Cobra 148GTL-DX User Manual Download

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Cobra 148GTL-DX

120-Channel

Solid State, Citizens Band

SS B/CW/AM/FM 2-Way

Mobile Radio

Cobra Communications Product Group

DYNASCAN CORPORATION

6460 W. Cortland Street

Chicago, Illinois 60635

Summary of Contents for 148GTL-DX

Page 1: ...Cobra 148GTL DX 120 Channel Solid State Citizens Band SSB CW AM FM 2 Way Mobile Radio Cobra Communications Product Group DYNASCAN CORPORATION 6460 W Cortland Street Chicago Illinois 60635 ...

Page 2: ...ction Manual for Cobra 148GTL DX 120 Channel Solid State Citizens Band SSB CW AM FM2 Way Mobile Radio о s Cobra Communications Product Group DYNASCAN CORPORATION 6460 W Cortland Street Chicago Illinois 60635 ...

Page 3: ...ols and Iridicators 12 A Control Functions 12 B Indicator Functions 14 Operating Procedure to Receive 14 Operating Procedure to Transmit 15 Receiving SSB signais Operating Procedure to CWMODE 17 Roger В еер 17 Alternate Microphones and Installation 18 Section V Maintenance and Adjustment 21 Section VI Appendix Ten Code 22 A Few Rules That Should Be Obeyed 23 How your CB Can Serve You 24 Use Channe...

Page 4: ...itizens Band lies between the shortwave broadcast and 10 meter amateur radio bands and was established by law in 1949 Two way communica tions service was opened in 1959 HAVE A GOOD DAY TODAY AND A BETTER DAY TOMORROW 3 ...

Page 5: ...and modes and in the CW mode providing complété coverage of ail 120 channels shown below CORRECTION CHANNEL LOW BAND MID BAND HI BAND 1 26 515 26 965 27 415 2 525 975 425 3 535 985 435 4 555 27 005 455 5 565 015 465 6 575 025 475 7 585 035 485 8 605 055 505 9 615 065 515 10 625 075 525 11 635 085 535 12 655 105 555 13 665 115 565 14 675 125 575 15 685 135 585 16 705 155 605 17 715 165 615 18 725 1...

Page 6: ...55 405 855 The COBRA 148GTL DX has a vastly superior receiver which includes an RF gain control and noise blanker circuitry effective in both AM FM and SSB CW modesr and an aut omatie n0ise4knker effective in the AM mode The receiver also features increased protection against cross modulation and strong adjacent channel signais To obtain maximum performance from your transceiver please read carefu...

Page 7: ...al 15 9V max 11 7V min positive or negative ground Transmit AM full mod 2 2A SSB 12 watts PEP output 2Â Receiver Squelched 0 3 A Maximum audio output 0 7A 2 3 8 H x 7 7 8 W x 9 l 4 D 5 lbs UHF S0239 Illuminated indicates relative output power received signal strength and SWR Size Weight Antenna Connector Meter 3 in l TRANSMITTER Power Output AM FM CW 5 watts SSB 12 watts PEP Modulation High and lo...

Page 8: ... for 10 dB S N N at greater than й watt of audio output AM 0 5 ßV for 10 dB S N N at greater than Й watt of audio output FM 1 0 jaV for 20 dB S N N at greater than й watt of audio output AM FM 6 dB 3 KHz 50 dB 9 KHz SSB CW 6 dB 2 1 KHz 60 dB 3 3 KHz More than 65 dB AM FM 10 695 MHz Ist IF 455 KHz 2nd IF SSB CW 10 695 MHz 60 dB AM FM 70 dB SSB CW 45 dB adjustable for optimum signal récep tion Less ...

Page 9: ...lling the holes make sure nothing will interfère with the installation of the mounting bolts 2 Connect the antenna cable plug to the standard réceptacle on the rear panel Most CB antennas are terminated with a type PL 259 plug and mate with the réceptacle 3 Connect the red DC power input wire with the fuse to 13 8V DC This wire éxtends from the rear panel In automobile installation 13 8V DC is usu...

Page 10: ...ansmission line to the radiating element In mobile installa tions cars trucks boats etc an antenna system that is non directional should be used A vertically polarized quarter wavelength whip antenna provides the most reliable operation and greatest range Shorter loaded type whip antennas are more attractive compact and adéquate for applications where the maximum possible distance is not required ...

Page 11: ... antenna you will notice the SWR reading will reach a low print and then start rising again This means that you have passed the opti mum point for Channel 21 Extend the antenna a short distance and again follow the procedure above _ __ _______ _________________ When the lowest point has been reached switch to Channel Low band and then to Channel 40 Hi band and compare SWR readings They sould he al...

