E.F. Johnson Company 761X Page 64 Service Manual Download

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ADJUSTMENT PROCEDURE

6-9

November 1998

Part No. 001-7600-001

Figure 6-6 UHF Adjustment Points

6.7.4 DTCS WAVEFORM ADJUST

1. Select the channel on the low end of the pro-

grammed for DTCS code 007N (Test Ch. 5).

2. On the computer screen, scroll to “DTCS N” if set-

ting a narrow band channel or “DTCS W” if setting
a wideband channel.

3. Key the transmitter and view the demodulated sig-

nal on the CRT of a communications monitor.

4. Press the adjust keys on the computer so that the

waveform appears as follows:

5. If the transceiver operates on both narrow and wide

band channels, select Test Ch. 7 and also set the
waveform on that channel (see note in Table 6-2).

L23

PLL lock voltage
adjustment

CP1
PLL lock voltage
check point

L26

PLL lock voltage
adjustment

Set For

Flat

Waveform

UHF ADJUSTMENTS (CONT’D)

Summary of Contents for 761X

Page 1: ...First Printing November 1998 761x VHF 764x UHF Conventional Mobile VHF 146 174 MHz 45 Watts Part No 242 7610 0xx UHF 400 430 450 470 470 490 490 512 MHz 35 Watts Part No 242 7640 0xx Service Manual ...

Page 2: ...variety of markets including government public safety and commercial users Transcrypt s information security devices utilize sophisticated scrambling and encryption techniques to protect sensitive voice and data transmissions Viking Head EFJohnson logo and Call Guard are registered trademarks of Transcrypt International Incorporated Smartrunk II is a trademark of Smartrunk Systems Inc All other co...

Page 3: ... 2 Back Panel 3 2 3 3 BASIC OPERATION 3 2 Turning Power On and Off 3 2 Entering a Password 3 3 Volume Level Adjustment 3 3 Power On Menu 3 3 Channel Selection 3 3 Adjusting Squelch Level 3 3 Bank Select 3 4 Automatic Scan Enable 3 4 Backlight On Off 3 4 Beep On Off 3 4 3 4 RECEIVING AND PLACING CALLS 3 4 Introduction 3 4 Receiving a Call 3 4 Placing a Call 3 4 Monitoring Before Transmitting 3 4 Ti...

Page 4: ... 9 Microphone Amplifier Circuit 5 9 Modulation Circuit 5 9 Transmit Driver Circuit 5 9 Power Amplifier Module 5 9 APC Circuit 5 10 5 7 UHF PLL CIRCUIT 5 10 PLL Circuit 5 10 VCO Circuit 5 11 UHF Power Supply 5 11 UHF CPU IC1 Port Allocation 5 11 UHF I O Expander IC12 Main Unit 5 12 UHF Port Expander IC13 Main Unit 5 12 6 ADJUSTMENT PROCEDURE 6 1 GENERAL 6 1 Suggested Test Equipment 6 1 Test Channel...

Page 5: ... Description 4 10 4 5 Scan Function Screen Description 4 10 4 6 2 Tone Code Channel Screen Description 4 11 4 7 Common Screen Description 4 13 4 8 Expert Screen Description 4 14 6 1 VHF Test Frequencies 6 3 6 2 UHF Test Frequencies 6 3 LIST OF FIGURES 2 1 Installation Components 2 1 2 2 Mounting Bracket Installation 2 2 2 3 Accessory Cable Installation 2 3 2 4 Cover and Front Panel Removal 2 4 2 5...

Page 6: ...le from your product supplier or from the War ranty Department EFJohnson 299 Johnson Avenue P O Box 1249 Waseca MN 56093 0514 This infor mation may also be requested from the Warranty Department by phone as described in Section 1 7 The Warranty Department may also be contacted for War ranty Service Reports claim forms or any other ques tions concerning warranties or warranty service 1 4 PART NUMBE...

Page 7: ...pment because a ser vice representative may be able to suggest a solution to the problem so that return of the equipment would not be necessary Be sure to fill out a Factory Repair Request Form 271 for each unit to be repaired whether it is in or out of warranty These forms are available free of charge by calling Customer Service see Section 1 7 or by requesting them when you send a unit in for re...

Page 8: ...rtment To order parts by phone dial the toll free number as described in Section 1 7 When ordering please supply the part number and quantity of each part ordered EFJohnson dealers also need to give their account number If there is uncertainty about the part number include the desig nator C512 for example and the model number of the equipment the part is from You may also send your order by mail o...

Page 9: ...GENERAL INFORMATION 1 4 November 1998 Part No 001 7600 001 This page intentionally left blank ...

