10,36) AASCAN START/STOP SWITCH (p. 7,37) SELECTED MODE MEMORY SCAN SWITCH (p. 7,38) SATUNING STEP SELECTOR SWITCH (p. 8) ‘Mite TUNING STEP SWITCH (p. 8) VFO SWITCH (0. 8,341 8 SPLIT SWITCH (p.8,30) SIDIAL LOCK SWITCH Ip. 8) A TUNING CONTROL (p. 8) SKIP SCAN SWITCH (p, 7,29) SIDATA SWITCH (p.8,1) 2-3 REAR PANEL ANTENNA CONNECTOR (p.12, 14) 8c POWER SOCKET (p. 12,15) WREMOTE CONTROL JACK (p. 12, 18) AOS SOCKET Ip. 12,17) ene = feaccit) SOCKET Ip. 12,17) a) GH] scrtouno rensaivat ip. 12,14 EXTERNAL SPEAKER JACK (p. 121 "SPEECH COMPRESSOR LEVEL CONTROL (p. 12,27) BMIC TONE CONTROL (p. 12) DTXMETER SWITCH (p. 13,33) CW SIDETONE LEVEL CONTROL {p. 13,24) DOW BREAK-IN SWITCH (p. 13, 25) KEY JACK (p. 13, 24)2-1 FRONT PANEL @POWER SWITCH [POWER] @SQUELCH CONTROL [SQL] Soe @MODE SELECTOR SWITCHES (FMI [Use] [LSB] (CW/N} [comp] @AUTOMATIC GAIN CONTROL SWITCH [AGC] ‘This is a push-lock switch which controls the input power to the Ic-275H, This control varies the audio output level. Clockwise rotation increases the level, ‘This control sets the squelch threshold level. To turn OFF the squelch function, rotate this control completely counterclockwise, To set the threshold level higher, rotate the control clockwise. This jack accepts a standard 1/4 inch plug from headphones with an impedance of 4 ~ 1602. Stereo headphones may be used without modification. Connect a suitable microphone to this connector. The supplied hand microphone or the optional microphones listed in SECTION 14 OPTIONS are ideal ‘These switches select any of the four operating modes for the IC-275H: FM, USB, LSB, or GW, Press the appropriate switch for the desired mode. This switch turns the builtin speech compressor circuit ON and oFF. This switch turns the receiver preamplifier ON and OFF when the optional AG-25 PREAMPLIFIER is installed, The [PREAMP] SWITCH does not function when the [DATA) SWITCH described in item @ is turned ON. ‘This switch changes the time constant of the AGC circuit, When the switch is OUT, a SLOW time constant is selected. When the switch is IN, a FAST time constant is selected,(NOISE BLANKER SWITCH [NBI (3 SUBAUDIBLE TONE FREQUENCY/ TONE CALL SWITCH [TONE] Push this switch IN to reduce pulse-type noise such as that generated by automobile ignition systems. Push this switch to tun ON and OFF the Tone Squelch function alternately when the optional UT-34 TONE SQUELCH UNIT is installed, ‘This switch is used with the [TONE] SWITCH described below in item (@ for setting the subaudible tone frequency of the tone encoder function. 1C-275H (U.S.A., Australia versions) Push to activate the built-in subaudible tone circuit. 1C-275H (Europe, Sweden versions) Push to activate and transmit the 1750H? tone call Push this switch to select simplex or duplex mode operation, This switch allows the operator to monitor the transmit frequency when duplex mode is selected. This switch is used to manually switch the transceiver from transmit +0 receive mode and vice versa IN position: Transmit OUT position : Receive ‘This switch selects the meter function and indicates the following: G® RF POWER CONTROL [RF PWR] ‘swirce er RECEIVING ‘TRANSMITTING 'S-RF (OUT) | Signal strength *Reletive RF output poner ; FM: Frequency center CALCUIN) | SSB ew: Sionat strength. | ALC Tove "The [TXMETER] SWITCH on the rear panel should bein the [RFT position for indicating “lative RF output power This control varies the RF output power from 10W to maximum continuously. Rotate clockwise to inerease output power,(RF GAIN CONTROL [RF GAIN} @® CW DELAY CONTROL DELAY @3 SELECTED MODE MEMORY SCAN SWITCH [MODE-S] In SSB, CW modes: This control varies the gain of the RF stage when the transceiver isin receive mode, Rotate clockwise for maximum gain. In SSB and CW modes, the transceiver may receive signals that are stronger than the levels shown on the meter. In FM mode: ‘The control makes the variable attenuator function continuously from 0 to 2048 when the transceiver is in receive mode. This control changes the transmit to receive switching time during CW SEMI BREAK-IN operation. Adjustment depends on the keying speed used, Clockwise rotation increases the delay time. ‘This control varies the receive audio tone. Adjust the control to receive the clearest, most pleasing audio tone. ‘Adjust this control for a suitable modulation level while speaking into the microphone using your normal voice level. Rotate the control clockwise to increase the gain. This switch activates the optional UT-36 VOICE SYNTHESIZER UNIT which announces the displayed frequency in English This switch starts and stops all the IC-275H scan functions ‘This switch turns ON and OFF the SELECTED MODE MEMORY SCAN function, This switch is used for sotting the skip channel to be skipped in MEMORY SCAN.@ DATA SWITCH [DATA] (ts) “4, eer < [cal fer aa @® FREQUENCY TRANSFER SWITCH Im» vFo} Ate | Neg Push this switch to use operating modes such as PACKET or AMTOR, communications which require rapid receive and transmit switching times. Rotate this control clockwise to increase counterclockwise to decrease them. quency numbers and '*Quick, continuous rotation of the TUNING CONTROL changes ‘the frequency up or down by 10kHz, Slow rotation changes it by 2.5kH2, Push this switch to increase the tuning step by TkHz while operating in any mode. Push and rolease the switch again to return to the previous tuning step. — [position UserLseiew our 10He iN The ‘This switeh sets the tuning step rate for IMHz steps in any mode. This switeh selects VFO A or VFO 8 for tuning purposes. Each push of this switeh selects one of the two VFOs alternately. ‘This switch also selects VFO A or VFO B mode from the MEMORY CHANNEL or CALL CHANNEL mode, This switch selects the relationship of the two VFO frequencies. In the IN position, one VFO js for receive while the other VFO is for transmit, Each alternate push of this switch chooses the simplex and duplex modes. ‘This switch electronically locks the display frequency and deactivates the TUNING CONTROL. Push the switch IN and a beep sound is emitted, indicating that the function has been activated ‘This switch selects the CALL CHANNEL which is most frequently used as a call frequency. This switch operates differently depending on which mode the transceiver is in,@® VFO EQUALIZING SWITCH [A=B] @ INCREMENTAL TUNING CONTROL [-RIT# ‘This switch instantly matches the frequency and mode of operation Of the two VFOs. + The display does not change when the [A=B] SWITCH is pushed. However, confirmation of the equalizing process is possible by pushing the [VFO] SWITCH which checks the frequency and mode of the opposite VFO. This switch turns the NOTCH FILTER circuit ON and OFF. ‘This control shifts the NOTCH FILTER frequency. Adjust the ceontrol to reduce or eliminate interforing signals This control allows continuous tuning of passband selectivity by moving the filter center frequency to either side of the receive fre: ‘quency in the $$8 or CW mode. ‘This switch turns the RIT circuit ON and OFF. The “RIT” IN. DICATOR sppears on the FREQUENCY DISPLAY when the RIT function is activated. ‘This switeh clears the memory which contains the frequency shift information and resets the small incremental tuning display to “0.0”. This control shifts the receive frequency by up to 9.9kHz to either side of the frequency indicated on the FREQUENCY DISPLAY. ‘This switch selects the MEMORY CHANNEL mode. The “MEMO” INDICATOR appears on the FREQUENCY DISPLAY, and the "VFO A" or "VFO B” INDICATORS disappear. Push this switch to store displayed information in a memory channel@MEMORY CLEAR SWITCH [M-CL] @MEMORY CHANNEL SELECTOR CONTROL [MEMO] @eTer @ TRANSMIT INDICATOR [XMIT] 2-2 FREQUENCY DISPLAY 6) FREQUENCY READOUT eae @ TONE SQUELCH INDICATOR [Wee USerwcw=m DATA WomVrOmiMENG ) 145.0000-99 99 This switch clears unwanted information in any memory channel. When pushed, information in the displayed memory channel is cleared and the memory channel reverts to blank status. ‘This control is used for selecting memory channels. Refer to SECTION 2. 