Page 12: ...wer Converter that delivers the required power for the operation of the transceiver The CA 20 operates from any 120 volt 60 Hz power source Simply connect the red and black leads of the transceiver to the corresponding terminais of the CA 20 NOTE Do not attempt to operate this transceiver by connecting directly to 120 volts AC When the CA 20 Power Pak is used with the transceiver for base station ...

Page 13: ...the extemal speaker if used 3 SQUELCH outer dual concentric This control is used to eut off or elimi nate receiver background noise in the absence of an incoming signal For maximum receiver sensitivity it is desired that the control be Idjusted only to the point where the receiver background noise or ambient background noise is eliminated Tum fully counterclockwise then slowly clockwise until the ...

Page 14: ...ing the SWR CAL control to the CAL mark on the meter face ____ When in the SWR position the standing wave ratio is measured 7 MODE CW FM AM USB LSB SWITCH This switch is used to select CW FM AM LSB or USB mode of operation Unless the station with which communication is desired is equipped with SSB the AM or FM mode is normally used The mode selector switch changes the mode of operation of both tra...

Page 15: ...ch to SWR position for the SWR measurement 4 CHANNEL INDICATOR Numbered LED indicates the selected channel you wish to operate on LED indicates 9 when CH 9 is switched on 5 RECEIVER TRANSMIT INDICATOR The receiver transmit LED indicator is located next to the channel indicator When in receive the LED will be green When in transmit the LED will be red 6 PRESS TO TALK MICROPHONE The receiver and tra...

Page 16: ...FM mode by its characteristic Donald Duck sound and the inability of the AM or FM detector to produce an intel ligible output The USB and LSB modes will detect upper sideband and lower sideband respectively and standard AM signais SSB réception differs from Standard AM réception in that SSB receiver does not require a carrier or opposite sideband to produce an intelligible signal A single sideband...

Page 17: ... correct sideband is heard in either mode since both upper and lower sideband are received Once the desired SSB mode has been selected frequency adjustment may be necessary in order to make the incoming signal intelligible the VOICE LOCK control allows the operator to vary frequency above and below the exact center frequency of the received signal If the sound of the incoming signal is high or low...

Page 18: ...is set in RX condition automatically Be sure that the CODE transmitted from your station is heard as monitor sound from internai speaker see Fig 1 I 1 i 2 i 1 i 2 1 MARK TX SIGNAL ON TX NO SIGNAL RX CAUTION 1 MARK when CWKEY is closed 2 SPACE when CWKEY is opened 2 RECEIVE Adjust FINE CONTROL of VOICE LOCK for your desired sound when your transceiver is received MORSE CODE Signal ROGER ВЕЕР When t...

Page 19: ...schematic below 4WIREMIC CABLE Pin Number 1 2 3 4 Mic Cable Lead Audio Shield Audio Lead Transmit Control Receive Control If the microphone to be used is provided with pre cut leads they must be revised as follows 1 Cut leads so that they extend 7 16 beyond the plastic insulating jacket of the microphone cable 2 Ail leads shoudl be cut to the same length Strip the ends of each wire 1 8 and tin the...

Page 20: ...ing tool is available it should be used to hold the pin réceptacle body during the soldering operation so that both hands are free to perform the soldering If a vise or clamping tool is not available the pin ré ceptacle body сап be held in a stationary position by inserting it into the microphone jack of the front panel The numbers of the pins of the micro phone plug are shown in Fig 5 as viewed f...

Page 21: ...microphone plug are com plété push the knurled ring and the housing forward and screw the housing onto the threaded portion of the pin receptade body Note the location of the screw clearance hole in the plug housing with respect to the threaded hole in the pin réceptacle b ody When the housing is completely threaded into the pin réceptacle body a final fraction of a tiim either clockwise or counte...

Page 22: ...iability Should a failure occur however replace parts only with identical parts Do not substitute Refer to the sehcmatic dia gram and parts list N0TE If the performance described in the OPERATION and MAINTENANCE AND ADJUSTMENT sections is not obtained review the operating instructions to insure that proper procedures were followed If a prob lem still exists refer to WARRANTY SERVICE INSTRUCTIONS e...