Page 10: ...rols 1 6 H x 5 5 W x 6 7 D 4 1 cm x 13 9 cm x 17 0 cm Weight 2 lb 11 oz 1 22 kg Supply Voltage 13 6 volts DC nominal 12 volt negative ground vehicle electrical system Current Drain maximum Standby 200 mA standby Receive rated audio out 700 mA Medium Tx Power 6 0 A VHF 7 0 A UHF High Tx Power 15 A max 10 A typ VHF 11 A max 8 A typ UHF FCC Compliance Parts 15 and 90 RECEIVER Sensitivity 12 dB SINAD ...

Page 11: ...GENERAL INFORMATION 1 6 November 1998 Part No 001 7600 001 NOTES ...

Page 12: ...er frequency deviation and power output 2 1 3 TRANSCEIVER PROGRAMMING The transceiver needs to be programmed before it is placed in service Programming instructions are located in Section 4 Transceivers normally contain factory test channels and other test parameters when they are shipped The included labels should be attached to the option keys to indicate the function 2 1 4 POWER SOURCE This tra...

Page 13: ...ts that could be damaged when the mounting screws are installed Then install the bracket and trans ceiver as shown in Figure 2 2 Both standard and self tapping screws are included for installing the bracket 2 2 3 INSTALLING MICROPHONE HANGER Install the included microphone hanger in a con venient location For proper operation of functions such as monitoring and scanning the hanger may need to be c...

Page 14: ...speaker can be plugged into the external speaker jack on the back of the transceiver This speaker should have an impedance of 4 8 ohms and a power handling capability of at least 3 5 watts The internal speaker is automatically disabled when a speaker is plugged into this jack The external speaker jack is a standard 1 8 inch two conductor phone jack 2 5 ACCESSORY CABLE INSTALLATION Optional Accesso...

Page 15: ...own in Figure 2 4 2 Remove the front panel by removing two screws B Figure 2 4 Cover and Front Panel Removal Removing PC Board 3 Remove ten screws C and two clips D as shown in Figure 2 5 4 Remove shield E 5 Unsolder the antenna connector at three points F 6 Lift the front of the PC board assembly as shown in Figure 2 6 and pull it out Figure 2 5 PC Board Screws Figure 2 6 Removing PC Board ...

Page 16: ... the decoder can be re activated when the call is complete see Table 4 2 2 7 3 5 TONE PROGRAMMING Program the transceiver for operation with a five tone module as described in Section 4 Screens that need to be programmed with five tone decoder infor mation are as follows Refer to on line help for infor mation on parameters in these screens press F1 with parameter selected Model Menu PMR must be se...

Page 17: ...iometer R18 DEV on the module for the following deviation 25 kHz Channel Spacing 3 5 kHz 20 kHz Channel Spacing 2 8 kHz 12 5 kHz Channel Spacing 1 7 kHz 4 Check channels on each end of the operating band to make sure deviation is within the following limits If not repeat preceding adjustment 25 kHz Channel Spacing 3 0 to 5 0 kHz 20 kHz Channel Spacing 2 4 to 4 0 kHz 12 5 kHz Channel Spacing 1 5 to...

Page 18: ...and priority scan to ensure that calls are not missed Up to five different user programmable scan lists selectable Bank select available up to two banks with sixteen channels each User selectable power output available DTMF microphone optional 2 tone 5 tone signaling optional NOTE Some of the preceding features are available only if programmed Programmable Option Switches Power Switch Volume Down ...

Page 19: ...omatically resumes when the temperature returns to the normal range Busy Indicator Indicates the currently selected channel is busy see Section 3 4 4 Bell Indicator Appears or flashes when a 5 tone call is detected that the transceiver is programmed to receive Monitor Indicator Indicates that the monitor mode is enabled This mode disables coded squelch control so that all messages occurring on the...

Page 20: ... Proceed as follows 1 Select the power on menu by turning power on with the up and down keys pressed 2 The F1 F4 keys now control the following func tions Press the switch once to select the function and then again to return to the normal channel display F1 Minimum volume level see Section 3 3 3 F2 Key beep on off see Section 3 5 4 F3 Backlight on off see Section 3 5 2 F4 Squelch adjust see descri...

Page 21: ...ne calls With tele phone calls the telephone number can be dialed using a microphone with a telephone keypad or up to seven telephone numbers also may be preprogrammed and then selected by pressing the key see descrip tion in Section 3 5 7 3 4 2 RECEIVING A CALL 1 Turn transceiver power on and set the volume level as described starting in Section 3 3 1 2 Select or scan the channel or channels on w...

Page 22: ...l from being kept busy for an extended period by an accidentally keyed transmitter It can also prevent pos sible damage to the transceiver caused by transmitting for an excessively long period There is also a penalty timer that may be pro grammed to prevent further transmissions for the pro grammed time after the transmitter is disabled 3 5 PROGRAMMABLE FUNCTIONS 3 5 1 INTRODUCTION The F1 F4 and k...

