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Daniels Electronics Ltd. A21-TX3-00, Instruction Manual

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Daniels Electronics Ltd. A21-TX3-00 Instruction Manual Download Page 23

LED ENA

X

X

X

Y

Y

Y

Y

X

X

Y

B20

J16

RELAY1

J2

12

13

11

U2d

U2c

D32

D20

+9.5VDC

+9.5 VDC

2

1

3

U2a

J17

JP1-2

+9.5 VDC

Z20

B4

Z4

B22

Z18

B18

Z24

Z28

B12

Z12

B10

Z10

B14

Z14

B24

D12

D2

B8

Z8

D8

D10

J1

D30

D28

D22

D24

D26

Z22

B26

Z26

Z30

B32

Z32

B30

D6

D4

Y

X

J4

X

Y

+9.5V

+9.5V OUTPUT

GROUND

MIC PTT WTO

MIC PTT NTO

MIC AUDIO

MT-3 FRONT PANEL BOARD

RX AUDIO / +13.8V 

B2

Z2

+13.8VDC

B6

Z6

RF OUT

REFERENCE

INPUT

OC-3 CRYSTAL CONTROL MODULE

OR 

OS-3 SYNTHESIZER MODULE

R

FRONT PANEL
N CONNECTO

RF IN

RF OUT

+9.5V

+13.8V

FOR

REV

ENA

MT-3 VHF/UHF AMPLIFIER MODULE 

OR

LED ENA

+9.5VDC

PTT TRIGGER

PTT WTO
TRIGGER

+9.5VDC

SWITCHING 
CIRCUITRY

+9.5VDC

VSWR REVERSE

FORWARD POWER FAIL
INDICATOR

10-17 VOLTS
+ 13.8 VDC NOMINAL

BACKPLANE
CONNECTOR

GROUND

GROUND

GROUND

GROUND

RX DATA IN

TX DATA OUT

BOOTSTRAP

CHANNEL SEL 0 (LSB)

CHANNEL SEL 1

CHANNEL SEL 2

CHANNEL SEL 3 (MSB)

TX AUDIO CONTROL

+9.5 VDC PTT SWITCHED

J12

R25
27K4

R26
1K0

Q10
PZT2222A

J14

J15

J13

FUSE
(OPTIONAL)

+9.5 VDC CONTINUOUS

J9

SQL DE-EMP
INPUT

MIC OUT

MIC IN

BALANCED INPUT
SIDE 2

600 OHMS

BALANCED INPUT
SIDE 1

SUBTONE
INPUT #1

SUBTONE
INPUT #2

SQL FLAT
INPUT

DIRECT MOD
INPUT

PTT WTO

TX 
STANDBY

NO2

COMMON 2

NC2

RLY POS

RLY NEG

NC 2

NC 1

COMMON 1

PTT NTO

PTT OUTPUT

PTT OUTPUT

TX STANDBY

PTT

+ 9.5 VDC PTT SWITCHED

+ 9.5 VDC SWITCHED

J3

Y

X

J7

+ 9.5 VDC PTT 
SWITCHED

+ 9.5 VDC 
SWITCHED

8

10

9

1

7

9

8

10

4

2

3

0 1

2

3

4

5

6

7
8

9

0 1

2

3

4

5

6

7
8

9

0 1

2

3

4

5

6

7
8

9

0 1

2

3

4

5

6

7
8

9

MSB

LSB

T1

600

Ω

PTT

Y

X

J18

+ 9.5 VDC PTT 
SWITCHED

+ 9.5 VDC 
SWITCHED

PTT OUTPUT

8 VDC

SUPPLY

+9.5 VDC

Y

X

Y

X

Y

X

Y

X

J20

J22

J23

J19

AUDIO OUTPUT

SUBTONE #2 OUTPUT

MICROPHONE
INPUT

BALANCED INPUT

+9.5V

+8.0V SWITCHED

TONE/DIGITAL INPUT

SUBTONE #1 INPUT

SUBTONE #2 INPUT

DIRECT MODULATION INPUT

GND

MT-3 AUDIO 
PROCESSOR  

AUDIO CONTROL 

 AM(N/C)

 AM(N/C)

 AM(N/C)

 AM(N/C)

 AM(N/C)

 AM(N/C)

TOT INPUT 

TOT OUTPUT 

J35

J33

TOT INPUT 

TOT OUTPUT 

TIME OUT       

TIMER

J25

JP1-7

JP1-7

J25 PIN 3

DE

DANIELS

ELECTRONICS

VICTORIA B.C .