2 FREQUENCY DISPLAY for more informa: tion ‘The meter functions as an S-meter or Center meter during receiving, ‘and as an RF-meter or ALC-meter during transmitting. Refer to item 1 METER SWITCH. ‘This indicator lights up when the transceiver isin the transmit mode. The indicator lights up when the transceiver isin the receive mode. This readout shows the operating frequency using a 7-digit display with 100H2 resolution. “TONE-S” appears when tho transceiver is activated using the Tone ‘Squelch function with an optional UT-34 TONE SQUELCH UNIT. “TONE” appears when the transceiver is activated using the subaudible tone function (IC-275H U.S.A, Australia versions) or tone call function (IC-275H Europe, Sweden versions). —10-6) DUPLEX INDICATOR TaHSSFEW-e —oatK_ wourromuene 145.000. 0-99 99 SPLIT INDICATOR TSHSS FEW oa WPORTFORNENG 45.000.0-9999 SE (SCAN INDICATOR Tas — an TORT 145.000.0-99 99 sove-3 cure" ourer su” ry a ee ® RIT/SHIFT FREQUENCY INDICATOR Tas SaTCeR pak vrORIFORNENS eee eee 93 @SKIP CHANNEL INDICATOR THESE FHEWH ORR VrORVTOTSREND 195.000.0-99 99 ‘one-8i_oUres" SUPE Su” scan “nit (@ MEMORY MODE/MEMORY CHANNEL INDICATOR TSSUSBFILGIER — Oma WroRVFORRINT 145.006.0-99/95 tone ube DUPE SPU saw “Rit ® VFO INDICATOR convaragin on Nr i4$.000.0-99 99 Tow pune Dorm sm” Scan RIF (@ DATA INDICATOR Se Sr 145.000.0-9999 tone ure" Ourer SAIN” scan iF @DMODE INDICATOR 45000. Either “DUP+"" or “DUP—" appears when duplex mode is selected using the [DUP] SWITCH. “SPLIT” appears when separate VFOs are used for the transmit and receive frequencies SCAN" appears whenever a scan function is selected, RIT" and shift frequency appear when the RIT circuit is activated. “SKIP” appears when the displayed memory channel is programmed for skip scan. MEMO” and selected memory channel numbers (1 ~ 99, P1, P2 and ““C") appear when the MEMORY CHANNEL mode or CALL CHANNEL mode is selected “VFO A” or “VFO B" appears, indicating which VFO is currently selected when operating in VFO mode. DATA’ appears when the [DATA] SWITCH is pushed, ‘This area of the display shows the operating mode currently selected, ‘The modes available are LSB, USB, FM, CW or CW-Narrow. We2-3 REAR PANEL @Dc POWER SOCKET [DC 138V] @ANTENt ate eS] 1 GROUND TERMINAL [GND] ®accm) @® EXTER NAL SPEAKER JACK [EXT SP] aE @ SPEECH COMPRESSOR LEVEL conTA OL [COMP LEVEL] ae Oe oaseego MIC TONE CONTROL [MIC TONE] ST) Connect the DC power cable from an external AC power supply or 2 12V-type battery. Refer to SECTION 14 for information regarding ‘optional AC power supplies available from ICOM, Connect a 502 impedance antenna to this connector. The con. rector should be matched with a PL-259 UHF plug. This is a communications port designed for use with personal computer for remote operation of transceiver functions To prevent electrical shocks, TV1, BCI, and other problems, be sure {0 ground the transceiver through the GROUND TERMINAL. This socket provides signals for AQS {Amateur Quinmatie System). “This socket provides signals such as T/R switching, receiver output, ALC input, ete. Connect an external speaker to this jack, if required. Use 2 speaker with an impedance of 4 ~ 169, When using the EXTERNAL SPEAKER JACK, the built-in speaker does not function. This control varies the compression level when the (COMP] SWITCH is pushed IN. The present circuit gain is approximately 1048, ‘The bass and treble response of your transmitted signal may be altered with this control adjustment, ae@TXMETER SWITCH [TX-METER] (DCW SIDETONE LEVEL CONTROL [cw SIDETONE] SHU ee Os (BOW BREAK.N SWITCH [8K-IN] SSN aataa e OGs KEY JACK [KEY] ese ‘el oe In the transmit mode, this switch selects one of three meter func: tions ORF oseT swe he meter indicates the relative RF output power activated by the METER SWITCH on the front panel when itis set in the [SRF] (QUT! position. Place the switch in the [SET] position to calibrate the front panel meter for measuring the SWR of the antenna system. Refer to SECTION 6-12 for measuring pro: cedures. The front panel meter directly reads the antenna system SWR after calibration using the [SET] position. Refer to SECTION 6 - 12 for measuring procedures. ‘This control changes the audio level of the CW sidetone circuit {Adjust the control for the desired monitor volume. Place this switch in the [FULL] position for full break-in CW operation and in the [SEMI] position for semi break-in operation, Place this switch in the [OFF] position for non CW break-in opera tion, For CW operation, connect @ CW key here using the supplied key plug. 13-3. INSTALLATION 3-1 PLANNING 3-2 MOUNTING THE TRANSCEIVER 3-3 ANTENNA ‘©PL-259 CONNECTOR INSTALLATION w= = 1 Fo 6mm ae ME] I: 3-4 GROUNDING Select a location for your transceiver which allows free access to the front panel controls, good air circulation and rear clearance for access to the rear panel connections. Mobile or marine installations: ‘An optional IC-MB5 MOBILE MOUNTING BRACKET is available for mobile installation of your IC-275H. Solect @ location which ‘can support the weight of the unit, and which does not interfere with the normal operation of the vehicle or boat, When mounting the transceiver aboard a boat, place the bracket in a location where the transceiver will be less subject to vibration and ‘wave shocks, ‘Antennas play 2 very important role in radio communications. If the antenna is inferior, your transceiver cannot deliver optimum performance. A wellmatched 502 antenna and feedline will pro: Vide the desired effect. The transmission line should be a coaxial cable, The antenna system should show a VSWR of less than 1:1.5 when using a 50°2 coaxial transmission line. | Ground plane antenna |] [+Yagi beam antenna | 1) Slide the coupling ring over the coaxial cable 2) Strip the cable as in the figure, and tin about 13mm of the shield conductor. Remove the outer plastic casing and strip the center conductor insulation as in the figure. Tin the center conductor. 3} Slide the connector body onto the cable and solder. 4) Screw the coupling ring onto the connector body. | Refer to SECTION 11 CAUTIONS for detailed grounding informa: -14—4. INTERCONNECTION 4-1 POWER SUPPLY To power the IC-275H from another external power supply or any other DC power source, be sure the output voltage is 12~ 15V and ccurtent capacity is at least 20, ‘Operation with a DC power source BC power sable Use the supplied tea7se TV bertery 12V battery For safety purposes, zomamber to install FUSES in the [DC cable if connecting the IC-27SH toa vehicle bottery, Locate the fuses ae close tothe ca battery as possible, ‘*Operation with the PS-55 AC POWER SUPPLY To OC POWER SOCKET AC outlet (receptaci &) ‘The POWER SWITCH synchronizes the PS55 AC POWER SUPPLY with the 10-2754 Operation with non-ICOM AC power supplies | ToDCPOWER gf SOCKET [Use the supplien -|-y BC power cable ‘AG POWER SUPPLY 13.8V 2084-2 CONNECTING A LINEAR ‘The IC-275H is designed to operate into a load with a 502 AMPLIFIER impedance. Any amplifier used should have a 5022 input impedance for best efficiency. 