Page 23: ...in Once emergency transmission begins the call cannot be canceled Pro gramming determines the channel on which the call is transmitted and also if it is transmitted once or repeat edly until a control code is received 3 5 9 LOCK KEY Press and hold the key to lock all pro grammable keys except and Either LK ON or LK OF is displayed to indicate the current condition If a locked key is pressed all th...

Page 24: ...te the current mode Each channel can also be programmed for wide or narrow band operation and this switch toggles that setting However the change is only temporary because the programmed condition is reselected if the channel is changed or power is cycled 3 6 CHANNEL SCAN 3 6 1 INTRODUCTION The channel scan feature monitors the channels in the current scan list When a message is detected that the ...

Page 25: ...ING Priority channel sampling ensures that messages on priority channels are not missed while listening to messages on other channels If priority sampling is used a priority A channel is designated by program ming If the key is available pressing that key selects the priority A channel This key also may be programmed so that if it is pressed and held the prior ity A channel changes to the current ...

Page 26: ...0 031 and Adapter Cable Part No 585 7600 031 are required to connect the computer to the transceiver The program ming cable has a female DB9 connector which plugs into the serial port of the computer In this connector is a level converter circuit which converts the RS 232 levels of the computer to the logic levels required by the transceiver The other end of the cable plugs into the adapter cable ...

Page 27: ... the various parameters is available in the form of help screens To display information on the currently highlighted function or setting press F1 Pressing ALT or ESC selects the menu on top or returns to the previous screen keys or highlighted character keys move the cursor The Space or backspace key toggle the setting Use the File menu to save the data and exit the program 4 4 MENU FLOW 4 4 1 INT...

Page 28: ...ameters for each scan list 2 Tone Code Channel Displays the screen shown in Table 4 6 which programs transceiver operation with a 2 tone option The optional 2 5 Tone Decoder Kit Part No 585 7500 026 is required to use the 2 tone function This screen is displayed with LMR models only see Section 4 4 6 LMR U S Format Common Displays the screen shown in Table 4 7 which programs miscellaneous informat...

Page 29: ...e Select the color or monochrome 1 or 2 display modes RS 232C Selects the computer serial port being used to connect the computer to the transceiver Table 4 1 Memory Channel Screen Description LMR Models Parameter Description Bank Select Up to 32 channels or two banks of 16 channels can be programmed To program the channels as two banks first program the MR CH Bank Free parameter in the Key and Di...

Page 30: ...space to disable transmitting on the channel Inhibit is then displayed F8 and F9 can be used to cut and paste frequencies Press Enter when the desired frequency has been entered CTCSS DTCS Rx Tx Enters the receive and transmit tone CTCSS Call Guard frequency or digital DTCS Call Guard code Press Enter to display the tone selection table Select a tone by scrolling to it and pressing Enter Press the...

Page 31: ...ggle the inhibit status Scan list programming is inhibited when parentheses are displayed around the numbers or underline characters Auto Reset If PWR ON Scan is enabled in the Scan screen see Table 4 5 this selects the time delay before scanning resumes after a call is complete the signal disappears or a key is pressed Either Timer A or Timer B can be selected These timers are programmed in the C...

Page 32: ...n Off see Table 4 5 It starts and stops scanning with no auto restart If the trans mitter is keyed during scanning the scan mode is exited Power On Scan On It stops scanning only until the Auto Reset Timer expires see Table 4 7 If the transmitter is keyed during scanning scan automatically resumes when the Auto Reset Timer expires Scan B Power On Scan Off or On It starts and stops scanning with au...

Page 33: ...en described in Table 4 3 Emergency Single Repeat EMER Pressing this key transmits an emergency call If Single is programmed it is transmitted only once if Repeat is programmed it is transmitted repeatedly with LMR models or until the proper 5 tone code is received with PMR models The emergency channel is specified by the CH Atr parameter on the Memory Channel screen described in Table 4 1 A DTMF ...

Page 34: ...unds for 2 seconds when power is turned on If no text is pro grammed no tone sounds and no message is displayed The characters and other information described for TEXT in Table 4 1 also applies to this text Table 4 3 DTMF Autodial Screen Description This screen is used to program the DTMF autodial codes that can be transmitted by pressing the DTMF key see Table 4 2 Each location can contain up to ...

Page 35: ...selected by the SCAN key also described in Table 4 2 Scanning may be enabled at power on see following and by placing the microphone on hook see Hanger Action in Table 4 2 Scan Mode The following conditions are programmable Scan Off Deactivates that scan list so that it cannot be selected M1 Normal Selects normal non priority scanning from the lowest to highest channel M2 Prio A Selects scanning f...