DATE.:

DWN:

DWG No:

TITLE:

APRVD:

BOARD NO.:

BOARD REV.:

DWG REV DATE:

DE

DANIELS 

ELECTRONICS 

MT3TXMNM1C

5 

ILLUSTRATIONS AND SCHEMATIC DIAGRAMS

5.1 

Transmitter Block Diagram

5-1

MT-3 AM Transmitter Main Board Instruction Manual

MT-3 TRANSMITTER BLOCK DIAGRAM

SHANE AEBISCHER

43-920917

1.7

19 JULY 1994

9 OCTORBER 1998

Summary of Contents for A21-TX3-00

Page 1: ...reproduced stored in a retrieval system or transmitted in any form or by any means electronic mechanical photocopying recording or otherwise without the prior written consent of Daniels Electronics Ltd DE is a registered trademark of Daniels Electronics Ltd registered in the United States Patent and Trademark Office Issue 3 Previous Issue 2 Issue Date December 98 Previous Issue Date March 98 Danie...

Page 2: ...nature Date NOTE The user s authority to operate this equipment could be revoked through any changes or modifications not expressly approved by Daniels Electronics Ltd The design of this equipment is subject to change due to continuous development This equipment may incorporate minor changes in detail from the information contained in this manual ...

Page 3: ... 3 2 1 3 Audio Circuits 2 4 2 1 3 1 Microphone Audio 2 5 2 1 3 2 Received Audio 2 5 2 1 4 Channel Selection 2 5 2 1 4 1 Synthesized Transmitter 2 5 2 1 4 2 Crystal Controlled Transmitter 2 5 2 1 5 Amplifier Circuits 2 6 2 2 MT 3 Front Panel Board 2 6 2 3 MT 3 AM Audio Processor 2 6 2 3 1 General 2 6 2 3 2 Power Requirements 2 6 2 3 3 Audio Circuitry 2 7 2 3 4 PTT Time Out Timer 2 8 3 TRANSMITTER A...

Page 4: ...MT 3 AM Transmitter Main Board Component Layout Bottom 5 4 5 2 3 MT 3 AM Transmitter Main Board Schematic Diagram 5 5 5 3 MT 3 Front Panel Board 5 6 5 3 1 MT 3 Front Panel Board Component Layout 5 6 5 3 2 MT 3 Front Panel Board Schematic 5 7 5 4 MT 3 AM Audio Processor Electrical Assembly 5 8 5 4 1 MT 3 AM Audio Processor Component Layout 5 8 5 4 2 MT 3 AM Audio Processor Schematic Diagram 5 9 6 P...

Page 5: ...ain Board and are routed to the other modules The front and rear back plates are attached to the Transmitter Main Board and together with the extruded aluminum shell as discussed in the assembly section of the Transmitter Manual form the transmitter enclosure 1 2 Performance Specifications 1 2 1 General Type MT 3 AM Series Transmitter Compatibility VT 3A Series Amplifier OCT 3 Crystal Oscillator O...

Page 6: ...in Board Instruction Manual 1 2 2 Audio Specifications Audio Input 30 to 0 dBm into a 600Ω balanced load Audio Response Flat audio 1 3 dB 300 Hz 3 kHz Audio Distortion Less than 3 40 C to 60 C at 30 modulation Less than 5 40 C to 60 C at 90 modulation ...

Page 7: ...ush To Talk PTT inputs that key the transmitter are active low 2 0 Vdc One PTT input is on the front panel microphone connector The other two PTT inputs PTT WTO PTT With Time Out Timer and PTT NTO PTT No Time Out Timer are on the backplane connector of the transmitter board If required the microphone s PTT input can be configured to activate the transmitter s Time Out Timer TOT An isolated PTT inp...

Page 8: ... NTO signal which is normally high falls below 2 0 Vdc the transmitter is keyed As long as the PTT NTO signal remains below 2 0 Vdc the transmitter will remain keyed The transmitter is disabled when the PTT NTO signal rises above 2 3 Vdc The PTT NTO threshold of approximately 2 Vdc 0 3 Vdc hysteresis is set by U1b R5 R6 R7 R8 R9 and R10 while diodes D3 and D4 provide overvoltage protection for U1b...