Page 23: ...6 Correct time is 10 37 Wrecker needed at 10 10 Transmission completed 10 38 Ambulance needed at standing by 10 39 Your message delivered 10 11 Taking too rapidly 10 12 Visitors present 10 41 Please tum to channel 10 13 Advise Weather Road 10 42 Traffic accident at conditions 1043 Traffïc Tie up at 10 16 Make pick up at 1044 I hâve a message for you 10 17 Urgent business 1045 AU units within range...

Page 24: ... must identify your official licensed call sign at the beginning and end of every conversation 2 You are not allowed to carry on a conversation with another station for more than five minutes at a time without taking a one minute break to give others a chance to use the channel 3 You are not allowed to blast others off the air by over powering them with illegally amplified transmitter power or ill...

Page 25: ...ers HOW YOUR CB CAN SERVICE YOU Colonel Samuel S Smith of the Missouri Highway Patrol called the numbers of drunken drivers wrong way drivers and speeders reported by CBers as amaz ing Не said that even the Smokey Bear warnings don t shake their beliefs that the potential benefits of CB radio to law enforcement are so great that they far outweight the disadvantages In regards to CB radar warnings ...

Page 26: ...out of gas on Interstate 95 No I am out of gas in my driveway Yes There is a four car collision at Exit 10 on the Beltway send police and ambulance No fTraffic is moving smoo thly on the BeItway Yes Base to Unit 1 the Weather Bureau has just issued a thunderstorm warning Bring the sailboat into port No Attention all motorists The Weather Bureau advises that the snów tomorrow will accumulate 4 to 6...

Page 27: ...nclose a letter describing the problem and include your name and address DeUver to or ship PREPAID UPS preferred to the nearest Cobra authorized service agency see list enclosed with unit If your list of authorized Cobra service agencies has been misplaced contact your local dealer for the name of your nearest service agency or Write to WARRANTY SERVICE INSTRUCTIONS Service Department Cohra Produc...

Page 28: ...your produet instruction booklet certain COBRA models are suitable for dashboard installation without modification of the dash In other cases Professional installation is recommended In either event DYNASCAN is not responsibleJojudanaages to the produet or the automobile resulting from improper installation DYNASCAN shall not be liable for any consequential damages including without limitation dam...

Page 29: ...obr Cobra Communications Product Group DYNASCAN CORPORATION 6460 W Cortland Street Chicago Illinois 60635 480 234 9 001 Printed in Taiw an ...

Page 30: ...SERVICE MANUAL 148 GTLDX EARLY LATE VERSIONS COBRA COMMUNICATIONS PRODUCTION GROUP DYNASCAN CORPORATION 6460 W CORTLAND ST CHICAGO ILLINOIS 60635 ...

Page 31: ...in PCB Bottcm View Copper Pattem SWR PCB CH SW PCB LED PCB Parts Layout Sub Assy PCB s Top View Semi Conductor Pin Configuration Internal Diagrams ICs Voltage Charts Late Version Block Diagram Schematic Diagram Wiring Diagram Alignment Procedure Copper Pattem Main PCB Parts Layout Main PCB Top View Added Parts Main PCB Parts Layout Sub Assy PCBs Copper Pattern Sub Assy PCBs Parts Layout Mic Jack S...

Page 32: ...со SO AOJ VR2 BLOCK DI AGRAM ...

Page 33: ...SCHEMATIC DIAGRAM ...

Page 34: ...WIRING DIAGRAM OFF LOW OFF CAL P C 8 8 I P C 8 8 0 Y Y 027 Wl YEL 1 5 4 0 3 ____ J 503 ANT J 502 6 7 ...

Page 35: ...or 5 4V reading on DC Voltmeter 3 Same as Step 1 L16 Connect Oscilloscope to TP3 lead of R101 Adjust for maximum indication on Oscilloscope 4 Same as Step 1 L31 Connect Frequency Counter to TP3 lead of R101 Adjust for 16 490MHz or 20Hz 5 Same as Step 1 CH 40 Mode USB L32 Adjust for 16 4925MHz or 20Hz 6 Same as Step 1 CH 40 Mode LSB L33 Adjust for 16 4875MHz or 20Hz 7 Same as Step 6 CH 40 TX Mode V...

Page 36: ...ep 11 CH 40 Mode USB L41 Adjust for 16 9425MHz or 20Hz 13 Same as Step 12 CH 40 Mode LSB L42 Adjust for 16 9375MHz or 20Hz 14 Same as Step 1 Œ 40 TX Mode L47 Connect Frequency Counter to TP4 R114 Adjust for 10 695MHz or 5Hz 15 Same as Step 1 CH 40 Mode USB L48 Connect Frequency Counter to TP5 lead of R39 Adjust for 10 6925MHz 5Hz 0Hz 16 Same as Step 15 CH 40 Mode LSB L49 Adjust for 10 6975MHz 0Hz ...