Page 36: ...busy channel and 3 transmits the 5 tone codes Table 4 6 2 Tone Code Channel Screen Description Parameter Description Rx Freq 1st 2nd Sets the frequencies for the first and second tones from 250 3300 Hz The closest tone is selected Group Call Programs if the 1st or 2nd tone is used for the group code Text Programs the text that is displayed when a matched 2 tone is received The characters and other...

Page 37: ... On Password setting Scan When a matched 2 tone is received scan is set to the following condition that is programmed Null Scan condition is not affected Cancel Scan is cancelled Start Scan is started See also Scan key in Table 4 2 and Power On Scan in Table 4 5 Parameter Description Rx Code Common Screen Notone Timer This item sets the acceptable period between 2 tones When received tones are int...

Page 38: ...ey To disable the Auto Reset function set one of these timers to Off 0 and select it in the channel screen Inactive Timer This feature is available with the PMR European mode only It sets the time in seconds to return to the Inaudible mode after the Audible mode is selected To turn off the inactive timer function do not assign Inactive in the channel screen TOT Timer Programs the time out timer ti...

Page 39: ...s still possible with this enabled Table 4 8 Expert Screen Description Parameter Description Fast Scan Timer Sets the period in seconds that each channel not programmed for CTCSS DTCS Call Guard squelch is scanned NOTE An appropriate time is set by default and if a time less than the default is programmed busy channels may not be detected Slow Scan Timer Sets the period in seconds that each channe...

Page 40: ...ff enables CTCSS DTCS Low Beep Frequency Sets the low beep tone frequency for 400 2998 Hz The nearest available frequency is automatically selected High Beep Frequency Sets the high beep tone frequency for 400 2998 Hz The nearest available frequency is automatically selected Character Editor Special characters can be designed using this function by enabling the available 14 segments in any combina...

Page 41: ...led the transceiver does not go into the clone mode The programming of this parameter does not affect the ability to receive data Therefore it can be in either mode in the slave target transceiver Set Mode Access Enabled This must be pro grammed to allow the Dealer Set mode to be accessed so that cloning can be enabled Dealer Passcode This six digit code must be known to enable the Dealer Set mode...

Page 42: ...sceiver on Then momentarily press the POWER switch of the master transceiver to begin the data transfer 6 When cloning is complete CLONE is displayed by the master and CLONE OK by the slave 7 To clone another transceiver repeat this procedure starting with step 4 8 To return both the transceivers to normal operation reconnect the microphone and cycle power Figure 4 2 Memory Channel Screen PMR Mode...

Page 43: ...PROGRAMMING 4 18 November 1998 Part No 001 7600 001 This page intentionally left blank ...

Page 44: ...tune them to the center frequency of the RF passband This gives a wide band width receiver good image response rejection The diodes are controlled by the CPU IC1 via level controller IC5 5 1 3 FIRST MIXER AND FIRST IF CIRCUITS The first mixer circuit converts the received sig nal to a fixed frequency first IF signal of 31 050 MHz The RF signal from the bandpass filter is applied to the first mixer...

Page 45: ...PF line When AFHPF is high the cut off frequency is shifted higher to attenuate the Call Guard CTCSS or DTCS signals The filtered output signal on IC8 pin 7 is applied to limiter IC7b and buffer IC7c De emphasis is pro vided by R145 and C182 The audio signal is then applied to pin 16 of level controller IC5 This device allows the CPU to control the speaker volume level The level controlled signal ...

Page 46: ...his signal is then applied to high pass fil ter IC8a b which attenuates frequencies in the Call Guard CTCSS DTCS range This is the same filter used for receive audio filtering The signal is then fed to IC7b and IC7c which provide buffering and amplification Deviation limit ing is then provided by level controller IC5 The input to this device is pin 16 and the output is pin 15 The signal is then fe...

Page 47: ... the voltage applied to the collector of Q1 and the power control input of IC1 This reduces the output power produced by these devices 5 3 VHF PLL CIRCUIT 5 3 1 PLL CIRCUIT The PLL Phase Locked Loop circuit provides a stable 5 PPM receive first injection and transmit frequency The PLL circuit consists of PLL circuit IC2 a loop filter and reference oscillator A block dia gram of the PLL circuit is ...

Page 48: ...d by R5 regulator Q27 using the T5C signal from I O expander IC IC11 T5 Transmit 5V supply controlled by T5 regulator Q28 using the T5C signal from I O expander IC11 Pin No Port Name Description 1 VIN Input port for overvoltage detection from the vehicle power source 12 SCK Outputs clock signal to EEPROM IC3 PLL IC2 main unit and expanders IC5 IC11 main unit etc 13 SI Input port for the data signa...