Page 9: ... all of the PTT inputs When the transmitter is keyed Q1 is turned off and subsequently transistors Q3 Q4 and Q6 are turned on Transistors Q3 Q4 and Q6 provide three different functions Q3 provides the active low signal for the synthesizer or crystal module PTT input Q4 turns on Q5 which turns on the 9 5 Vdc Switched supply Q6 turns on Q7 which turns on the 9 5 Vdc PTT Switched supply The 9 5 Vdc S...

Page 10: ... Synthesized typically 19 mA Crystal Controlled typically 11 mA start up time Synthesized typically 40 ms Crystal Controlled typically 8 ms MODE 4 Jumper J6 in jumper J7 in the x position jumper J18 in the x position the audio processor is enabled all of the time the synthesizer or crystal module is enabled all of the time standby current Synthesized typically 163 mA Crystal Controlled typically 2...

Page 11: ... 1 Synthesized Transmitter Eight backplane connections are used to communicate with the synthesizer unit Pins D28 D30 and D32 are used in house to program the synthesizer Channel select lines pins D20 D22 D24 and D26 are used once the synthesizer is programmed to select one of 16 channels If the channel select lines are all low channel 0 the channel for the synthesizer is read from switches FSW1 m...

Page 12: ...x position MIC PTT NTO no time out timer factory setting y position MIC PTT WTO with time out timer Refer to section 5 3 2 MT 3 Front Panel Board Schematic Diagram 2 3 MT 3 AM Audio Processor 2 3 1 General The MT 3 AM Audio Processor is a versatile circuitboard that can provide several types of audio processing The module also has an on board programmable push to talk PTT time out timer TOT on an ...

Page 13: ...the input level say a 20 dB drop in input level will produced a 20 dB increase in gain The output will remain fixed at a constant level without clipping and distortion Automatic Level Control The input signals are adjusted by the pots R1 R16 The variable gain cell in U1a is used as a voltage controlled amplifier so that if the power supply 13 8Vdc has changed the output level will change in order ...

Page 14: ...low again in order to rekey the transmitter The time out duration is jumper selectable from 1 second to 8 hours The table below shows the time out duration in minutes for the various jumper settings which are listed as enabled E jumper shorted in or disabled D jumper left open out The standard factory setting of 5 minutes is shown in bold type in the table below D DISABLED no solder jumper install...

Page 15: ...tive ESD protection 3 3 Printed Circuitboard Numbering Convention To ease troubleshooting and maintenance procedures Daniels Electronics Limited has adopted a printed circuitboard PCB numbering convention in which the last two digits of the circuitboard number represent the circuitboard version For example PCB number 43 912010 indicates circuitboard version 1 0 PCB number 50002 02 indicates circui...

Page 16: ...J2 x position Optional relay configuration Jumper J3 not installed Optional relay configuration Jumper J4 y position Optional relay configuration Jumper J6 installed Transmitter standby mode select Mode 3 Jumper J7 x position Audio processor standby mode select Jumper J9 not installed Receiver audio ac dc input coupling Jumper J12 not installed Not applicable Jumper J13 not installed Not applicabl...

Page 17: ...omatic Level Control enabled Jumper JU4 not installed Time out time power supply optional Jumper JU5 y position Voice application Jumper JU6 y position Voice application Jumper JU7 not installed Modulation configuration Jumper JU8 y position Automatic Level Control enabled Jumper JU9 installed Power AMC and Microphone enabled 3 6 MT 3 AM Transmitter Board Alignment 3 6 1 General Before proceeding ...

Page 18: ...TP19 audio processor continuous 9 5 Vdc TP20 not used TP21 audio processor supply 8 Vdc selected by J7 TP22 not used TP23 synthesizer receive data line 0 Vdc TP24 synthesizer transmit data line 5 Vdc TP25 Q1 collector inactive 0 Vdc active 9 5 Vdc TP26 U2d output inactive 9 5 Vdc active 0 Vdc TP27 U1a output PTT WTO inactive 9 5 Vdc active 0 Vdc TP28 U1b output PTT NTO inactive 9 5 Vdc active 0 Vd...