Page 37: ... T u m the Core of L4 to the bottom 3 Same as Step 1 L3 L5 L6 L7 L8 L17 L18 and L4 Adjust for maximum reading and readjust L4 for maximum reading 4 Same as Step 1 except NB ANL ON LI and L2 Set the SG on Mid Œ18 27 175MHz unit is CH19 with no modulation Connect Osci lloscope to lead of D2 and adjust coils for maximum reading Then set the level of SG to 5uV then readjust this step D2 is TP1 5 Same ...

Page 38: ...C 2 8 Same as Step 7 L U Set the SG to ImV with 1 5kHz déviation of 1kHz Adjust Lll for maximum sign wave output on Oscilloscope ALIQMENT OF TRANSMITTER PORTION 1 Test Equipment Required a DC Arrmeter b Power meter c RF VTVM d Oscilloscope e Deviation Meter f 50 ohm Dummy Load g Frequency counter 2 Alignment Precedure STEP PRESET TO ADJUSTMENT REMARKS 1 CH 19 TX Mode Mode USB Mic Gain Min VR10 Rem...

Page 39: ... Mic Input 90 L54 Adjust for maximum reading on RF VTVM Final Output Adj 7 Same as Step 3 VR7 Adjust ALC for 24 5V reading on RF VTVM 12w 50ohm Single tone 8 Same as Step 1 VR4 Adjust for minimum reading on Oscilloscope for both USB abd LSB minimum carrier Adj 9 Same as Step 1 except Mode AM VR11 Adjust for 5 0W reading on RF Pcwer Meter AM carrier output adj 10 Mic Input 30mV lKHz VR8 Set the met...

Page 40: ... FM Band Low 40 Mic Input 30mV 1kHz VR3 Adjust for 4 5kHz déviation FM Deviation Adj 13 Same as Step 12 except Mode CW VR12 Adjust 0 2V reading on AF VTVM when CW key is keyed Side tone adj 14 Same as Step 1 except CH 9 CW CH 9 Check that the output frequency is 27 065 MHz on Frequency Counter ...

Page 41: ...Parts Layout Top View Î37 2SB525C 1 4 1 5 ...

Page 42: ...PARTS LAYOUT Top View ...

Page 43: ...ADDED PARTS MAIN PCB Bottom View PC 879AB ...

Page 44: ...COPPER PATTERN SWR PCB CH SW PCB LED PCB CD ...

Page 45: ...PARTS LAYOUT SUB ASSY PCB s Top View PC 8 8 0 AA CH SW PCB PC 958АД ж CD CN CO CO I CM Ш P C 9 S A A SWR P C B 20 ...

Page 46: ...SC945A Q 2SC1674L 2SC1675L 2SC1730L 2SA733P ANODE CD CATHODE 1N60 AM 1SS97 1S2075K MC 301 1S2688EB MV 201 RD75EB2 KB262 MARKING 2SC1312F 2SC2086D 2SB525C ANODE CATHODE TLRG 101 1N4003 MARKING SIDE В С Е a cd а L U 2SC1969B 2SC2166C 2SA4730 2SA1012O iGREEN UR 202 MV1Y MARKING CATHODE ANODE 8 ...

Page 47: ...INTERNAL DIAGRAM IC s SCHEMATIC DIAGRAM CONNECTION INFORMATION OB and DC Dual In Lin Р к к а д м Top View Order Part No LM124D LM224D LM324D LM2902D LM224N LM324N LM2902N ...

Page 48: ...го w INTERNAL DIAGRAM IC s MB87I9 ...

Page 49: ...INTERNAL DIAGRAM IC s го А ...

Page 50: ...INTERNAL DIAGRAM IC s S 0 4 2 P 25 ...

Page 51: ...0 0 0 A M 0 0 0 U S B 0 7 0 0 L S B 0 0 0 Mode Base C o lle c te r E initter TR 9 RX CW 1 3 5 0 0 7 FM 1 3 5 0 0 7 A M 1 3 5 0 0 7 USB 1 3 5 0 0 7 LSB 1 3 5 0 0 7 TX CK 1 3 5 0 0 7 FM 1 3 5 0 0 7 A M 1 3 5 0 0 7 USB 1 3 5 0 0 7 ISB 1 3 5 0 0 7 TR 10 RX CW 0 0 0 FM 0 0 0 A M 0 0 0 USB 0 0 0 ISB 0 0 0 SQ CW 0 7 0 0 TX CW 0 0 0 FM 0 0 0 AM 0 0 0 USB 0 0 0 ISB 0 0 0 TR 11 PX CW 2 1 7 8 1 4 FM 2 1 7 8 ...