1) Pin 3 (SEND) is grounded when the transceiver is in transmit Lee mode and opens when the tenssiver returns to receve mode Ne “The output condition of pin 3 contol either the transmit or “g $ Ny recive function ofthe wansciver Specification for the keying rate is 20V DC maximum, DO NOT exceed this limit 2) Pin 8 of the ACC(1) SOCKET is an ALC input for the Automatic Level Control signal from an external amplifier. ‘*Operation with an external linear ampli | feos WITH =_—a- | SETA |p Hi SEND LINEAR AMPLIFIER, a atc Ce TEP AcatN) Pin 8 | ‘ect Pin 37 J 4-3 CONNECTING AN AFSK When operating an AFSK such as RTTY, AMTOR or PACKET, TERMINAL UNIT connect the ACC(1) asin following diagram below: Using the ACC(1) SOCKET [ a -® rsx ouput Le at | terrae se coe en J saveton inoue |cusne meme connecron ea | a) ) J Ground (GND! © +8 (AFSK TERMINAL UNIT +6 | 4-4 MIC CONNECTOR INFORMATION ®AF OUTPUT @mic inpeuT— GND (Microphone ground) @+8v De OUTPUT: —@GND (PTT ground) @ FREQ UP/DOWN- rr @SQUELCH SWITCH (Front panel view)4-5 ACC(1) SOCKET INFORMATION LPS m(Coacs Bae (Rear panel view) 4-6 AQS SOCKET INFORMATION (Rear panel view) Various signals are a receiver output, modulator input, T/R changeover, etc ble from the ACC(1) SOCKET such as [FINNO, DESCRIPTION NC GND ‘SEND | The transceiver switches to transmit ‘MoD AF SQLs [ Ground mode when this terminal is grounded It is grounded when the [Xmit] switeh is placed in the IN position, Connected in the modulator stage. ‘The modulator amplification level can be changed by using the S1 SWITCH. See page 42 for the location of this switeh, ‘Output from the receive detector stage. The output level can be changed by using the $2 SWITCH on the MAIN UNIT. See page 42 for the location of this switch, [This terminal goes to ground level when the SQUELCH opens. 13.8V DC output is switched by the [POWER] SWITCH on the front panel Maximum current capacity is 1A. The function of the AQS System is described in SECTION 1 Input for external ALC voltage FEATURES, PINNO, | PIN NAME "DESCRIPTION 1 TX_E | Modulator ground. | 2 | TX MOD_| Modulator input. 3 MUTE | MUTE line for audio output and microphone input. The terminal is “LOW” while muting cac RX AF PIT SEND | This is an input terminal that the SEARCH ‘Valid signal output for CAC (Channel | Access) function, The terminal is | "HIGH" when the CAC funetion is | tivated, jutput from the receive detector stage. | Connected to the PTT circuit. The terminal is "LOW" when transmitting, transceiver. switches to in transmit ‘mode when the terminal is "LOW". HH | When searching the empty channel, the terminal is “LOW Demodulator ground. This is the CPU 1/0 terminal for set- ting the frequency and mode. When receiving a signal, this terminal is erouh | This terminal outputs 13.8V DC to an optional AQS adapter.4-7 REMOTE CONTROL JACK (CLV) INFORMATION ‘interface between the IC-275H and RS-232C port ICOM has introduced a new remote control Local Area Network, the ICOM Communication Interface-V (CLV) System using the CSMA, (Carrier Sense Multiple Access with Collision Detection) standard, A serial data bus cartes all control data. Operation is possible by installing a voltage level converter with a personal computer that has an RS-232€ serial port bc PoweR avy 20m aaFev 0047HF[O Jo O} pr fo °} Rs-232¢ uo 115 0] To comPureR ° xD fe 3 | PD =f 8 | Bw He o| S3 SWITCHES (Switches 1 ~ 10) ‘The $3 SWITCHES shown abou are located on the Locie unit, Transmitters and receivers using the ICOM CI-V System exchange terial information in the PACKET format, The contents of a data PACKET can be changed by using the S3 switches (Switches 1 to 10) on the LOGIC UNIT. ‘Switches 1 ~7 (For setting an address with your transceiver): The ON position of one of the seven switches sets an independent address for your IC-275H Switeh 8 (For setting a transceive flag): The ON position sets a flag used for sending or receiving code data fof transceive operations automatically when the frequency is changed or code data are received. ‘Switches 9 and 10 (For setting CI-V baud rate): Baud rate ‘Switch 10 2600 OFF 4800 OFF 1200 | OFF oN [300 [ow on | NOTE: The standard ICOM CI-V baud rate is 1200 baud. ~18-PCa) alg sO od a1 AMO 5-1 INITIAL SETTINGS (1) Front panel switch and control settings After all INSTALLATION instructions have been followed in SECTION 3, including connecting an antenna system, set the con: trols and switches as indicated below: 1) Check the DC output voltage if using a non-ICOM AC power supply. 2) An antenna must be connected to the ANTENNA CONNECTOR CAUTION: Transmitting without an antenna may damage the transceiver, a 3) A ground connection must be made through the GROUND TERMINAL, [[switewrcontroe [Position ~ | swiTeuiconTAor DP Power OFF (Outi | _RF GAIN Max. CW AF Max cow || @@ | DELAY Center 1 SQUELCH Max. Cow | @) | AF TONE Center| Torr ou ae | mic Gan Center PREAMP OFF (Out) Ts : OFF (Ox) | AGC Sow (Out) Tie OFF (Out) io NB OFF (Out) 7 @ Lock OFF (Out) we) xwiT ~ Receive (Out) | @ | NOTCH SWITCH OFF (Out) o SAF (Ou) | NOTCH CONTROL [Centr —_—| @| Max. COW @ | PBT “Center (2) ear panel switch settings ‘SWITCH/CONTROL _ POSITION [_SWITCH/CONTROL POSITION @) GND @| __TXMETER 5-2 FM OPERATION (1), FM receiving 1) Set the switehes and controls 2) Tum power ON. 3) Push (FM) SWITCH, “Connect ground RF BKIN OFF 1) Sot the switches and controls as explained in SECTION 5-1 ‘The [PBT] CONTROL, [NOTCH] SWITCH and CONTROL, INB] SWITCH, and [AGC] CONTROL do not function in this mode. 2) Press the (POWER] SWITCH IN to turn ON power. 1s The FREQUENCY DISPLAY and METER light up. 3) Push the [FM] MODE SWITCH to select this mode. The “FM INDICATOR appears.4) Adjust [AF] CONTROL. 4) Turn the [AF] GAIN CONTROL to a suitable listening level 5) Adjust [SQL] CONTROL. 5) Turn the [SQL] CONTROL clockwise until the noise is quieted, ecw SQUELCH: If closed, the squelch mutes all noise from the a ‘speaker when no signal is received. This is useful while waiting for another station to call 6) Sslect the METER SWITCH and turn the 6) Select the METER SWITCH and turn the TUNING CONTROL to TUNING CONTROL, receive an FM signal. LS+RF = Smeter position = C+ ALC = Center meter position #Smoter ‘+When tuning an FM signal, tune for maximum signal strength a¢ indicated on the meter in order to receive the clearest audio signal ‘*center mator ‘The Center meter is useful for checking if the receive frequency is being received at maximum efficiency. Press the METER SWITCH OUT to the [S + RF] position to activate the Center 7) The [RF GAIN] CONTROL functions as a variable attenuator ia FM mode. Maximum counterclockwise rotation attenuates signals by 2008. *# Tone Squetch operation ‘This is a function created by an optional UT-34 TONE SQUELCH UNIT. It is designed for interference-free communications with other stations equipped with a similar system, ‘The following transmitting procedures should only be started after the steps in SECTION 5 - 2 (1) FM receiving have been completed, 1) Switeh to transmit mods, 1) Select transmit mode with either the [XMIT] on the front panel Puan or (PTT] SWITCH on the microphone. Siow *@ Fann #The red TRANSMIT INDICATOR lights up whenever the 1C-275H is placed in transmit mode. Push (MIT) SWITCH IN 02) Adjust [RF PWR) CONTROL, Fm segic cain ‘SFM REPEATER OPERATION 1) Push [DUP] swiTCH, Fama 2) Site 0 rani pun lert} -6 sare Fras 5-3 SSB OPERATION (1) 888 receiving 1) Set the switches and controls 2) Turn power ON, 2) Push either [USB] or [LS8) SWITCH. fives DO } V4 ‘5} Adjust [AF] GAIN CONTROL. ce 6 aS 2) Adjust the [RF PWR] CONTROL to obtain a suitable output power level. 3) Speak into the microphone using your normal voice level. Mic gain can be adjusted by using the [MIC GAIN] CONTROL. ‘* The meter needle indicates the relative carrier power when the METER SWITCH is in the OUT [S+RF] position. However, the needle does not move in time with your voice modulation in FM mode. Following are the basic procedures for duplex operation. Refer to SECTION 6-6 OUPLEX (SPLIT FREQUENCY) OPERATION {(p. 29) for further information. 