Page 19: ...onent layout is shown in section 5 4 1 3 8 2 MT 3 AM Audio Processor Adjustment note clockwise rotation of controls increase signal levels 1 Before adjusting the audio board confirm that the transmitter frequency is correct 2 Unscrew and slide out the case of the transmitter Locate the Tx Audio Board 3 Connect the transmitter RF Output to a Radio communications test set 4 Connect the 600 ohm input...

Page 20: ...main at the same level of 90 7 and distortion should be less then 3 If not adjust the pot R4 on the Audio Processor Board to achieve this This step verifies the correct operation of the AMC 13 Repeat steps 7 and 9 if required 14 Supply a 1 kHz 10 dBm signal to the microphone input Note the level restriction of 25 dBm to 0 dBm 15 Adjust the Microphone Input Level Adjust pot R1 to achieve 50 of RF s...

Page 21: ...N C B8 Relay Positive Z8 Relay Negative D10 N C B10 PTT WTO Z10 PTT WTO D12 N C B12 Tx Standby Z12 Tx Standby D14 N C B14 PTT NTO Z14 PTT NTO D16 N C B16 No Connect MT 2 9 5V Z16 No Connect MT 2 9 5V D18 N C B18 Balanced Input 2 Z18 Balanced Input 1 D20 Channel Select 0 LSB B20 Squelched De emph Audio Z20 Squelched Flat Audio D22 Channel Select 1 B22 Subtone Input 1 Z22 Tx Audio Control D24 Channe...

Page 22: ...DE DANIELS ELECTRONICS 4 2 MT 3 AM Transmitter Main Board Instruction Manual This Page Intentionally Left Blank ...

Page 23: ... SIDE 2 600 OHMS BALANCED INPUT SIDE 1 SUBTONE INPUT 1 SUBTONE INPUT 2 SQL FLAT INPUT DIRECT MOD INPUT PTT WTO TX STANDBY NO2 COMMON 2 NC2 RLY POS RLY NEG NC 2 NC 1 COMMON 1 PTT NTO PTT OUTPUT PTT OUTPUT TX STANDBY PTT 9 5 VDC PTT SWITCHED 9 5 VDC SWITCHED J3 Y X J7 9 5 VDC PTT SWITCHED 9 5 VDC SWITCHED 8 10 9 1 7 9 8 10 4 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5...

Page 24: ...DE DANIELS ELECTRONICS 5 2 MT 3 AM Transmitter Main Board Instruction Manual This Page Intentionally Left Blank ...

Page 25: ...R42 OPT FSW4 BCD 10 FSW3 BCD 10 FSW2 BCD 10 FSW1 BCD 10 MSD LSD Components Not Installed 12B SYNTHESIZER GROUND TAB Low Power Synthesizer Only SYNTHESIZER GROUND TAB Low Power Synthesizer Only OS 3 RF OUTPUT OC 3 RF OUTPUT OS 3H ENHANCED SYNTHESIZER OR OC 3 CRYSTAL CONTROL MODULE OST 3H RF OUTPUT TP19 TP20 TP22 TP21 32 30 28 26 24 22 20 18 16 14 12 10 8 6 4 2 D B Z TP15 TP16 TP18 TP17 TP12 TP13 TP...

Page 26: ...6 LPF25 LPF24 LPF23 LPF22 LPF21 LPF20 LPF19 LPF18 LPF17 LPF16 LPF15 LPF12 LPF10 LPF8 LPF3 LPF5 LPF4 LPF2 LPF1 D8 BAS 16 y J3 x y J2 x x y J21 U6 LP 2951 y J7 x J14 y R29 82k5 x J13 y R5 10R0 J16 R110R0 R30 15k0 C15 4 7µF C14 10nF D7 BAS 16 M2 5 PRESS NUT x LPF14 C10 1 µF y J25 x R16 10k0 x y x y J20 J23 x y J19 J22 J24 x J15 y C20 4 7µF 16V U8 MC14536B R39 221K U7 33172 R32 1k00 R34 27k4 R33 68k1 ...