Page 49: ...e bandpass filter control signals 11 T4 Output port for tunable bandpass filter control signal while receiving and power control signal while transmitting 14 REF Output port for reference frequency control voltage Pin No Port Name Description Pin No Port Name Description 4 T5C Outputs control signal for T5 and R5 regu lator circuits Q27 Q28 main unit High Transmitting 5 TMUT Outputs Tx mute switch...

Page 50: ...The filtered signal is then applied to the first mixer Q3 The tunable bandpass filters controlled by D7 D10 employ varactor diodes to tune them to the center frequency of the RF passband This gives a wide bandwidth receiver good image response rejection The diodes are controlled by the CPU IC1 via level controller IC12 5 5 3 FIRST MIXER AND FIRST IF CIRCUITS The first mixer circuit converts the re...

Page 51: ...ss filter IC6c IC6d The cut off frequency of this filter is controlled by the AFHPF line When AFHPF is high the cut off frequency is shifted higher to attenuate the Call Guard CTCSS or DTCS signals The filtered output signal on IC6d pin 14 is applied to pin 8 of AF switching circuit IC11 The switched output signal on IC11 pin 9 is then applied to pin 16 of level controller IC12 This device allows ...

Page 52: ...atter filter IC7a and then to pin 11 of switching circuit IC11 The output signal from IC11 on pin 10 is fed to pin 16 of level controller IC12 This device provides deviation control and is also used in the receive mode to provide volume control The level controlled output on pin 15 is fed to pin 3 of switching circuit IC11 The switched output MOD on pin 4 is then applied to the PLL circuit D21 whe...

Page 53: ...lightly and lowers the voltage applied to the collec tor of Q19 and the power control input of IC5 This reduces the output power produced by these devices 5 7 UHF PLL CIRCUIT 5 7 1 PLL CIRCUIT The PLL Phase Locked Loop circuit provides a stable 2 5 PPM receive first injection and transmit frequency The PLL circuit consists of PLL circuit IC2 a loop filter and reference oscillator A block diagram o...

Page 54: ...5V regulator Q12 Q13 R8 Receive 8V supply produced by R8 regulator Q10 Q11 using the TXC signal from I O expander IC13 T8 Transmit 8V supply controlled by T8 regulator Q8 Q9 using the TMUT signal from I O expander IC13 Pin No Port Name Description 1 VIN Input port for overvoltage detection from the vehicle power source 12 SCK Outputs clock signal to EEPROM IC3 PLL IC10 main unit and expanders IC12...

Page 55: ...unable bandpass filter control signals 11 T4 Output port for tunable bandpass filter control signal while receiving and power control signal while transmitting 14 REF Output port for reference frequency control voltage Pin No Port Name Description Pin No Port Name Description 4 TXC Outputs control signal for R8 regulator Q10 Q11 main unit High Transmit mode 5 TMUT Outputs control signal for T8 reg...

Page 56: ...eq range 146 512 MHz Impedance 50 ohms SWR Less than 1 2 1 Frequency counter Freq range 0 1 500 MHz Freq accuracy 1 ppm or better Sensitivity 100 mV or better FM deviation meter Freq range DC 520 MHz Measuring range 0 to 10 kHz Audio generator Freq range 67 3000 Hz Output level 1 500 mV Attenuator Power atten 50 or 60 dB Capacity 50W Standard Signal Generator SSG Freq range 146 520 MHz Output leve...

Page 57: ...ansceiver and save it to a disk file so that it can be reloaded after the adjustments are complete Test channels at the low middle VHF only and high ends of the operating band and High Low1 and Low2 RF output power are required to perform the adjustments in this section These test channels are listed in Tables 6 1 and 6 2 and they must be pro grammed as regular channels using the programming softw...

Page 58: ... Low1 007N DTCS Alternate 1 If the transceiver operates on only narrow or wide band channels program only channels 1 5 and program them for the type of channels used narrow or wide band If the transceiver operates on both wide and narrow band channels program additional channels 6 and 7 for the other type of operation 6 1 4 COMPUTER AIDED TUNING To make most adjustments described in the fol lowing...

Page 59: ...est setup using the test cable described in Sections 6 1 3 and 6 1 4 Start the program as described 3 Connect a DC power supply and a 50 ohm 50 watt antenna load to the transceiver see Section 6 1 1 VHF ADJUSTMENTS 6 3 PLL ADJUSTMENT VHF MODELS 1 Remove the bottom cover by removing four screws Connect a DC voltmeter to check point CP1 shown in Figure 6 4 2 Select the channel on the high end of the...

Page 60: ... to the antenna jack 2 Scroll to Power Hi on the screen and key the transmitter using the test cable switch Use the com puter adjust keys to set the following power Unkey the transmitter Repeat for the Low2 Test Ch 4 and Low1 Test Ch 5 power levels High Power 45 watts Test Ch 3 Low2 Power 25 watts Test Ch 4 Low1 Power 4 5 watts Test Ch 5 6 4 3 FM DEVIATION ADJUST 1 Connect an audio generator to th...