1) Push the [DUP] SWITCH alternately to select the desired duplex diteetion. [DUP-] + [DUP+] + No indication (SIMPLEX) 2) Select the transmit mode. ‘she receive frequency changes to the displayed transmit fre quency. The degree of frequency change (offset frequency) can be programmed. 1) Set the switches and controls as shown in SECTION 5 -1 2) Press the [POWER] SWITCH IN to turn ON power. ‘* The FREQUENCY DISPLAY and METER light up. 3) Push either the [USB] or [LSB] SWITCH to select the desired mode. '* The USB mode is commonly used in the 144MHz band. 1» The “USB” or “LSB INDICATORS appear. 4) Push the [AGC] SWITCH IN to select the AGC FAST position if the reoeive signals are fading rapidly. 5) Adjust the [AF] GAIN CONTROL to a suitable listening level. =2-6) Turn [SAL] CONTROL i) = 7) Turn TUNING CONTROL, NOISE BLANKER OPERATION | | ee “SPASSBAND TUNING OPERATION GD “NOTCH FILTER OPERATION vas (2) $88 transmitting 1) Seiteh to tranemit ert) "6 wires “rm Puan [xan] SWITCH 2) Set METER SWITCH to the ALC position vt Fron a (8 26/4 6) Turn the [SQL] CONTROL clockwise until the noise from the speaker is quieted, SQUELCH: If closed, the squelch mutes all noise from the speaker when no signal is received. This is useful ‘while waiting for another station to call, 7) Turn the TUNING CONTROL and search for a signal, Tune across the signal to its peak position to receive the clearest audio in the signal ‘* The Passband Tuning, Notch Filter and Noise Blanker functions are very helpful in getting better readability when operating while receiving interference or pulse-type noise, This is & useful function that reduces pulse-type noise such as thet generated by automobile ignition systems. See page 28 for more detailed information, This function reduces or eliminates interference, See page 31 for more detailed information. This function can be used to reduce or eliminate interfering heterodyne signals that fall within the passband of the receiver. ‘See page 31 for further information. The following transmitting procedures should be followed only after completing the operation steps in 6 -3 (1) $$8 receiving 1) Select the transmit mode with either the [XMIT] on the front panel or [PTT] SWITCH on the microphone. The red TRANSMIT INDICATOR lights up whenever the IC-275H is placed in transmit mode. 2) Set the METER SWITCH to the ALC position. Speak into the microphone using your normal voice level. 3) Adjust the {MIC GAIN] CONTROL for a meter reading within ‘the ALC zone on voice peaks. — —22-4) Agjust [RF PWR] CONTROL. “*SPEECH COMPRESSOR OPERATION ) 5-4 CW OPERATION (1) CW receiving 41) Set the switches end controls 2 ‘Turn power ON, 3 Push (OWN) SWITCH, ) . Ae ~ (5 6) a= 7 e 3 4) Adjust the [RF PWR] CONTROL to a suitable output power level ‘Talk power can be increased over long distances by using this func: tion, See page 27 for further information. 1) Set the switches and controls as shown in SECTION 5 - 1 2) Press the [POWER] SWITCH IN to turn ON power. «The FREQUENCY DISPLAY and METER light up. 3) Push the [CW/N] MODE SWITCH once or twice to alternately select CW or GW-Narrow mode. The “CW” INDICATOR appears for a normal bandwidth, The “CW-N" INDICATOR appears for a narrow bandwidth, and is valid when the optional FL-83 CW NARROW FILTER is installed, NOTE: No sound is emitted unless an optional FL83 CW f NARROW FILTER Is installed when CWNarrow mode Is selected. 4) Push the [AGC] SWITCH IN to select the AGC FAST position, 5) Adjust the [AF] GAIN CONTROL to a suitable listening level 6) Turn the [SQL] CONTROL clockwise until noise is quieted and the squelch closes SQUELCH: If closed, the squelch mutes ll noise from the speaker when no signal is received. This is useful while waiting for another station to call. 7) Turn the TUNING CONTROL and search for a signal. Tune across the signal until the needle peaks while listening for the clearest audio signal. ‘shen receiving CW signals with an 800H? tone, the recaive and ‘transmit frequencies of the station making contact are the same. -23-‘NOISE BLANKER OPERATION Cab IC IC "ASSBAND TUNING OPERATION @) NOTCH FILTER OPERATION oe (2) OW transmitting 1) Conneer GW key, 2) Select tranemit mode, ‘This useful function reduces pulse-type noise such as that generated by automobile ignition systems. See page 28 for detailed informa tion ‘This function is designed to reduce or eliminate interference, See page 31 for detailed information, ‘This function may be used to reduce or eliminate interfering heterodyne signals that fall within the passband of the receiver See page 31 for detailed information, ‘The following transmitting procedures should be started after first, beginning the steps in SECTION 5 - 4 (1) CW receiving 1) Insert the CW key plug into the KEY JACK on the rear panel i aa | 2) Select the transmit mode with the [XMIT] SWITCH or [BK-IN] SWITCH on the rear panel, Refer to BREAK:IN OPERATION ‘on page 25. *The red TRANSMIT INDICATOR lights up whenever the 1C.275H is placed in transmit mode, 3) Operate the CW key. # The meter movement indicates that a signal is being transmitted ‘* CW sidetone (described below) is emitted from the speaker. 4) Adjust the [RF PWR) CONTROL to obtain suitable output power. ‘An 800H2 sidetone oscillator is provided to monitor keying when ‘operating in CW mode, This tone is also audible in receive mode and can be used for CW code practice or adjustment of the keyer. ‘*The [CW SIDETONE] CONTROL varies the volume of the oscil lator tone. This control is located on the rear panel of the trans ceiver. The transceiver [AF] GAIN CONTROL also varies the volume, 24BREAKIN OPERATION 5-5 PACKET AND AMTOR OPERATIONS 5-6 RTTY OPERATION The IC-275H has both semi break-in full break-in capability. This means the transmit/receive switching is performed automatically by the transceiver whenever the keying starts or stops, The receive to transmit switching time is, practically speaking, instantaneous, whereas the transmit to receive switching time may be varied ‘through adjustment to suit an individual's keying speed. 1) Slide the [BK-IN] SWITCH to set either the semi break-in oF full break-in operation, This switch is located on the rear panel. [SEMI]: Semi break-in operation [FULL]: Full break-in operation 2) Place the [XMIT] SWITCH in the receive position (OUT). 3) Begin sending with the CW key and the transceiver will switch between transmit and reesive automatically, 4) Set the transmit release delay time to suit your keying speed by adjusting the [DELAY] CONTROL when operating with semi break-in. ‘NOTE! The optional AG-26 cannot function when the (BKIN] | ‘SWITCH ic in the [FULL] position even if the preampli- ‘fiers turned on. PACKET and AMTOR operations require a rapid transmit and receive switching time since they are handshaking communications The IC-275H requires only Smsec. for switching when the [DATA] ‘SWITCH on the front panel is used. 1) Connect a terminal unit and any external equipment if required ‘See page 16 for proper interconnections. 2) Set the switches and controls as explained in SECTION 5 - 1 3) Turn power ON. 4) Set mode either to [FM], [USB], or [LSB]. CW mode is not acceptable for data communications. 5) Push the [DATA] SWITCH ON. The “DATA” INDICATOR appears. 8) Enter commands or data to operate your terminal unit with the 1c-275H. With the 1C-275H, RTTY contacts may be enjoyed by using AFSK (Audio Frequency Shift Keying). The demodulator used should have 2125/2205He or 1700/2125He filters for 170H2 or 425Hz shift ‘operation. 1) Connect & terminal unit and any external equipment if required, See page 16 for information regarding interconnections. 