Page 27: ... TP27 2 3 1 MC33172 a U1 4 5 6 7 8 MC33172 b U1 BYD17J D3 27K4 R6 BYD17J D4 BAS16 D8 10R0 R5 1K0 R7 27K4 R8 TP28 10nF C6 100K0 R10 221K0 R9 9 5V 9 5V TP26 8 9 10 MC14081 c U2 13 12 11 MC14081 d U2 100nF C8 9 5V 5 6 4 14 7 MC14081 b U2 1 2 3 MC14081 a U2 9 5V G D S D15N06V Q9 E B C BC807 25 Q8 10K0 R18 TP11 E B C BC817 25 Q1 E B C BC817 25 Q3 9 5V 9 5V E B C BC817 25 Q4 BYD17J D5 BYD17J D6 J6 TP7 G...

Page 28: ...al 5 3 MT 3 Front Panel Board 5 3 1 MT 3 Front Panel Board Component Layout D1 MIC 1 2 3 4 PF2 SW1 PF1 c b a f e d KEYED NORM J1 Y X Solder Jumper On Solder Side Of PCB Factory Installed Solder Jumper MT3TXMNM5A PF3 J2 Y X 43 921212 P1 2 1 4 3 6 5 8 7 1 2 3 4 1 2 3 4 1 2 3 4 ...

Page 29: ...M6A 28 MAY 97 07 APRIL 1992 43 921212 MT 3 FRONT PANEL BOARD M GAUBE X Y PF3 3 PF3 4 PF3 1 PF3 2 X PF1 4 PF1 1 PF1 2 PF1 3 PF2 2 PF2 3 PF2 4 PF2 1 MIC 2 MIC 4 MIC 3 MIC 1 Y KEYED NORM D1 J1 C1 N I 1 2 3 4 MIC 1 2 3 4 PF1 PF2 4 2 1 3 PF3 1 2 3 4 5 6 7 8 P1 J2 F E D C B A SW1 9 5V IN LED ENA MIC PTT NTO MIC PTT WTO MIC INPUT MIC INPUT MIC PTT MIC PTT RX MON RX MON 9 5V OUT 9 5V OUT RX AUDIO RX AUDIO...

Page 30: ...utput Adjust R22 3K48 R25 82k5 R9 10k0 U2 MC33174 C23 220pF C19 1 0uF R18 470k0 DWG No VAP130AS2C TITLE TX AM AUDIO PROCESSOR SURFACE MOUNT DESIGNATIONS C7 10nF JU1 JU8 JU4 X Y JU7 DWG REV DATE MARCH 06 98 X Y JU3 Y X JU6 X Y JU5 X Y C22 680pF R28 82k5 JU2 C20 220pF C25 150pF C17 330pF R23 51k1 R32 51k1 R31 15k4 R24 15k4 R30 47k5 R20 39k2 R29 5k11 R19 5k11 C18 220pF R15 49k9 R3 49k9 C14 100nF JU9 ...

Page 31: ... DESIGNATORS APRVD FB1 C1 4 7nF CW R1 5K0 TP1 C2 470nF CW R4 50K0 TP2 Vcc Rect In Var G Rect Cap Output Inv In R3 THD Trim GND 2 3 1 7 5 6 8 13 4 a U1 SA571D Rect In Var G Rect Cap Output Inv In R3 THD Trim 15 14 16 10 12 11 9 b U1 SA571D R6 100K0 TP3 C3 680nF C6 100nF C7 10nF TP4 680nF C8 4 7uF C9 470nF C10 18K2 R13 CW R16 5K0 C12 4 7uF C13 1 0nF 470K0 R18 TP5 TP6 C21 4 7uF TP8 MT 3 TX TIME OUT T...

Page 32: ...5V 0V 2 4V 2 0V 2 2VDC 9 4VDC 2 9VDC 0 021VDC 0 135VDC APPROX 0 8 VDC 2 9VDC DWN BY MICHAEL GAUBE APRVD TITLE MT 3 TXTIME OUT TIMER SCHEMATIC DIAGRAM DWG REV DATE 16 JANUARY 1996 DATE 19 JANUARY 1996 DWG No MT3APM4 BOARD No 50027 02 BOARD REV VERSION 0 2 HIGHEST REFERENCE DESIGNATORS UNUSED REFERENCE DESIGNATORS C4 J8 Q1 R17 U2 J1 J4 C3 100nF R9 221k 100nF C4 R14 221k R15 221k R16 221k R13 221k R1...

