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INSTRUCTION MANUAL

HF TRANSCEIVER

i78

This device complies with Part 15 of the FCC rules. Operation is sub-
ject to the following two conditions: (1) This device may not cause
harmful interference, and (2) this device must accept any interference
received, including interference that may cause undesired operation.

Summary of Contents for IC-78

Page 1: ...mplies with Part 15 of the FCC rules Operation is sub ject to the following two conditions 1 This device may not cause harmful interference and 2 this device must accept any interference received including interference that may cause undesired operation ...

Page 2: ...xcessively dusty en vironments or in direct sunlight AVOID placing the transceiver against walls or putting anything on top of the transceiver This will obstruct heat dissipation During mobile operation DO NOT operate the trans ceiver without running the vehicle s engine When the transceiver power is ON and your vehicle s engine is OFF the vehicle s battery will soon become ex hausted Make sure th...

Page 3: ...ve 19 Filter selection 21 Filter setting 22 Functions for CW 23 Functions for RTTY 25 Channel comment programming 27 5 SET MODE 28 33 General 28 Quick set mode items 29 Initial set mode items 31 6 EXTRA FEATURES 34 36 Instruction 34 VFO operation 34 2 Tone alarm operation 36 7 INSTALLATION AND CONNECTIONS 37 38 Opening the transceiver s case 37 Optional bracket and carrying handle 37 CR 338 HIGH S...

Page 4: ...frequency signal Rotate the control clockwise to increase the fre quency or rotate the control counterclockwise to decrease the frequency appears on the display u IF SHIFT CONTROLS SHIFT outer control p 20 Shifts the center frequency of the receiver s IF passband Rotate the control clockwise to shift the center fre quency higher or rotate the control counterclock wise to shift the center frequency...

Page 5: ...ut p 13 TXF Transmit frequency indication p 14 Selects a space and changes the editing digit during channel comment programming p 27 8 NOISE BLANKER SWITCH NB p 19 Turns the noise blanker ON and OFF The noise blanker reduces pulse type noise such as that generated by automobile ignition systems This function is not effective against non pulse type noise Push NB for 1 sec to enter the noise blanker...

Page 6: ...pears when the speech compressor ac tivates in SSB mode SCAN appears during scanning Flashes when scan is paused u SIGNAL SQL RF GAIN METER Functions as an S meter while receiving Functions as a Power ALC or SWR meter while transmitting p 16 i VFO MEMORY INDICATOR MEMO appears during regular operation This indicator appears only some versions VFO appears during VFO operation o CHANNEL NUMBER READO...

Page 7: ...ted the inter nal speaker does not function y ACCESSORY SOCKET ACC p 6 Enables connection to external equipment such as a TNC for data communications or a linear ampli fier etc u ELECTRONIC KEYER JACK KEY Accepts a paddle to activate the internal electronic keyer Selection between the internal electronic keyer and straight key operation can be made in initial set mode i ALC INPUT JACK ALC Connects...

Page 8: ... SEND Goes to ground when transmitting Input current Less than 20 mA When grounded transmits 4 BDT Data line 5 BAND Band voltage output 6 ALC ALC voltage output Control voltage 4 V to 0 V Input impedance More than 10 kΩ 7 NC 8 13 8 V 13 8 V output when power is ON Output current Max 1 A 9 TKEY Key line 10 FSKK RTTY key input Ground level 0 5 V to 0 8 V Input current Less than 10 mA 11 MOD Modulati...

Page 9: ...view CAUTION DO NOT short pin 2 to ground as this can damage the internal 8 V regulator q w y GND PTT ground t PTT r Main readout squelch switch q Microphone input w 8 V DC output e Frequency up down u GND Microphone ground i Main readout AF output varies with AF HM 36 SCHEMATIC DIAGRAM q w e r t y u i 4700 p 4700 p 10 µ 0 33 µ MICROPHONE MIC ELEMENT 2 k 470 DOWN UP PTT RECEIVE TRANSMIT MICROPHONE...

Page 10: ...revent electrical shock television interference TVI broadcast interference BCI and other prob lems ground the transceiver through the GROUND terminal on the rear panel For best results connect a heavy gauge wire or strap to a long earth sunk copper rod Make the distance be tween the GND terminal and ground as short as pos sible RWARNING NEVER connect the GND terminal to a gas or electric pipe sinc...

Page 11: ... wire or strap available and make the connection as short as possible Grounding prevents electrical shocks TVI and other problems ANTENNA Example 1 8 30 MHz bands DC POWER SUPPLY PS 85 CW KEY A straight key can be used when the internal electronic keyer is turned OFF in CW PADDL in initial set mode p 32 AH 710 Front panel Rear panel ...