2} Set the switches and controls as explained in SECTION 5-1 3) Turn power ON, 4) Set the mode to [LS8] 5) Begin sending with your ATTY terminal unit. ~26-‘FREQUENCY READOUT USING AN AFSK GENERATOR 5-7 SSTV OPERATION When operating in RTTY, there is a difference between the dis: played frequency and the actual operating frequency. Receiving: Assuming the demodulator mark frequency is 2125Hz and the space frequency is 2295Hz: ( ‘Transmit frequency of Monitor Display AFSK keying signal f CCI) pin 4 AFSK receive signal ACCIt) pin 5 sAn RTTY Terminal Unit for AFSK operation can also be con nected easily. ‘Slow Scan Television operation is also possible with the IC-275H, ‘*Connect the CAMERA OUTPUT on your SSTV unit to the ACC(1) CONNECTOR pin 4 or MIC CONNECTOR pin 1 1*The audio output signal is available from pin 5 on the ACC(1) SOCKET. The output level can be changed by S2 on the MAIN UNIT. ‘© Soe page 16 for AGC(1) SOCKET information. 266. FUNCTIONS OPERATIO 6-1 SPEECH COMPRESSOR ‘The IC-275H has a low distortion, AF speech compressor circuit OPERATION which provides greater talk power by improving the intelligibility of the transmitted signal over long distances. 1) Set [COMP] SWITCH 0 ON position. 1) Set the switches and controls as shown in the table. SWITCH/EONTROL [POSITION] MIC GAIN Center (12 o'clock) RF POWER Max. CCW | COMP ON (in) 2) Switch to transmit and speak into the mi, 2) Switch to transmit and speak into the microphone using your 3) Adjust [COMP LEVEL] CONTROL if needed, 3) The compressor gain can be adjusted by the [COMP LEVEL] SPEECH COMPRESSOR LEVEL CONTROL on the rear panel ‘*To increase the gain, rotate the [COMP LEVEL] clockwise. o--| e el Amun © 6-2 PREAMP SWITCH OPERATION — This switch is activated only when an optional AG-25 WEATH. ERPROOF 144MHz PREAMPLIFIER UNIT is installed. AG-25 improves S/N ratio and receiver sensitivity and makes DX-com munication possible. The [PREAMP] SWITCH turns the receiver preamplifier ON and OFF. 1) Push (PREAMP) SWITCH, 1) Push the [PREAMP] SWITCH. 2) Sitch to transmit, 2) Push either the microphone {PTT] SWITCH or [XMIT] SWITCH ‘to automatically switch the AG-25 WEATHERPROOF 144MHz PREAMPLIFIER UNIT to be through. Transmit signals will bypass the preamp circuit NOTE: The optional AG-25 is designed to operate at normal ‘ansmit and receive switching speeds so the [PREAMP] | SWITCH, rather than the high speed {DATA} SWITCH, should be used during normal operation, ‘The preamp function does not function when the [DATA] SWITCH is turned ON (IN position}. -27-6-3 AGC OPERATION 6-4 NOISE BLANKER (NB) OPERATION 1) Pash [NB] SWITCH. Cj IE IEA ia V# 6-5 SUBAUDIBLE TONE ENCODER AND 1750Hz TONE CALL OPERATIONS (1) Subaudible tone encoder operation (2) 1750H2 Tone Call operation ‘The IC-275H has a fast attack/slow release AGC system which maintains @ peak voltage of a rectified IF signal from the 1F ampli fier circuit for a brief period of time. “This circuit prevents irritating background noise from being heard during the short pauses in speech. The damping effect of the AGC therefore allows accurate Smeter readings to be taken of peak IF signal strength. 1) For normal SSB reception: ‘Select the SLOW (QUT) position. For CW reception or for SSB signals with short interval fading: Select the FAST (IN} position, 2) The AGC function does not work in FM mode, ‘This operation effectively reduces unwanted pulse-type noise from outside sources such as ignition noise from vehicles. 1) Push the [NB] SWITCH, 2) The noise bianker may not work as well when strong signals are fon nearby frequencies or when the noise is continuous rather than pulse-type. Subaudible Tone Encoder (IC-275H U.S.A., Australis versions): The builtin tone encoder allows access to repeaters which require a subaudible tone superimposed on the transmit signal 11750H2 Tone Call (IC-275H Europe, Sweden versions): [An audible 1750Hz tone signal may be generated for the purpose of accessing repeaters. ‘The tone frequency can be programmed into each memory channel independently. 1) Select @ memory channel you want to program the tone fre {quency in for the VFO modes or MEMORY CHANNEL mode. 2) Push the [TONE] SWITCH to turn ON the tone encoder function, 3) Push the [SET] SWITCH and rotate the TUNING CONTROL to select the desired tone frequency. 4) Push the [SET] SWITCH again to program the tone frequency. ‘The [TONE] SWITCH alternately turns ON and OFF the tone encoder function. Push the [TONE] SWITCH and hold for approximately 1 ~ 3 seconds to open a repeater. -28-6-6 DUPLEX (SPLIT FREQUENCY) OPERATION (1) Duplex operation using the fixed 600kH2 offset frequency. 1) Select 145.6000MHz ond FM MODE. 195.600.0 13 2) Push [OUP] SWITCH to et the -DUPLEX. 5600.0 13 23) Teansmit Transmit frequency a i 4) Push [CHK] SWITCH, 5) Push [DUP] SWITCH 10 cancel the duplex mode. 456000 13 DUP" aappears — ‘The purpose of the duplex function is to allow an operator the option of transmitting and receiving on two different frequencies. ‘The 1C-275H provides duplex operation using either of the follow: in two methods: (1) Operating on @ fixed 6OOkHz frequency or user-programmed offset frequency. (2) Operating on VFO A and VFO B with the [SPLIT] SWITCH. Following are examples for duplex operation using 145,6000MH:z for receiving and 145.0000MHz for transmitting with a GO0kHz fixed offset frequency on FM mode ° Frame 2 2 1) Select 145.6000MHz with the TUNING CONTROL and push the [FM] SWITCH. 2) Push the [DUP] SWITCH to set the -DUPLEX mode. "DUP" appears on the FREQUENCY DISPLAY. 3) Push either the [XMIT] or [PTT] SWITCH to transmit. # The FREQUENCY DISPLAY should indicate 145.0000MHz for ‘transmitting, «® You are now receiving on 145,6000MHz and transmitting on 145,0000MHz, 44) Push the (CHK] SWITCH to check the repeater input frequency, if needed. 5) Push the [DUP] SWITCH until either “DUP—" or “OUPS" disappears from the FREQUENCY DISPLAY, cancelling the duplex mode. og(2) Resetting the offset frequency 1) Push [DUP] SWITCH, 2) Push (SET) SWITCH. o6oco8 23) Set the offset frequeney For B5OKHe 8850.0 44) Retuen to normal operating mod 456000 73 (3) Duplex operation using contents of VFO A and VFO B (SPLIT operation) 1) Set VFO A mode and program 145,9500MH2, 5.9500 73 2) Set VFO B mode and program 144.5500MH 3) Return to VFO A mode 4) Push [SPLIT] SWITCH, 5) Transmit 6) Recsiving 145.9500 Transmitting : 144,6500MH2 45.9500 93 45509 “93 The offset frequency can be reset for use in duplex operation, Following is an example for resetting the offeet frequency at 850kHz, 1) Push the [DUP] SWITCH to set the duplex mode. 2) Push the [SET] SWITCH. The subaudible tone function (U.S.A.,. Australia versions) or Tone Call function (Europe, Sweden versions should be turned OFF when resetting the offset tre quency, 3) Rotate the TUNING CONTROL to “0.8500" for the desired offset frequency of 850kH2, 4) Push one of the following switches to return to the normal operating mode: (TONE], [DUP] or {CHK] Duplex operation is possible using the contents of VFO A and VFOB. Following is an example for 145.9500MHz for receiving and 144.5500MHz for transmitting on duplex (split frequency) opera- tion 1) Push the [VFO] SWITCH to set the transceiver in VFO A mode and set a receive frequency of 145.9500MHz with the TUNING CONTROL, 2) Push the [VFO] SWITCH to set the transceiver in VFO B mode land set a transmit frequency of 144.5500MHz with the TUNING CONTROL, 3} Push the (VFO] SWITCH again to return to VFO A mode, 4) Push the [SPLIT] SWITCH to enter the split frequency operation. + "SPLIT" appears on the FREQUENCY DISPLAY. 5) Push either the [XMIT] or [PTT] SWITCH to transmit. 