Page 33: ...5A104K5R C22 CAP SM100nF CER 0805 X7R 50V 1008 5A104K5R C23 CAP 100nF FILM MMK5 10 63V 1016 5A104K63 D1 D6 DIODE BYD17J RECTIFIER SOD87 2101 BYD17J00 D7 DIODE BAS16 SWITCHING SOT23 2100 BAS16000 D8 DIODE BAS16 SWITCHING SOT23 2100 BAS16000 F1 FUSE 3AMP FAST BLO 1 1 4 IN 5604 5GAGC030 FSW1 4 SWITCH BCD 10 STEPS 5 PIN PCB 5273 10BCD001 J30 CONNECTOR F 48_MALE R A_P 3720 6048M0RA LPF1 35 FILTER SM LP...

Page 34: ...K0 0805 1 100ppm 1150 3A1001FP R28 RES SM NOT INSTALLED 0805 1 100ppm 1150 4A1502FP R29 RES SM 82K5 0805 1 100ppm 1150 4A8252FP R30 RES SM 15K0 0805 1 100ppm 1150 4A1502FP R31 RES SM221k 0805 1 100ppm 1150 5A2213FP R32 RES SM 1k00 0805 1 100ppm 1150 3A1001FP R33 RES SM 68k1 0805 1 100ppm 1150 4A6812FP R34 RES SM 27k4 0805 1 100ppm 1150 4A2742FP R35 RES SM 27k4 0805 1 100ppm 1150 4A2742FP R36 RES S...

Page 35: ...OLE NYLON BLACK 5671 250N062B 1 LOCKWASHER M3 SPLIT A2 STEEL 5814 3M0LK00S 4 MIC CONN 4 PIN MALE BLACK 5040 114ST0BK 1 NAMEPLATE BLANK 14HP ALUM 3702 10001214 1 NUT M2 5 HEX 5 0mm STEEL Ni 5813 2M5HX50N 2 NUT M2 5 SQUARE 5 0mm ZINC 5813 2M5SQ50Z 2 NUT PRESS M2 5 5 6mm OD PC MNT 5833 T2M55615 1 PANEL FRNT W IDENT TX EXTR VER 3802 61002101 1 PANEL REAR POS 4 14HP EXTRSN 3702 63002101 1 SCREW M3 x 8 ...

Page 36: ...74K63 C6 CAP SM 100nF CER 0805 X7R 50 1008 5A104K5R C7 CAP SM 10nF CER 0805 X7R 1008 4B103K5R C8 CAP SM 680nF TANT 10 35V 1055 4B684K35 C9 CAP SM 4 7uF TANT 10 16V 1055 5B475K16 C10 CAP 470nF FILM MMK5 10 63V 1016 5D474K63 C11 CAP SM 2 2uF TANT 20 20V 1055 5B225K20 C12 CAP SM 4 7uF TANT 10 16V 1055 5B475K16 C13 CAP SM 1 0nF CER 0805 X7R 50V 1008 3A102K5R C14 CAP SM 100nF CER 0805 X7R 50V 1008 5A10...

Page 37: ...ppm 1150 4A1822FP R14 POT SM 100K0 4mm SQ 100K 11T SIDE 1174 DM4104J0 R15 RES SM 49K9 0805 1 100ppm 1150 4A4992FP R16 POT SM 5K0 4mm SQ 11T SIDE 1174 DM2502J0 R17 RES SM 10K0 0805 1 100ppm 1150 4A1002FP R18 RES SM 470K0 0805 1 100ppm 1150 5A4703FP R19 RES SM 5K11 0805 1 100ppm 1150 3A5111FP R20 RES SM 39K2 0805 1 100ppm 1150 4A3922FP R22 RES SM 3K48 0805 1 100ppm 1150 3A3481FP R23 RES SM 51K1 0805...

Page 38: ...DE DANIELS ELECTRONICS 6 6 MT 3 AM Transmitter Main Board Instruction Manual This page intentionally left blank ...

Page 39: ...o the SM side of the PCB Moved P1 P2 P5 to the correct positions Added land pattern to the PCB for R21 3 June 98 Corrected the part number for D1 and D2 on the MT 3 AM Audio Processor Electrical Parts List December 98 The Butterworth filter stages were changed to Bessel filters to improve the differetnial group delay of the AM Transmitter ECO 563 The AM Audio Processor PCB was 50049 02 is now 5004...

Page 40: ...DE DANIELS ELECTRONICS 7 2 MT 3 AM Transmitter Main Board Instruction Manual This page intentionally left blank ...

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