Page 12: ...com power supply DC power cable polarity is correct Red positive terminal Black negative _ terminal CONNECTING A VEHICLE BATTERY 12 V battery Supplied DC power cable red _ black Crimp Solder Grommet NEVER connect to a 24 V battery NOTE Use terminals for the cable connections CONNECTING NON ICOM DC POWER SUPPLY DC power socket DC power supply AC outlet AC cable 20 A fuses Supplied DC power cable 13...

Page 13: ...Front panel ANTENNA Connects a linear amplifier etc REMOTE pgs 41 42 Used for computer control and transceive operation and cloning operation between transceivers SEND ALC Used for connecting a non Icom linear ampli fier EXTERNAL SPEAKER p 44 SP 21 etc ACC SOCKETS p 6 AT 120 AT 130 or AH 4 p 44 AH 2b or long wire with Rear panel ...

Page 14: ...3 INSTALLATION AND CONNECTIONS 12 External antenna tuners CONNECTING AN ANTENNA TUNER p 44 Coaxial cable from the tuner Long wire or optional AH 2b Ground IC 78 AT 120 AT 130 AH 4 Control cable Ground ...

Page 15: ...d channel This way is convenient when changing a small num ber of channels When a duplex channel different frequencies be tween transmit and receive is selected ap pears DUsing the keypad Enter the number of the desired channel number using the keypad 0 to 9 then push ENT This way is convenient for remembering the usage and stored channel number or when changing large a number of channels When a d...

Page 16: ...nient to wait for calls on multiple channels q Set RF SQL control at the center 12 o clock po sition opening squelch then rotate RF SQL control clockwise to the position where the noise disappears w Push DN or UP for 1 sec to start channel scan The SCAN indicator appears e When a signal is received channel scan pauses on that channel r Push DN or UP to cancel channel scan NOTE The scan resume cond...

Page 17: ...vance Microphone is connected AF control is set to minimum position RF SQL is set to center position squelch open RIT control set to center position w Selects the desired channel to be received with the channel selector DN UP or 10 key pad The S meter shows signal strength when signal is received e Adjust AF to the desired audio level when receiv ing a signal r Push MODE to select the desired oper...

Page 18: ...ch cases reduce the micro phone gain see above SWR Indicates the SWR over the transmission line Functions for transmit ï Output power and microphone gain Setting output power qPush SET for 1 sec to select quick set mode wPush UP DN to select RF POWER eRotate the main dial to select the desired output Output power is displayed in 101 steps L 1 99 and H but is continuously selectable Available power...

Page 19: ...n opportunity to input log entries into your computer etc while operating q Select VOX in quick set mode Push SET for 1 sec to select quick set mode Push UP DN to select VOX w Rotate the channel selector to turn VOX function ON e Select VOX GAIN in quick set mode Push UP DN to select VOX r While speaking into the microphone adjust VOX GAIN with the channel selector until the trans ceiver is transm...

Page 20: ...wer ON again MANUAL TUNING q Set the desired channel w Push TUNER to start tuning blinks and CW appears while tuning e lights constantly when tuning is completed except when AT 120 is connected the indicator goes out When the connected wire cannot be tuned the goes out the antenna tuner is bypassed and the an tenna wire is connected to the antenna connector on the transceiver directly r To bypass ...

Page 21: ... signals from distort ing when very strong signals are near the desired fre quency or when very strong electric fields such as from broadcasting stations are near your location Push ATT to turn the 20 dB attenuator function ON and OFF ATT appears when the attenuator is turned ON Appears when the attenuator is ON RIT off position ï Noise blanker The noise blanker reduces pulse type noise such as th...

Page 22: ...requency and cuts out higher or lower frequency components of the IF to reject interference The function shifts the IF frequency up to 1 2 KHz in SSB CW RTTY modes and up 250 Hz in CW narrow RTTY narrow modes The IF shift is not available in AM mode IF SHIFT OPERATION EXAMPLE Adjust the SHIFT control for a minimum interfer ence signal level When IF shift is used the audio tone may be changed Set t...

Page 23: ...signal 2nd IF signal DET CFWS450HT 6 kHz 3 Through 1 AM Narrow SSB CW RTTY Normal 3 AM Normal SSB CW RTTY Wide 2 OPTION Name Band width Mode FL 52A 500 Hz 6dB CW RTTY N FL 53A 250 Hz 6dB CW RTTY N FL 96 2 8 KHz 6dB SSB W FL 222 1 8 KHz 6dB SSB N FL 257 3 3 KHz 6dB SSB W Filter construction Rx Filter selection table no FL 52A FL 53A FL 96 FL 222 FL 257 WIDE 6 kHz 6 kHz 6 kHz 6 kHz 6 kHz 6 kHz SSB 2...