6) You are now receiving on 145,9500MHz and transmitting on 144.5500MHz. Push the [VFO] SWITCH once again to receive ‘on 144,5500MH? and transmit on 145.9500MH2. Each VFO stores the operating mode in addition to the operating froquency. This allows crossmode contacts to be easily made, made ~306-7 DATA SWITCH OPERATION 6-8 PASSBAND TUNING (PBT) OPERATION This switch allows you to freely operate digital communications such as AMTOR or PACKET with time delay. ‘The lockup time is approximately § milliseconds when using the [DATA] SWITCH. ‘* The [DATA] SWITCH does not function in CW mode, 1) Connect the terminal unit to the 1C-275H properly. NOTE? See page 16 and your terminal unit instruction manual ‘regarding terminal unit connections for digital com- ‘munications. 2) Select a mode switch and push the [DATA] SWITCH. # DATA” appears on the FREQUENCY DISPLAY, Passband Tuning is a system designed to electronically narrow the bandwidth (electivity) of frequencies that will pass through the receive erystal filter NOTE: Pessbend wining does not funct ino effect in CWN mode. 6-9 NOTCH FILTER OPERATION 1) Push [NOTCH] FILTER SWITCH. 2) Adjust [NOTCH] FILTER CONTROL, This circuit provides high attenuation at one particular frequency in the IF passband, It may be used to reduce or eliminate interfering heterodyne signals that fall within the passband of the receiver 1) Push the [NOTCH] FILTER SWITCH to the ON position (IN. 2) Adjust the [NOTCH] FILTER CONTROL to minimize inter- ference, ‘* Notch filter characteristics6-10 RIT OPERATION 1) Push [RIT] SWITCH ON, Receive: 144.6953MHE Transmit 144.695]MHe RIT" appears 2) Rotate [RIT] CONTROL Cw, Foceive : 144.7019MH2 Tranemit + 144.6053MH2 Increases the shite fequeney 144695.9 65 73 3) To clear the RIT shite, push [RIT-CL] SWITCH. Receive: 144.6959NH2 Transmit 144.6953MH2 1446959 a0 73 "The sil value rset wo 4) To tn OFF the RIT, push [RIT] SWITCH. 446959 By using the RIT circuit, itis possible to shift the receive frequency up to 9.9kHz to either side of the transmit frequency without moving the transmit frequency. This is useful for fine tuning stations which transmit using off frequency or for compensating for frequency drift, 1) Push the [RIT] SWITCH to activate the RIT circuit ‘2 "RIT” and the amount of shift are displayed. 2) Rotate the [RIT] INCREMENTAL TUNING CONTROL in the (+) direction to raise the receive frequency, or in the (—) direc tion to lower the frequency, 3) To clear the RIT shift frequency, push the [RIT-CL] SWITCH, ‘eThe shift value resets to “0.0" and the receive and transmit frequencies become the same whether the RIT circuit is ON or OFF. 4) To turn OFF the RIT function, push the [RIT] SWITCH agai. *“RIT” and the amount of shift disappear from the FRE QUENCY DISPLAY. ‘* The transmit and receive frequencies are the same as indicated on the FREQUENCY DISPLAY. a n0 @® ~326-11 MICROPHONE UP/DOWN OPERATION up pow uP/oown err switch ‘ON-OFF SwitcH (1) Frequency controt (2) Memory channel selection 6-12SWR READING OPERATION This up/down function is useful for changing the operating fre- quency when using the VEO mode or when using the MEMORY CHANNEL mode. Microphone UP/DOWN ON-OFF SWITCHES: OFF: The [UP] SWITCH and [ON] (down) SWITCH on the ‘microphone are disabled to eliminate accidental frequency ‘or memory channel changes. *ON: The [UP] or [DN] SWITCH can be used to change operat- ing frequencies. 1) Each push of the [UP] or [DN] SWITCH on the supplied micro: phone changes the operating frequency one increment up oF down, respectively. 2) Holding either switch down changes the operating frequency continuously in the same manner as the TUNING CONTROL. 1) When using the MEMORY CHANNEL mode, the memory channel may be changed with the microphone up/down switches, 2) The memory channel or the displayed memory channel number change continuously if the microphone switches are held down, Tne IC-276H has a builtin SWR meter to check antenna matching a5 an aid to avoiding problems caused by high SWR, 1) Set the METER SWITCH on the front panel to the [S+RF] position. 2) Set the [TX-METER] SWITCH on the rear panel to the [SET] position. 3) Select FM mode. 4) Rotate the [MIC GAIN] CONTROL fully CCW. 5) Push the [XMIT] SWITCH to the TRANSMIT (IN) position, 6) Adjust the [RF PWR] CONTROL located on the front panel to move the meter needle to “SET” on the SW scale. 7) Set the [TX-METER] SWITCH to “SWR the SWR scale Read the SWR from 8) If the SWR is less than 1.5, the matching condition between the 1C-275H and your antenna is good. oS O00 e0°0 OoMEMORY AND SCANNING OPERATION 7-1 VFO A AND VFO B SELECTION ‘The 1C-275H has ninety-nine memory channels. One frequency. the operating mode, the subaudible tone frequency, VFO A/B, and the duplex condition may be assigned to each memory channel whether the transceiver is in VFO mode or MEMORY CHANNEL mode. 1) VFO A and VFO B can be solected by pushing the (VFO) SWITCH alternately 2) The parameters in VFO A and VFO B can be made the same by pushing the [A = B] SWITCH, Push (VFOI 145.6000 <>] Mue9s3 Lo renin Push [VFO] 145.600.0 |<>/omsseeae ™; 7-2 MEMORY CHANNEL AND VFO SELECTION 1) Push the [MEMO] SWITCH to select the MEMORY CHANNEL, mode. MEMO" appears on the FREQUENCY DISPLAY. 2) Rotate the [MEMO] CHANNEL SELECTOR CONTROL to select any of the memory chan. ‘When memory channels not yet programmed are selected, only docimal points appear on the FREQUENCY DISPLAY, 3) Push the [VFO] SWITCH to return to VEO A or VFO B mode selection. Push [MEMO} | >| Masase Rotate [MEMO i> 2)m 3 /MBEE) 99 \@ P {Ie P2/ Push [VFO] 145.8308 33) (> | 56000" 99 34-7-3 MEMORY DATA TRANSFER 1) When the transceiver is in VFO mode, the frequency and modes stored in the memory channel displayed are transferred to the selected VFO. 2) When the transceiver is in MEMORY CHANNEL mode, the frequency and mode are transferred to the VFO used immediately before transferring to MEMORY CHANNEL mode, a a: ee ee a es ese fe ga eee MEMORY DATA TRANSFER function will not be ee os eeAaT eRaaa 56008 99] >| 458300" 39] : 3 45353] > | i4ys3s3” 7-4 PROGRAMMING MEMORY Any frequency, operating mode, subaudible tone frequency, Pe eg ae rae come erat : 1) Select operating parameters. 1} Set the frequency and mode for 145,5000MHz and FM using the 195.508.8 ! aw ae venga, Seonontel | 1455000 88 Memory Channel 88, ‘*When the programming is successful three short beep tones will be emitted 4) To check the memory channel contents, push the [MEMO] SWITCH, # The contents of the selected memory channel are displayed,7-5 PROGRAMMING THE CALL CHANNEL (1) Programming the CALL CHANNEL 1) Hold down (CALI SWITCH and set the call frequency. 2} Sex the parameters 458800 © 23) Push (MW SWITCH, (2) Recalling CALL CHANNEL information 1) Push (CALL) SWITCH, 2) The “Cand eal frequency appear S$eeag oc 3) Push either [VFO] or MEMO] SWITCH 10 return to VFO or MEMORY CHANNEL mode 7-6 MEMORY CLEARING 1) Push [MEMO] SWITCH. 2) Select the memory channel to be cleared. 3) Push IMCL} SWITCH. _ E 99 45.8308 99 ‘This CALL CHANNEL is useful for quickly recalling and changing frequently used frequencies from any operating mode, 1) Hold down the (CALL] SWITCH and set the desired call fre ‘quency by rotating the TUNING CONTROL, then release the [CALL] SWITCH. 2} Set the needed parameters such as operating mode, subaudible tone frequency, and duplex condition using each switeh, 3} Push the [MW] SWITCH until three beep tones are emitted for storing these parameters. CALL CHANNEL information can be recalled, 1) Push the [CALL] SWITCH. 2) "C" and the programmed call frequency appear on the FRE. QUENCY DISPLAY. 