Page 52: ... USB 2 1 7 3 1 5 D USB 2 5 7 7 1 9 Ж 3 6 7 1 3 0 LSB 2 1 7 3 1 5 LSB 2 5 7 7 1 9 AM 3 6 7 1 3 0 CW Ż 1 7 4 1 5 CW 2 5 7 8 1 9 USB 3 6 7 1 3 0 H 2 1 7 4 1 5 H FM 2 4 7 5 1 8 LSB 3 6 7 1 3 0 ï AM 2 1 7 4 1 5 1 AM 2 4 7 5 1 8 TX CW 0 1 0 1 0 USB 2 1 7 4 1 5 USB 2 5 7 8 1 9 Ж 0 1 0 1 0 LSB 2 1 7 4 1 5 LSB 2 5 7 8 1 9 AM 0 1 0 1 0 USB 0 1 0 1 0 LSB 0 1 0 1 0 TX CW 2 1 7 3 1 5 TR 19 RX CW 0 0 0 L FM 2 1...

Page 53: ...7 6 7 4 USB 8 3 0 8 3 USB 4 2 7 7 7 5 ISB 8 3 0 8 3 I LSB 4 2 7 7 7 5 Mode B ase CoH e c t o r E m itte r t Mode B ase E m itte r TR 36 RX CW 5 5 7 8 7 5 TR 40 RX CW 0 9 3 2 0 3 та 5 5 7 8 та 0 9 3 2 0 3 AM 5 5 7 8 7 5 AM 0 9 3 2 0 3 USB 5 5 7 8 USB 0 9 3 2 0 3 LSB 5 5 7 8 ISB 0 9 3 2 0 3 TX CW 1 4 0 8 0 7 TX от 0 9 3 2 0 3 та 1 4 0 8 0 7 та 0 9 3 2 0 3 AM 1 4 0 8 0 7 AM 0 9 3 2 0 3 USB 1 4 0 8 US...

Page 54: ...M 1 1 3 11 3 1 1 8 FM 0 0 Л 0 AM 1 1 3 11 3 1 1 8 AM 0 0 7 0 USB 1 3 7 1 3 7 1 3 0 USB 0 0 7 0 LSB 1 3 7 1 3 7 1 3 0 LSB 0 0 7 0 TR 49 RX cw 1 3 3 1 3 2 1 3 8 TR 53 RX cw 0 0 0 FM 1 3 3 1 3 2 1 3 8 FM 0 0 0 AM 1 3 3 13 2 1 3 8 AM 0 0 0 USB 1 3 1 1 3 8 1 3 8 USB 0 0 0 LSB 1 3 1 1 3 8 1 3 8 LSB 0 0 0 TX CW 1 3 1 12 4 1 3 7 TX CW 0 0 0 FM 1 1 8 11 3 1 3 2 FM 0 0 0 AM 1 1 8 11 3 1 3 2 AM 0 0 0 USB 1 3...

Page 55: ...3 RX CW 3 4 4 5 5 5 3 6 3 6 8 2 4 5 4 9 8 2 8 2 0 0 8 2 0 5 8 2 3 8 0 o o n t H FM 3 4 4 5 5 5 3 6 3 6 8 2 4 5 4 9 8 2 8 2 0 0 8 2 0 5 8 2 3 8 0 I AM 3 4 4 5 5 5 3 6 3 6 8 2 4 5 4 9 8 2 8 2 0 0 8 2 0 5 8 2 3 8 0 USB 3 4 4 5 5 5 3 6 3 6 8 2 4 5 4 9 8 2 8 2 0 0 8 2 0 5 8 2 3 8 0 LSB 3 4 4 5 5 5 3 6 3 6 8 2 4 5 4 9 8 2 8 2 0 0 8 Ï 0 5 6 2 3 8 Q Т Я TS l G 4 6 6 1 T T Tr 8 2 4 5 4 9 8 2 8 2 0 0 8 2 0 ...