Page 61: ...select Test Ch 8 and also set the waveform on that channel see note in Table 6 1 6 5 RECEIVER ADJUSTMENTS VHF MODELS 6 5 1 BANDPASS FILTER ADJUST 1 Select the channel on the low end of the band Test Ch 2 146 050 MHz 2 Connect an RF signal generator to the antenna jack Set the output for the channel frequency at a level of 3 2 µV 97 dBm modulated with 1 kHz at the following deviation Wideband 30 kH...

Page 62: ...ss the computer adjust keys to increase the dis played number to the point where the receiver squelches Then slowly adjust the number down ward again until the receiver just unsquelches 6 5 3 BEEP TONE LEVEL This adjustment sets the volume of the beep tone that is heard when keys are pressed and at other times if it is enabled The computer setup used in the pre ceding steps is not required for thi...

Page 63: ...requency by pressing the computer adjust keys Unkey the transmitter 4 Press Enter again to select the second adjust chan nel Key the transmitter and adjust for the displayed frequency Unkey the transmitter and press Enter again to exit this function 6 7 2 OUTPUT POWER ADJUST 1 Select the high power channel at the low end of the band Test Ch 3 Connect a power meter to the antenna jack 2 Scroll to P...

Page 64: ...f setting a wideband channel 3 Key the transmitter and view the demodulated sig nal on the CRT of a communications monitor 4 Press the adjust keys on the computer so that the waveform appears as follows 5 If the transceiver operates on both narrow and wide band channels select Test Ch 7 and also set the waveform on that channel see note in Table 6 2 L23 PLL lock voltage adjustment CP1 PLL lock vol...

Page 65: ...nt panel as described in Section 3 3 6 1 Select the channel on the low end of the operating band Test Ch 2 channel with LB models and the 150 050 MHz channel with HB models 2 Connect a SINAD meter with a 4 ohm load to the external speaker jack 3 Connect an RF signal generator to the antenna jack Set it to the channel frequency with an output mod ulated with 1 kHz at the following deviation Wideban...

Page 69: ...äíçðåëê íêì LRGHý ëíé8ý7ìíæ íëëðêäíçðèåë íêë HQHUý5 ëí ý ë íëëðêäíçðåëé íêê LRGHý 1ëíë8ý7ìíæ íëëðêäíçðèèå ì 7 ý ðëåèýõêìïíèíý0 ô íëëðêäíçðåëç ê HUDPLFý6 3 éèí ð7 íì íëëðêäíçðåëæ 5HIý1Rï HVFULSWLRQ 3DUWý1Rï é HUDPLFý6 3 éèí ð7 íì íëëðêäíçðåëå ííì ý0çåæíë íëëðêäíçðæäë ííë 3 êìéí 6ð ìýõ 6åô íëëðêäíçðèèé ííê 7 êììêç 1ýõ ñ ô íëëðêäíçðêíë ííé 8éíçç 9ð ì íëëðêäíçðèèè ííè 0çëêçê 3ðçèí íëëðêäíçðåêë ííç 1 0...

Page 71: ... ê ýìèëý9ýõìïèýNýRKPô íëëðêäíçðìèè 5ìíé 5HVý 5 ê ýìííý9ýõìíýRKPô íëëðêäíçðìêå 5HIý1Rï HVFULSWLRQ 3DUWý1Rï 5ìíè 5HVý 5 ê ýìèêý9ýõìèýNýRKPô íëëðêäíçðìçè 5ìíç 5HVý 5 ê ýìèêý9ýõìèýNýRKPô íëëðêäíçðìçè 5ìíæ 5HVý 5 ê ýëëêý9ýõëëýNýRKPô íëëðêäíçðìçæ 5ìíå 5HVý 5 ê ýëëêý9ýõëëýNýRKPô íëëðêäíçðìçæ 5ìíä 5HVý 5 ê ýìíêý9ýõìíýNýRKPô íëëðêäíçðìçê 5ììí 5HVý 5 ê ýéæêý9ýõéæýNýRKPô íëëðêäíçðìæì 5ììì 5HVý 5 ê ýìíìý9ýõìí...

Page 72: ...Pýõìíëô íëëðêäíçðåçå 5ìäå 5HVý 5 ê ýéæêý9ýõéæýNýRKPô íëëðêäíçðìæì 5ìää 5HVý 5 ê ýéæëý9ýõéïæýNýRKPô íëëðêäíçðìçí 5HIý1Rï HVFULSWLRQ 3DUWý1Rï 5ëíí 5HVý 5 ê ýéæêý9ýõéæýNýRKPô íëëðêäíçðìæì 5ëíì 5HVý 5 ê ýìíëý9ýõìýNýRKPô íëëðêäíçðìèé 5ëíë 5HVý 5 ê ýìíêý9ýõìíýNýRKPô íëëðêäíçðìçê 5ëíê 5HVý 5 ê ýéæëý9ýõéïæýNýRKPô íëëðêäíçðìçí 5ëíé 5HVý 5 ê ýìíëý9ýõìýNýRKPô íëëðêäíçðìèé 5ëíè 5HVý55íåìç5ðêíéð ýõêííýNýRKPô í...