Page 24: ... selected the expanded filter selection can be used Wide narrow filter selection r Push UP Y several times until WIDE or NAR appears on the display t Push MODE several times to se lect the desired mode y Rotate the channel selector to se lect a filter u Repeat steps t and y to select IF filters for other modes if de sired The filter combinations are stored depending on operating modes i Push PWR f...

Page 25: ...e w Select CW or CW REV programmed channel e Set CW break in operation as semi break in full break in or OFF see p 30 Push SET for 1 sec to enter quick set mode Push UPY or ZDN several times until BK IN ap pears then rotate the channel selector to select the desired condition FL full break in SE semi break in oF no break in r Set the CW delay time when semi break in opera tion is selected see p 30...

Page 26: ... holding SET push PWR to enter initial set mode ePush UP DN one or more times until CW PADDL appears then rotate the main dial to se lect the paddle type When ud is selected the up down switches on the mi crophone can be use as a paddle When using up down switches as a paddle squeeze keying function is not available rPush UP DN one or more times until KEY RAT appears then rotate the main dial to s...

Page 27: ...SEND GND FSKK GND AF 2 conductor 1 8 plug ACC EXT SP 1 2 3 4 5 6 7 8 9 10 11 12 13 ï Connection for AFSK To a TU or TNC and personal computer Use either the ACC or microphone connector SQL 1 AF out AF in SEND GND 1 2 3 4 5 6 7 8 9 10 11 12 13 Rear panel view 1 Connect SQL line when required q Mic input MIC connector Front panel view 1 2 3 4 5 6 7 8 i AF output u Mic GND y PTT GND t PTT r SQL ACC c...

Page 28: ...are occasionally garbled when the receive signal is reversed between MARK and SPACE This reversal can be caused by incorrect TNC connections settings commands etc To receive a reversed RTTY signal correctly select RTTY R RTTY reverse mode Push MODE for 1 sec to select RTTY R RTTY re verse mode ï RTTY AFSK operation qConnect a terminal unit as on p 25 wSelect SSB LSB mode with MODE Generally LSB is...

Page 29: ...programmable mode 1st digit blinks r Push corresponding keys to enter desired charac ters see the following chart Push DN UP or rotate the channel selec tor to move the cursor to select the next charac ter or to change the digit t Push ENT for 1 sec to store the channel com ment ï Corresponding characters 1 space 4 G H I 7 P R S space w change digit KEY Assignable characters 2 A B C 5 J K L 8 T U ...

Page 30: ... quick set mode push SET momentarily DInitial set mode operation q Push PWR for 1 sec to turn power OFF w While pushing and holding SET push PWR to turn power ON Initial set mode is selected and one of its items appears e Push UPY or ZDN to select the desired item r Rotate the main dial to set the values or conditions for the selected item t Repeat e and r to set other items y To exit initial set ...

Page 31: ...X gain This item adjusts the VOX gain for the VOX voice activated transmit function The default is 50 Anti VOX level This item adjusts the ANTI VOX gain for the VOX voice activated transmit The default is 50 CW pitch This item adjusts CW pitch CW pitch is adjustable from 300 Hz to 900 Hz in 10 Hz steps The default is 60 600 Hz VOX delay This item adjusts VOX voice activated transmit delay time The...

Page 32: ... default is 20 wpm 40 44 47 50 52 54 56 57 59 cannot be selected Key ratio This item sets the CW key ratio or weight The ratio can be selected from 2 8 to 4 5 The default is 30 3 0 RTTY shift This item adjusts RTTY shift There are 4 selectable values 170 200 425 and 850 The default is 170 Hz Dimmer This item selects LCD back light brightness There are 3 selectable values Off Low and High The defau...

Page 33: ...e default is on Initial set mode items Meter peak hold Selects meter peak hold function on or off The default is on Scan resume Selects the scan resume function ON or OFF ON Resumes 10 sec after stopping on a signal or 2 sec after a signal disappears OFF Does not resume after stopping on a signal The default is on AM Noise blanker When this item is set to ON the noise blanker function is available...

Page 34: ...d controller or remote controller The default is At Auto CI V address To distinguish equipment each CI V transceiver has its own Icom standard ad dress in hexadecimal code The IC 78 s address is 62 When 2 or more IC 78s are connected to an optional CT 17 CI V LEVEL CON VERTER rotate the main dial to select a different address for each IC 78 in the range 01H to 7FH The default is 62 CI V Transceive...

Page 35: ...lter is installed this selection expands filter and filter se lection W N key combination in operating mode independently The default is oF off Filter select Wide When an optional IF filter is installed you can arrange the wide filter selection p 22 This item appears only when the Expand Filter as above is turned ON Initial set mode items continued Filter select Narrow When an optional IF filter i...

Page 36: ...as follows Tuning with the channel selector By rotating the channel selector operating fre quency changes in the desired tuning step set in the quick set mode p 30 This is the most convenient way when searching for signals around the pre programmed frequency Tuning with the keypad Enter the frequency as follows For duplex operation setting push TXF then set the transmit frequency after the receive...