Page 56: ...0 0 0 4 1 8 1 8 0 0 0 10 9 USB 13 7 6 6 0 0 3 1 8 1 8 0 0 0 11 4 LSB 13 7 6 6 0 0 3 1 8 1 8 0 0 0 11 4 IC 6 RX CW 0 0 0 0 0 0 0 0 0 0 0 5 0 0 5 0 FM 0 0 0 0 0 0 0 0 0 0 0 5 0 0 5 0 AM 0 0 0 0 0 0 0 0 0 0 0 5 0 0 5 0 USB 0 0 0 0 0 0 0 0 0 0 0 5 0 0 5 0 LSB 0 0 0 0 0 0 0 0 0 0 0 5 0 0 5 0 TX CW 0 7 8 7 8 0 7 9 0 2 8 2 8 0 1 3 1 3 1 3 1 3 0 FM 0 7 8 7 8 0 7 8 0 2 7 2 7 0 1 3 1 3 1 3 1 3 0 AM 0 7 8 7 ...

Page 57: ...in PCB Bottcm View Copper Pattem SWR PCB CH SW PCB LED PCB Parts Layout Sub Assy PCB s Top View Semi Conductor Pin Configuration Internal Diagrams ICs Voltage Charts Late Version Block Diagram Schematic Diagram Wiring Diagram Alignment Procedure Copper Pattem Main PCB Parts Layout Main PCB Top View Added Parts Main PCB Parts Layout Sub Assy PCBs Copper Pattern Sub Assy PCBs Parts Layout Mic Jack S...

Page 58: ...со го BLOCK DI AGRAM ...

Page 59: ...PB OIO SCHEMATIC DIAGRAM ...

Page 60: ...WiRING DIAGRAM 3 5 3 6 P C 881 P C 8 8 0 ...

Page 61: ...Volts re ading 3 Saine as Step 1 Connect Oscilloscope to TP 3 Lead of R84 L19 Adjust for Max reading 4 Same as Step 1 Same as Step 3 L21 Adjust for 16 490MHz 5 Same as Step 1 except Mode SW USB Same as Step 3 L22 Adjust for 16 4925MHz 6 Same as Step 1 except Mode SW USB Same as Step 3 L23 Adjust for 16 4875MHz 7 Same as Step 6 except Band SW Mid Same as Step 3 VR6 Adjust for 16 4875MHz 8 Same as S...

Page 62: ...9 OFF Coarse Center VRll Remove PC 834 PCB and connect DC Am meter to TP9 and TP8 Adjust for 50mA reading 2 Same as Step 1 VR10 Connect DC Ammeter to TP9 and TP7 and adjust for 50mA reading 3 Same as Step 1 except Mic input 30mV VR12 L53 Restore PC 834 T u m VR12 to Mac CW and tu m the core of L53 to the obttcm 4 Same as Step 3 L52 54 55 Adjust for Max reading on RF VTVM 5 Same as Step 3 L53 Set t...

Page 63: ...ter 10 Same as Step 9 VR 8 Set the meter SW to S RF position Adjust the VR 8 so that the radio s meter reads 5W Between Green zone and Red zone 11 Same as Step 9 except Mic input 30mV VR14 Adjust 90 modulation on Oscilloscope 12 Same as Step 1 except Mode SW Ш Band 40 Mic input 30mV VR 5 Adjust for 5kHz déviation 13 Same as Step 12 except Mode CW VR15 Adjust 0 2V reading on AF VTVM when CW key is ...

Page 64: ... OFF Coarse Center VRll Rénové PC 834 PCB and connect DC Am meter to TP9 and TP8 Adjust for 50mA reading 2 Same as Step 1 VR10 Connect DC Ammeter to TP9 and TP7 and adjust for 50mA reading 3 Same as Step 1 except Mic input 30mV VR12 L53 Restore PC 834 T u m VR12 to Mac CW and t um the core of L53 to the obttcm 4 Same as Step 3 L52 54 55 Adjust for Max reading on RF VTVM 5 Same as Step 3 L53 Set th...

Page 65: ...ignal will appear on Oscilloscope Repeat it for SSB CW Mode with VR3 7 Same as Step 1 VR1 for AM FM VR2 for SSB CW Set the SG to 40CH 27 405MHz with No modulation Level of SG is lOOuV Then adjust VRl for S 9 reading on radio s meter for AM mode Repeat it for SSB CW mode with VR2 8 Same as Step 1 Mode Ш L6 Set the SG tl lrnv with 1 5kHz déviation of 1kHz Adjust Lb for Max signwave output on Oscillo...

Page 66: ...COPPER PATTERN MAIN PCB ...