3} Push either the [VFO] or [MEMO] SWITCH to return to VFO or ‘the MEMORY CHANNEL mode. This function is used to clear the information in each memory channel 1) Push the [MEMO] SWITCH to enter MEMORY CHANNEL mode. 2) Select the memory channel to be cleared by rotating the [MEMO] CHANNEL SELECTOR CONTROL. 3) Push the [M-CL] SWITCH until three beep tones are emitted from the speaker, # The memory channel is now vacant. 36 -7-7 SCANNING OPERATION ‘SCAN FUNCTION NOTES (1) SCAN SPEED SWITCH (2) ADJUSTING SQUELCH CONTROL (3) SCAN TIMER (1) Memory sean 1 Program memory channels 2) Agjust [SAL] CONTROL. 3) Push (MEMO) SWITCH 5] The scan stops when © receive signal opens 6) Use [SCAN] SWITCH to manually stop the ‘The IC-275H comes equipped with four scan functions, providing ‘tremendous scanning versatility at the touch of just a few switches, ‘SCAN TYPE OPERATION ] MEMORY | Scans all MEMORY CHANNELS containing CHANNEL | information while skipping memories in | SCAN blank status | Repeatedly scans between two user-PRO- PROGRAMMED | GRAMMED frequencies in the scan range SCAN using independent memories P1 and P2 for storage of frequency data, - SELECTED | Repeatedly scans _all_ memory channels ‘MODE Containing frequencies in the same MODE as. | MEMORY SCAN | the displayed frequency. Scans all specified memory channels while skipping unspecified channels and those in blank status SKIP SCAN Le Before starting scanning operations, please read the following additional information and preset the switches and controls. See SECTION 9 INSIDE VIEWS (p, 42) for switeh locations, Switches the scan speed in any scan mode. Slide the switch to the position for the desired speed. Adjust the [SQL] CONTROL to quiet the noise output from the speaker since the sean will not stop without setting the squelch, When a signal is received, the scan stops and then starts again after 3 oF 10 seconds. These times depend on the type of signal received. 3 seconds 10 seconds A signal of short duration, A signal of tong duration. ‘This function is used to automatically scan all programmed memory channels, 1) Program the desired frequencies into memory channels. See page 35 PROGRAMMING MEMORY CHANNELS. 2) Adjust the [SQL] CONTROL to quiet the noise output from the speaker. 3) Push the [MEMO] SWITCH to select MEMORY CHANNEL mode. 4) Push the [SCAN] SWITCH to start the scan. ‘+ "SCAN" appears on the FREQUENCY DISPLAY. ‘*The IC-275H begins scanning the programmed channels from the lowest channel towards the highest channel '5) The scan stops for approximately 3 or 10 seconds after a receive signal opens the squelch, then resumes scanning 6) Push the [SCAN] SWITCH to stop the scan function manually. Turning the TUNING CONTROL also stops the scan. # “SCAN” disappears.(2) Programmed scan 1) Store the scan limits in Memory Channels Pt and P2, 55000 FP} 1458800 Pe 2) Select the desired mode, 3) Adjust (SAL) CONTROL, 4) Push [SCAN] SWITCH to start sean '5) Tho squelch opens when a signals recived 6) Push [SCAN] SWITCH to cancel scanning ‘manual (3) Selected mode memory sean 1) Store desired frequencies 2) Push [MEMO] SWITCH. 23) Adjust (SQL] CONTROL. 4) Push one of the four MODE SWITCHES, ‘The purpose of this scanning function is to monitor 2 particular section of the band, ‘*Programmed scan Higher freaue ff P2 | frequency Frequency Endless 1) Store the frequencies of the HIGH and LOW limits of the desired scanning range in memory channels P1 and P2 ‘Turn the [MEMO] SELECTOR CONTROL to select Memory Channels P1 and P2. See page 35 PROGRAMMING MEMORY ‘CHANNELS. ‘©The scan begins from the LOW limit of the range regardless of which channel has the lower frequency stored. 2} Select the desired mode. 3) Adjust the (SQL] CONTROL to quiet the noise output from the speaker. 4) Push the [SCAN] SWITCH to start the sean. The scanning rate depends on the [TS] SWITCH position. ‘* "SCAN" appears on the FREQUENCY DISPLAY. 5) The squelch opens when a signal is received. After approximately 3 or 10 seconds the scan resumes seanning 6) Push the [SCAN] SWITCH while the scan is operating or during the 3 or 10 second delay period to manually cance! the scan. ‘Transmitting or rotating the TUNING CONTROL also cancels ‘the scanning function The purpose of this scan is to selectively monitor memory channels, which contain frequencies programmed with the same mode: FM, USB, LSB or Cw, 1) Store the desired frequencies with mode into memory channels. 2) Push the [MEMO] SWITCH to select MEMORY CHANNEL mode. 3) Adjust the [SOL] CONTROL to quiet the noise output from the speaker, 4) Push one of the four MODE SWITCHES to select a receive mode. -385} Push [MODE-S) SWITCH, 6) Push [SCAN] SWITCH. 7) The squelch opens when a signal s received 8) Push [SCAN] SWITCH to manually stop the (4) Skip sean 1 Store desired frequencies Push [MEMO] SWITCH. a Select MEMORY CHANNELS you do not want 4) Push (SKIP) SWITCH, 459800 46 Adjust [SOL] CONTROL. 5 6 Push [SCAN] SWITCH b ‘The squelch opens when a signal received 7 Use [SCAN] SWITCH to manually stop the 5) Push the [MODES] SWITCH to set the SELECTED MODE MEMORY SCAN. 6) Push the [SCAN] SWITCH to start the scan, ‘*/"SCAN" appears on the FREQUENCY DISPLAY. ‘If a longer beep tone is emitted, no frequency with the desired ‘mode is stored in the memory channels. 7) The squelch opens when a signal is received. After approximately 3or 10 seconds the scan resumes. 8) Push the (SCAN] SWITCH to stop the scanning function manual ly. Turning the TUNING CONTROL also stops the scan. SKIP SCAN repeatedly scans specific memory channels chosen by the user. Skip sean. MEMORY cH cra. Gad renee oni -ch.99 «—cH.98-——${fc4.52--cH.51 + cH s0 1) Store the desired frequencies with mode, ete., into a memory channel 2) Push [MEMO] SWITCH to select the MEMORY CHANNEL mode. 3) Select MEMORY CHANNELS you do not want to receive in during scanning operations by using the [MEMO] SELECTOR CONTROL, 4) Push the [SKIP] SWITCH to program a frequency to be skipped into the memory channel ‘*""SKIP" appears on the FREQUENCY DISPLAY. 5) Adjust the [SQL] CONTROL to quiet the noise output from the speaker, 6) Push the [SCAN] SWITCH to start the scan. ‘SCAN appears on the FREQUENCY DISPLAY. 7) The squelch opens when a signal is received. After approximately or 10 seconds the sean resumes, 8) Push the [SCAN] SWITCH to stop the scanning funtion manu ly, Turning the TUNING CONTROL also stops the scan, ~398, MAINTENANCE AND ADJUSTMENT 8-1 MAINTENANCE (1) Cleaning (2) Fuse PAunit fue replacement (41 APP ‘Shiela (3) Backup battery (4) Resetting the internal microprocessor (5) Automatic protector circuit If the transceiver becomes dusty or dirty, wipe it clean with @ dry, soft cloth. Avoid the use of strong cleaning agents such as benzine fr alcohol as they may damage the surfaces. If the fuse blows or the transceiver stops functioning, track down the source of the problem if possible, and replace the damaged fuse with @ new, rated fuse. PAunit fuse. . F.G.M.B, 125V 3A DC eabie '=DC line fuse replacement The IC-275H uses an advanced, highly reliable microprocessor chip. The purpose of the battery is to provide power to the micro: processor so it retains all memory information during power failures, (or when the unit is unplugged or turned OFF. ‘The usual life of the backup battery exceeds five years. It is advisa ble to monitor the battery carefully and replace it if there are repeated cases of display malfunction, ‘©The transceiver transmits and receives normally if the backup battery is exhausted but the transceiver cannot memorize fro quencies NOTE: Battery replacement should be done by an authorized ICOM Desler or ICOM Service Center. Occasionally, the FREQUENCY DISPLAY may display erroneous information, When this problem occurs, turn OFF power to the IC-275H, wait 4 few seconds and turn ON power again, If the problem persist, perform the following procedure. Nott ‘Ail information. programmed in memory channels will be cleared if the transceiver Is reset. 