Page 37: ...ramming q Store receive frequency as instructed above w Push TXF to indicate the transmit frequency The TX indicator blinks e Tune to the desired transmit frequency with the channel selector or keypad p 34 r Push ENT for 1 sec 3 beeps are emitted to store the transmit frequency into the selected channel The indicator appears FC ENT DCall channel programming The programmed frequencies both transmit...

Page 38: ...esting signal for a specified time period appears with the transmit indicator Push TONE again to cancel the distress alarm signal transmission Push CALL to return to previous condition TONE DChannel clearing If un necessary channels are available the stored fre quency can be cleared The cleared channels are skipped in the channel mode operation q Select desired channel in channel mode p 13 w Enter...

Page 39: ...e trans ceiver and 4 screws from the sides then lift up the top cover w Remove the 5 screws from the bottom of the trans ceiver then remove the bottom cover Optional bracket and carrying handle DMounting bracket An optional IC MB5 MOBILE MOUNTING BRACKET is available to install the radio under a table on a wall in a vehicle etc Select an area to mount the transceiver keeping in mind that the weigh...

Page 40: ... 201 J 401 P 2 Frequency check point Connect a frequency counter and adjust the frequency to 64 00000 MHz with C 16 C 16 MAIN unit PLL unit Optional IF filters Several IF filters are available for the IC 78 You can install 1 filter for 455 KHz IF Choose the appropriate filter for your operating needs pgs 21 22 DInstallation q Remove the bottom cover as shown on the p 48 w Remove 7 screws connectio...

Page 41: ...lockwise Antenna tuner is improperly matched to the operating frequency when manual tuning is selected CW or RTTY mode is selected for voice transmission Wrong type of mode emission is se lected Microphone is too close to your mouth The dial lock function is activated A quick set mode is selected Re connect the DC power cable correctly Check for the cause then replace the fuse with the spare one F...

Page 42: ...e the dam aged fuse with a new rated fuse CAUTION DISCONNECT the DC power cable from the transceiver when changing a fuse The IC 78 has 2 types of fuses installed for transceiver protection DC power cable fuses FGB 20 A Circuitry fuse FGB 4 A DC POWER CABLE FUSE REPLACEMENT 20 A fuse Resetting the CPU Returns programmed values in both quick and ini tial set mode to their defaults When first applyi...

Page 43: ...r s default address Controller s default address Command number see table at right Sub command number see table at right BCD code data for frequency or memory number entry End of message code fixed OK MESSAGE TO CONTROLLER FE FE E0 62 FB FD Preamble code fixed Controller s default address Transceiver s default address OK code fixed End of message code fixed NG MESSAGE TO CONTROLLER FE FE E0 62 FA ...

Page 44: ...e IC 78 s data programmed frequencies channel comment both quick and initial set mode conditions etc can be copied to the other IC 78 This function is useful when exactly the same setting of the IC 78s is required Cloning operation q Turn power OFF w Connects a mini plug cable between two IC 78 s master and sub REMOTE jack e While pushing TXF and FC turn the master IC 78 power ON r While pushing S...

Page 45: ...C connector 13 pin TRANSMITTER Modulation system SSB Balanced modulation AM Low level modulation Output power SSB CW RTTY 2 100 W AM 2 40 W Spurious emissions Less than 46 dB below peak output power Carrier suppression More than 40 dB Unwanted sideband More than 50 dB Microphone connector 8 pin connector 600 Ω RECEIVER Receiver system Double conversion superheterodyne Sensitivity 10 dB S N SSB CW ...

Page 46: ...on The PTT tuner start function provides simple operation Input power rating 120 W SP 20 EXTERNAL SPEAKER 4 audio filters headphone jack can connect to 2 transceivers Input impedance 8 Ω Max input power 5 W AH 2b ANTENNA ELEMENT A 2 5 m long an tenna element for mobile operation with the AH 4 Frequency coverage 3 5 28 MHz bands with the AH 4 PS 85 DC POWER SUPPLY Light weight switching regulator s...

Page 47: ...tor to 7 pin 8 pin ACC connector MB 23 CARRYING HANDLE Carrying handle convenient for portable operation IC MB5 MOBILE MOUNTING BRACKET Transceiver mounting bracket for mo bile operation HM 36 HAND MICROPHONE Hand microphone equipped with UP DOWN switches Same as supplied SM 8 DESKTOP MICROPHONE Including 2 connection cables for si multaneous connection of 2 trans ceivers Has UP DOWN switches SM 2...

Page 48: ...1 1 32 Kamiminami Hirano ku Osaka 547 0003 Japan A 5658H 1EX w Printed in Japan 2000 Icom Inc ...

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