Page 67: ...EE CA A Ci TA N СE vA L и E S ARr j n l e s s o t h e r w i s e n o t e s A ll CAPACi TORS TEMPERA ARE SL LES S TP AN 10 0 1000 PE aNLE SS O p Fr w C27I 0047 ZF K i S û о й c 7 Q O l MCI4008BCP T b ü JP65 l lO 045 iS J VJ R 59 47K T 2 r s i s 4 47K е й t i 3 S C O O c i Ct î f i IA O 05 4 so o s k 0 5 5 S2075K ...

Page 68: ...P B O I O ADDED PARTS MAIN PCB H fs il 8 46 ...

Page 69: ... рь nI PARTS LAYOUT SUB ASSY PCB s T3 r I tp m S 4 Ï X t О Г О О о го го о 3 f 3 3 о о о о го R40Ö R 414 680 G Е2А 3724 ...

Page 70: ...COPPER PATTERN SUB ASSY PCB s ...

Page 71: ...PARTS LAYOUT MIC JACK 49 ...

Page 72: ...ION 2SA733 P 2SC945A Q 2SC1674 L 2SC1675 L 2SC1730 L 2SA473 0 2SA1012 0 2SC2166 C 2SC2312 C 2SB525 C 2SC2086 D CAT HODE MARK ANODE CATHODE 1N60 AM MC 301 1N4003 MV 201 1S2339G RD5 1EB2 RD7 5EB2 KB262 1S2075K N 4 Y TLRG 101 UR202 50 ...

Page 73: ...INTERNAL DIAGRAM IC s DIFFERENTIAL PEAK DETECTOR Ł BIAS CIRCUIT T T ul И Г Ш LU Ы INPUT BYPASS Vcc GND DET 1NPUT DET INPUT OUTPUT UPC1028H 51 ...

Page 74: ...INTERNAL DIAGRAM IC s MC14008B 1 4 Cou l 13 S 4 13 S 3 11 S2 10 S 1 16 15 14 13 12 11 10 9 52 ...

Page 75: ...сл С О INTERNAL DIAGRAM IC s OSC out Г 2 out FS PO PI P2 P3 PA P5 P6 P7 P8 MC145106 ...

Page 76: ...INTERNAL DIAGRAM IC s 14 0UT4 13 I N 4 12 lN 4 11 VEE 10 IN 3 9 I N 3 8 0UT3 TA75902P 54 ...

Page 77: ...INTERNAL DIAGRAM IC s S 042P 55 ...

Page 78: ...0 0 TR 12 RX CW 0 7 0 0 FM 0 0 0 AM 0 0 0 USB 0 7 0 0 LSB 0 7 0 0 TX CW 0 7 0 0 FM 0 0 0 AM 0 0 0 USB 0 7 0 0 LSB 0 7 0 0 Mode B ase CoH e c to r E in itte r TR 5 RX c w 0 7 7 0 FM 0 7 7 0 AM 0 7 7 0 USB 0 7 7 0 LSB 0 7 7 n NB ON 0 7 7 0 TX CW 0 0 0 FM 0 0 0 AM 0 0 0 USB 0 0 0 LSB 0 0 0 TR 6 RX CW 7 7 0 8 3 FM 7 7 0 8 3 AM 7 7 0 8 3 USB 7 7 0 8 3 LSB 7 7 0 8 3 NB ON 7 7 0 8 3 TX CW 0 0 0 FM 0 0 0 ...

Page 79: ...5 TR 20 RX О Т 0 7 3 6 0 EM 0 4 1 9 0 AM 0 4 1 9 0 USB 0 7 3 6 0 LSB 0 7 3 6 0 TX CW 0 0 0 FM 0 0 0 AM 0 0 0 USB 0 0 0 LSB 0 0 0 Mode B ase C o lle c to r E in itte r TR 25 RX cw 1 4 4 8 0 9 EM 1 4 4 8 0 9 AM 1 4 4 8 0 9 USB 1 4 4 8 0 9 LSB 1 4 4 8 0 9 TX CW 1 4 4 8 0 9 FM 1 4 4 8 0 9 AM 1 4 4 8 0 9 USB 1 4 4 8 0 9 LSB 1 4 4 8 0 9 TR 26 RX CW 2 1 7 3 1 4 FM 2 1 7 3 1 4 AM 2 1 7 3 1 4 USB 2 1 7 3 1...