Page 73: ...37ýõéííðéæíý0 ô íëëðêäíçðäìí HUDPLFý 50éëðçý ýíêí ý èíí37ýõéæíðèìëý0 ô íëëðêäíçðäíè íìè HUDPLFý ìçíåý ýì ýéæí ð7ð íëëðêäíçðçíí íìç HUDPLFý ìçíåý ýì ýéæì ð7ð íëëðêäíçðíèä íìæ HUDPLFý 50éëðçý ýíëí ý èíí37ýõéäíðèìëý0 ýRQO ô íëëðêäíçðæäè HUDPLFý 50éëðçý ýíåí ý èíí37ýõRWKHUýEDQGVô íëëðêäíçðåìä íìå HUDPLFý ìçíåý ýì ýë5è ð7ð íëëðêäíçðíæì íìä HUDPLFý ìçíåý ýì ýìíë ð7ð íëëðêäíçðíçí íëí HUDPLFý ìçíåý ýì ýì5...

Page 84: ... 4íé 7UDQVLVWRUý 7 ìéé78ý7ìíæ íëëðêäíçðèæë 4íè 7UDQVLVWRUý 3éçíìýõ7 ô íëëðêäíçðêëå 4íç 7UDQVLVWRUýë6 éíåìý7ìíæý5 íëëðêäíìðêéê 4íæ 7UDQVLVWRUýë6 éíåìý7ìíæý5 íëëðêäíìðêéê 5íì 5HVý 5 ê ýìíêý9ýõìíýNýRKPô íëëðêäíçðìçê 5íë 5HVý 5 ê ýìíéý9ýõìííýNýRKPô íëëðêäíçðìæè 5íê 5HVý 5 ê ýëëéý9ýõëëíýNýRKPô íëëðêäíçðìæå 5íé 5HVý 5 ê ýìíéý9ýõìííýNýRKPô íëëðêäíçðìæè 5íè 5HVý 5 ê ýìëêý9ýõìëýNýRKPô íëëðêäíçðìçé 5íç 5HVý...

Page 86: ... MP2 F DS1 F EP2 F MP1 F FRONT UNIT W3 F J1 F MP7 C MP1 C MP7 C MP7 C MP4 M MP1 M MP2 M MP13 C MP7 C MP5 M MP6 C MP7 C MP11 C MP12 M W7 M J5 M MP6 C MP5 C MAIN UNIT Bottom side MP3 M MP7 C J1 C MP9 C SP1 C MP8 C MP7 C MP4 C WS1 C VHF 7610 EXPLODED VIEW ...

Page 87: ...UHF 7640 EXPLODED VIEW 7 22 November 1998 Part No 001 7600 001 FOLDOUT VHF Exploded View ...

Page 88: ...3 4 5 6 7 8 9 10 11 12 13 14 15 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 GND 5V HV MICMUTE AFONOP BEEPOUT RXMUT DET AFOUT REM OPCS OPINT SO SI SCK MICOUT MICIN BUSY MOWN SIGOUT OPT1 OPT2 OPT3 OPV3 OPV2 OPV1 J2 OPT X X EXTONE IN PTTOUT PTTIN MMUT CTRL RMUT CTRL 5V SO SCK EXST EXEN NWC AFHPF AFATT HORNO TMUT T5C MMUT RMUT IC11 M M R M D25 D26 EXP CPU VIN TEMP LVIN SO DIMIN EXPTT PTTIN UNLK NOIS ...

Page 89: ...VHF 7610 Transistor Basing Diagrams VHF 7610 Diode Basing Diagrams 8 2 November 1998 Part No 001 7600 001 ...

Page 90: ...8 3 November 1998 Part No 001 7600 001 VHF 7610 MAIN BOARD BOTTOM VIEW FOLDOUT ...

Page 91: ...8 4 November 1998 Part No 001 7600 001 VHF 7610 MAIN BOARD TOP VIEW ...

Page 92: ...3 1 2 11 4 R236 100k C287 100p R234 100k D31 DA204U R178 33k IC7a NJM2902V R238 18k 8V CPU5V GND OPINT OPCS BUSY BEEPOUT TONE BEEP DTCS RFATT NOIS UNLK EXEN EXST DAST PLST VIN TEMP MIC 5V AFO SI OPT3 OPT2 OPT1 OPV3 OPV2 OPV1 PTT PTTIN DET PWON EXPTT DIMIN SO SCK SD LVIN GND J1 R212 EXB V8V 1kX4 R213 EXB V8V 1kX4 R214 EXB V8V 1kX4 R215 EXB V8V 1kX4 R216 EXB V8V 1kx4 R217 EXB V8V 1kx4 R219 EXB V8V 1...