1) Turn power OFF, hold down the [MCL] SWITCH, and turn power ON. 2) The IC-275H is now reset A builtin protector circuit automatically holds transmit output power at SOW when operating the transceiver continuously for a while at maximum power. This protects the final transistors from ‘overheating 40-8-2 ADJUSTMENTS (1) Brake adjustment (2) Display tight dimmer adjustment (3) Beep sound te ‘The TUNING CONTROL tension may be adjusted to the operator's preference. The screw adjustment is located on the bottom side of the transceiver cabinet below the TUNING CONTROL. The method for adjustment is as follows: 1) Rotate the TUNING CONTROL continuously and smoothly in one direction, 2) Adjust the brake adjustment screw either CW for tighter tension, or CCW for looser tension as desired. ‘Brake adjustment Agiustment hole ‘The IC-275H has an illuminated FREQUENCY DISPLAY for easy reading in dim or no light situations. The light intensity may be varied to suit the ambient light conditions, er ae Be ‘The level of the beep sound which is emitted when the specified switches are pushed can be adjusted by R348 on the MAIN UNIT. COW rotation of R348 increases the sound level See SECTION 9 INSIDE VIEWS for the location of R348,9. INSIDE VIEWS MMAIN AND RF-YGR UNITS S1 Moduator Sensitivity Selector Smiten 100m J] 3mV 5 Pore selector Sitch ‘ y ‘ a Sap to eg to co ‘ i aa he ‘$2 AF Selector Switch pve sso ewe Fut eal ed Ene eos a 24566 Mee Ad EW Mee Fl See A R259 High Power Adj. 7 Se IB6 BFO Check Point Teer enone. C119 BFO LSB Adi, 173 EM Mic Gain Adi Lar aFo ewin) Adi R221 FM Meter Ad MAIN UNIT. 1.23 FM Diseriminator Ad L20 BF use Adi R287 RF Meter Adj REYGR UNIT R18 Dimmer Adi 1 Scan Speed Switch Fe By som $3 Remote Control Detoult Swatches Beckup Battery vco UNIT 22 PLL Reference Freq —Locie unit PLL untT DS (Direct Distal ‘Synthesizer UNIT —42—10. OPTION INST, TIONS TRANSCEIVER 1) Remove the top cover. The PA UNIT is located here, DISASSEMBLY 2} Remove the bottom cover, The MAIN and AF-YGR UNITS are located here. 3) Remove the PA UNIT, The PLL and LOGIC UNITS are located underneath the PA UNIT. | MAIN AND RF-YGR UNITS SIDE GW Narrow Fer MPLL AND LOGIC UNITS SIDE P8 (3 pins) [Space for UT-36 °2 (5 pins) — Voice Synthesizer Unit Space for UT-34 “Tone Sauelch Unit Space for CRG Connectors for UT ee Hignstability Pas le pins, P47 [5 pins) Cryseal UnitmUT34 ‘The UT-34 TONE SQUELCH UNIT provides you with interference: TONE SQUELCH UNIT free communication with other stations equipped with @ Tone squelch system. ‘*The unit should be installed in the designated spot behind the internal speaker on the PA UNIT. 1) Remove both the top and bottom covers. Space for UT-34 ‘Speaker code 2) Remove the PA UNIT. 3) Install the UT-34 and connect P46 (6 pins) from the LOGIC/ FRONT UNITS toJ1 on the UT-34 4) Connect P47 (5 pins) from the LOGIC/FRONT UNITS to J2 on the UT-34, Replace the PA UNIT and covers | 5) Refer 10 the UT:34 instruction sheet for operating instructions. PA UNIT mUT-36 ‘The voice synthesizer announces the displayed frequency when the VOICE SYNTHESIZER UNIT [SPCH] SWITCH on the front panel is pushed. ‘*The UT-36 VOICE SYNTHESIZER UNIT should be installed on the bottom side as shown in the diagram. 1) Remove the top and bottom covers. PA UNIT 2) Remove the PA UNIT. 3) Remove the protective paper from the back of the UT-36 to expose the adhesive strip, and install the unit in the location shown in the bottom view of the transceiver 4) Connect P8 (3 pins) from the LOGIC UNIT to J2 on the UT:36, 5) Connect P2 (6 pins) from the LOGIC UNIT to J1 on the UT-36 6) Replace the top and bottom covers. Soace for UT-36 7) Refer to the UT-36 instruction sheet for operating instructions. mFL.83 ‘This FL-88 CW NARROW FILTER provides you with comfortable CW NARROW FILTER interference free CW communications, ‘The FL-83 should be installed on the MAIN UNIT. See SECTION. 10- 1 for the instalation location. FL-83 CW NARROW FILTER : +250H2/-6dB mCR64 ‘This high-stability erystal unit consists of a temperature-compensat: HIGH-STABILITY ing oven heater and a crystal unit. By replacing the original crystal CRYSTAL UNIT Unit with this unit, the total frequency stability of the transceiver will be improved. # The CR.64 should be installed on the PLL UNIT. CR64 HIGH-STABILITY CRYSTAL UNIT : 0.5ppm (-30°¢ ~ +60°c) —44—11. CAUTIONS INSTALLATION LOCATIONS environments, *D0 NOT place in excessively hot, humid, or dusty DO NOT use in direct sunlight. wanted noise or signals may be received. ™@ GROUNDING #DO NOT place near radios or TV sets where un J i DO NOT place an AC power supply on the trans- To prevent electrical shocks, TVI, BCI and other problems, be sure to ground the transeeiver through the GROUND TERMINAL. For best results, use the heaviest gauge wire or strap available and make the connection as short as possible. ONLY use a city water pipe as a good earth point if the pipe is well grounded and made of metal. NEVER use a gas pipe or electrical Conduit pipe for grounding, NEVER use a gas pipe or electrical conduit pipe for, grounding POWER SUPPLY USE the heaviest gauge wite or strap available and make the connection as short as possible. WARNING: Voltages greater than 15V DC may damage this transceiver. Check the source voltage before con- necting the power cable when using this transcoiver ‘with non-ICOM AC power supplies. =45—12. BLOCK DIAGRAM13, SPECIFICATIONS @ GENERAL Frequene coveraye USA.vesion + 140.1000 ~ 150 0000%H2 Europe version 144.0000 ~ 14600001 fmrlnvosion 144.0000 ~14500004tMe Sueconveron” 1440000 ~ 14600004 «Speciation quoraneed from 1488000 6146200042 Ree eee we men ee came test cal crmnncd Antenna impedance 502 unbalanced : Frequency staity *5ppm (10°C ~ 460°C) ; eee Aivenions 128 D0210% current dain (at 138V 00) Transmitting HIGH (100W) Aoprox. 7008 tow (0¥ fovron, BOA Aeciting At atm aud outst Apron: ‘LOA Saucenes fovron, 0A + Dimesions 24246) x 951108 mt x 2391277immt0} eseernu vata Petar ones ign ans ‘¢ Usable temperature range =10°C ~ +60°C. @ TRANSMITTER ees FM (E3858 (A331, oW (AN) + RF output power 10~ 1001 continuous adusable sModaltion stem FM Variable reactance eauerey mediation 588 Belreed modulation Maxum taquency deiion + 25kte (FM mode ‘Spurious output Hore than 608 blow peak outou power carr suppression More than 4008 blow peak output power Unworted sdebond More than 408 down with 100082 AF input Pee eee sons mRECEIVER csv sytem Dee a eno os (3), 958 (AH, cw (At) sae reqences Ist 10 7MHe (EN, $88) 1074914 (ow) ra ast (a mode «servi th SOP esd) = FM ‘Lee than 18H for 1248 SINAD Less than 0.254:V for 20d8 NOL $88, CW Less than 0.1uV for 10dB S/N ‘*Squelch sensitivity FM Less than 0.14 Sse Less than 0.56uV_ Selectivity FM 16.0kHz/6dB ——-30.0kHz/60d8, $88, CW 2.2kHz/6d8 4.2kH2/60d8 * Spurious response rejection More than 7048 1 * Audio output impedance : an | ‘Audio output power More than 2W at 10% distortion with an 822 load ‘© RIT variable range +49.99KH2. a714. OPTIONS DESK MICROPHONE EXTERNAL SPEAKER __ | N ier = om pernleowerl vec fororceiaer eae ae pn EOUAIIeEaIDEse oe IC ROROH ae, Comers a a a TONE SQUELCH UNIT uT-36 VOICE SYNTHESIZER UNIT ors cr-16 FL83 tomes crs HIGH-STABILITY CRYSTAL UNIT AOS Adapter Satellite Communication Interface Unit with 1C-475A/E ‘GW Narrow Filter (#250H2 at ~648 point) ‘Mobile Mounting Bracket ~48— AG-25 WEATHERPROOF 144MHz PREAMPLIFIER1-2 754 scHemAtIC DIAGRAMEMATIC DIAGRAMEQICcOM) tcom incorPorees VUUEMNESRE; thyeegpere @Og atICOM INCORPORATED 16-19, KAMIKURATSUKURI, HIRANO-KU, 0998 OSAKA 547, JAPAN Printed in Japan