Page 80: ...2 0 6 RX CW 1 4 8 1 0 8 EM 7 8 0 6 8 3 FM 7 6 8 2 8 4 Ж 1 2 3 2 0 6 Ж 1 4 7 4 0 8 AM 7 8 0 6 8 3 AM 7 6 8 2 8 4 AM 1 2 3 2 0 6 AM 1 4 7 4 0 8 USB 7 8 0 6 8 3 USB 7 6 8 2 8 4 USB 1 2 3 2 0 6 USB 1 4 8 1 0 8 LSB 7 8 0 6 8 3 LSB 7 6 8 2 8 4 LSB 1 2 3 2 0 6 LSB 1 4 8 1 0 8 TR 35 RX cw 8 2 8 3 7 7 TR 39 RX CW 0 6 9 0 0 TR 43 RX CW TR 47 RX CW 0 0 0 FM 0 0 7 7 FM 0 0 0 FM ж 0 0 0 AM 0 0 7 7 AM 0 0 0 AM ...

Page 81: ...4 RX CW 0 0 0 FM 0 7 0 0 AM 0 0 0 USB 0 0 0 LSB 0 0 0 TX CW 0 0 0 FM 0 7 0 0 AM 0 0 0 USB 0 0 0 LSB 0 0 0 TR 55 RX CW 0 7 0 0 FM 0 7 0 0 AM 0 7 0 0 USB 0 7 0 0 LSB 0 7 0 0 TX CW 0 7 0 0 FM 0 7 0 0 AM 0 Л 0 0 USB 0 7 0 0 LSB 0 7 0 0 Mode 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 IC 1 RX CW 8 4 0 1 0 1 0 3 0 1 9 1 5 0 0 3 0 3 0 6 FM _ _ _ 8 4 0 0 0 0 1 9 1 5 0 0 3 0 3 0 6 AM _ _ 8 4 0 0 0 0 1 9 1...

Page 82: ...c o n t L FM 8 3 4 3 4 3 4 3 3 2 8 3 0 0 0 0 0 8 3 0 8 3 8 3 0 0 AM 8 3 4 3 4 3 4 3 3 2 8 3 0 0 0 0 0 8 3 0 8 3 8 3 0 W USB 8 3 4 3 4 3 4 3 3 2 8 3 0 0 0 0 0 8 3 0 8 3 8 3 0 LSB 8 3 4 3 4 3 4 3 3 2 8 3 0 0 0 0 0 8 3 0 8 3 8 3 0 CW Ô 3 4 3 4 3 4 3 4 7 8 2 0 0 8 3 0 ä J 0 8 3 0 0 8 3 M FM 8 3 4 3 4 3 4 3 4 7 8 2 0 0 8 3 0 8 3 0 8 3 0 0 8 3 1 AM 8 3 4 3 4 3 4 3 4 7 8 2 0 0 8 3 0 8 3 0 8 3 0 0 8 3 D U...

Page 83: ...8 3 LSB 0 0 0 0 8 3 7 9 0 0 8 3 0 0 8 3 8 3 7 9 8 3 Mode 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 IC 7 TX CW 0 7 9 0 0 8 3 0 0 0 0 0 8 3 8 3 0 _ 0 8 3 oon t L FM 0 7 9 0 0 8 3 0 0 0 0 0 0 3 8 3 0 0 8 3 0 AM 0 7 9 0 0 8 3 0 0 0 0 0 8 3 8 3 0 0 8 3 w USB 0 7 9 0 0 8 3 0 0 0 0 0 0 3 8 3 0 0 8 3 LSB 0 7 9 0 0 8 3 0 0 0 0 0 8 3 8 3 0 0 8 3 CW 0 7 9 0 7 9 Ö 3 7 9 0 0 0 O 0 0 8 3 0 6 3 M FM 0 7 9 0 7...

Page 84: ... min positive or negative ground Transmit AM full mod 2 2A SSB 12 watts PEP output 2A Receiver Squelched 0 3 A Maximum audio output 0 7 A 2 3 8 H x 7 7 8 W x 9 1 4 D 5 lbs UHF S0239 Illuminated indicates relative output power received signal strenght and SWR AM FM CW 5 watts SSB 12 watts PEP High and lcw level Class B Anplitude Modu lation AM Variable capacitance Frequency Modulation FM SSB 3rd or...

Page 85: ...ohms 300 to 2800 Hz 8 ohms round 8 ohms disables internai speaker when con nected FREQUENCY CHANNEL ùOW BAND MID BAND HI В А Ш CHANNEL LCW BAND MID BAND HI BAND 1 26 515 26 965 27 415 2 525 975 425 3 535 985 435 4 555 27 005 455 5 565 015 465 6 575 025 475 7 585 035 485 8 605 055 505 9 615 065 515 10 625 075 525 11 635 085 535 12 655 105 555 13 665 115 565 14 675 125 575 51 685 135 585 16 705 155 ...

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