Page 93: ...RM CPU5V RMUT CTRL D24 Q37 R8V T8V TXC R8V 5V 5V CTRL Q12 Q13 T8V Q8 Q9 D14 CPU5V MMUT MIMUT MM RXMUT MMUT CTRL D25 Q46 TMUT COMMON LINE LINE RX LINE TX LINE DATA BUS LINE DIM HORN DISC HV AFO IN PTT DIM SW Q38 HORN SW Q39 1 2 3 4 5 6 7 8 9 10 11 J5 OPV1 OPV2 OPV3 GND OPT3 OPT2 OPT1 BUSY AUX SCK SI SO GND 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 J4 SIGOUT MI...

Page 94: ...8 7 November 1998 Part No 001 7600 001 UHF 7640 MAIN BOARD BOTTOM VIEW FOLDOUT ...

Page 95: ...35 R134 C161 R139 R138 C165 L31 C164 C162 L30 Q30 R136 C163 R123 C150 C151 R125 R124 W 9 Q25 C152 C153 C154 C312 L14 C45 C44 L13 R32 C303 FI1 FI2 FI3 IC6 R95 R96 R94 C126 C127 R99 C129 R100 C128 R147 C130 R101 X1 R47 R45 R44 C61 C63 C58 R48 C57 C62 R46 R40 C56 R41 C52 IC1 C51 C50 R36 C49 L15 FI1 C282 C295 C242 C241 C178 R213 R214 R215 R218 R217 R216 J6 1 J2 To Spkr J5 To Opt Cable 15 16 30 2 39 40...

Page 96: ...0047 R279 82k only R162 470k C179 0 1 R161 470k 7 6 5 R148 100k R147 10k R146 82k R144 22k R145 75k C174 0 1 C175 0 1 C176 2 2 R141 10k R268 10k R269 39k R142 10k TONE DTCS C335 47p C323 10p W13 W16 W15 W14 C173 12p L32 0 56µH C170 5p C171 4p C172 5p L33 0 56µH C169 12p R127 4 7k 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 5V AFO S...

Page 97: ...C71 C46 C70 C10 W2 R11 C36 R28 R25 R24 R27 R26 C38 R30 C39 R29 R31 R40 R39 R68 R58 C45 R42 R49 R41 C29 R20 R50 C82 C33 C30 R69 R57 C34 C32 R21 R22 C35 C58 C69 C27 C26 R59 C28 R55 R15 R4 C15 R1 R14 C12 W1 L3 IC3 IC2 D1 X1 IC1 R45 R44 R48 R46 R17 C9 C14 Q1 R47 C37 L1 Q4 D2 D3 D4 Q7 Q10 Q5 100 1 25 26 50 51 75 76 D5 J2 Q3 D6 Q6 1 2 39 40 J2 To Main Unit 40 8V 38 CPU5V 36 GND 34 OPINT 32 OPCS 30 BUSY ...

Page 98: ...CLOUT POSW R64 1k R63 1k R62 1k R55 100k KR0 KR1 KR2 KR3 KS0 KS1 DIM R67 100k R66 100k R65 100k R54 1k R48 EXB V8V 1kx4 R46 EXB V8V 1kx4 MTONE DTMF OPV3 OPV2 OPV1 CTCIN SD LVIN TEMP VIN KR0 KR1 KR2 KR3 R17 EXB V8V 1kx4 KS0 KS1 R19 470 R18 470 R59 1k C28 0 001 S6 C22 47p C23 47p C24 47p C25 47p C26 47p C27 47p DIM D6 MA8051 Q3 DTA143ZU R11 820 1 R16 2 2k R15 2 2k R14 390 R12 390 DS10 DS11 DS2 DS3 D...

Page 99: ...BJ 2SK880 GR Symbol XG DTA143ZU Symbol 113 DTA144EU Symbol 16 DTC114EU Symbol 24 DTC144EU Symbol 26 DTC144TU Symbol 06 DTC363EK Symbol H27 XP4601 Symbol 5C XP6501 Symbol 5N E C B D S G S D G S D G S D G S G D D S G2 G1 D S G2 G1 1SS302 Symbol C3 DIODES 1SS352 Symbol C1 1T365 Symbol pink line N DA221 Symbol K DAN202U Symbol N DAN204U Symbol K MA713 Symbol MIN HVU350 Symbol 4 MA77 Symbol 4B MA111 Sy...

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