Daniels Electronics Ltd. MT-3 Series Guide

DANIELS
DANIELS
ELECTRONICS LTD.
ELECTRONICS LTD.
TM
TM
TN100 System Installation and Troubleshooting
MT-3 Radio Systems
Daniels radio systems are designed for operation in highly varied conditions. Your application may
require high performance radio systems (intermod and selectivity) for operation in congested radio sites,
or operation over wide temperatures using battery solar powered systems (low current drain). A synthe-
sized radio may be appropriate for your emergency communications systems, or a crystal radio may be
needed for your data application. Daniels manufactures a diverse range of radio products tailored to the
type of operation you need.
The MT-3 radio system is characterized by high performance and reliability, whether it is a remote, low
current repeater or a high performance base station. The total system is designed to provide dependable,
low maintenance performance and great flexibility for expansion and servicing.
The MT-3 series of radio and control modules are packaged in the compact Eurostandard housing with
anodized aluminum front panels, and are ruggedly designed for remote or transportable applications. All
of the modules use high reliability components and corrosion resistant fasteners.
The MT-3 radio system is specifically designed to deliver high performance under adverse conditions.
Voltage stress testing and a 24 hour burn-in is performed on the radio system and performance of the sys-
tem at room temperature (25°°C) is documented and measured. As an option, extensive environmental
testing can be conducted over the temperature range - 40 °°C to + 60 °°C and the performance measured to
ensure compliance with the design specifications.
A Daniels MT-3 radio system consists of seperate RF receiver and transmitter modules plugged into a
standard 19” subrack. Each subrack also requires a control card and system monitor. External connec-
tions to the system (COR, PTT, audio, channel select, etc.) are made through an auxiliary connector on
the rear of the subrack. An optional cable or terminal strip connector is available to connect externally
through the auxiliary connector to the radio system. Most internal connections and control functions
(audio routing, COR - PTT, CTCSS, hang timers) are controlled by the audio control card. Contact the
factory for more information on the many custom configurations possible.
General Overview
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TECHNICAL NOTES
TN100 Rev 3-0-0 Sep 08 © Copyright 2008 Daniels Electronics Ltd. All rights reserved.
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DANIELS
DANIELS
ELECTRONICS LTD.
ELECTRONICS LTD.
TM
TM
TN100 System Installation and Troubleshooting
MT-3 Radio Systems
MT-3 Subrack
1. Ensure that the MT-3 Application Specific Manual is included with your system. This manual con-
tains information specific to the configuration of the radio system. It includes test sheets for each trans-
mitter, receiver and power amplifier, audio control card jumper lists, detailed instruction sheets for
CTCSS and DTMF modules if purchased, and other specific information. Each custom sheet should
have an Application number (Axxxx-xx) associated with that custom jumper setting, wiring, etc., as well
as a Block diagram (Bxxxx-xx). Please use this number in any future orders for identical systems.
NOTE: If ordered as a system, instruction manuals for each module (subrack, system monitor, receiver,
transmitter, etc.) are typically included with the equipment.
2. Ensure the main rack has enough room for the Daniels subrack to be installed. Each Daniels subrack
requires 5 1/4” height (3 RU) and 13.5” (maximum) depth clearances.
3. Install the EIA standard 19" subrack units in main rack using four #10 x 3/4" screws. Use stainless
steel screws if the equipment is to be placed in a corrosive environment. If necessary, remove the han-
dles from the subrack to facilitate installation.
4. Interconnect primary power (10 - 16 Vdc, 13.8 Vdc nominal) to the Barrier Strip power input on the
rear of the subrack (refer to drawing below). Use a wire gauge suitable for delivering the power required
by the subrack(s).
Installation and Set-Up
+
+
++
+
+
+
+
+
+
C89
R84
C88
R83
R85
C86
C87
JU45
JU46
JU47
JU48
JU49
JU50
JU51
JU52
JU53
JU54
JU55
JU56
JU57
JU58
JU59
JU60
JU61
JU62
JU63
JU64
JU65
JU66
JU67
JU68
R97
Q4 JU70
C98
C102
R90
R94
R89
C99
R88
R91
C100
R86 R87
R93
R81
R80
R82
R92
C82 C83
R95
R96
CR35
Q3
CR38
JU73
C94
C95
C96
C101
C93
C80
C81
FIL2
FIL1
C92
JU71
A
B
CR36
Q2
U86
U81
U83
U84
U85
C103
R98
R99
R100
R101
R102
C97
JU79
JU78
BC807-25
5k11
10k0
100nF
10µF
10k0
100nF
22k6
10k0
100nF
220pF
MC33172
100k
100k
10k0
MC14066BD
10k0
22µF
22µF
22µF
22µF
ICL232BE
MC14066BD
100R
604R
56R2
10k0
BAS16
MJD112
BC807-25
MBZ5233B
18K2
1K00
10µF 10µF
LP2951CM
4.7µF
10nF
100nF
1µF 100nF
1µF
100nF
274R
100nF
1R00
10R0
BYD17J
10k0
10k0
10k0
10k0
10k0
10nF
+
C85
+
+
1
5
1234
OPEN
FUSE F1
J8
CR1
CR2
SYSTEM
MONITOR
J6
ALARM
MODULE
J7
C7
C8
RFC2
C1C2C3
JU40 13.8 V
CR31
CR32
CR33
CR34
R15
R16
R17
R18
110
J68
TRZ1
TRZ2
RX B
J5
JU44 JU43
J20
RX A AUDIO
JU1 RX A 9.5 V
C4
C5 C6
JU36 JU37 JU38 JU39
TX B
J4
CR11 CR12 CR13 CR14
CR15 CR16 CR17 CR18
JU9
JU10 JU11 JU12
JU3 JU4 JU5 JU6
JU13 JU14 JU15 JU16
JU18 JU19 JU20 JU21
CR23
CR24
CR25
CR26
R7
R8
R9
R10
CR6
JU32 JU33 JU34 JU35
C10
RX A
J3
TX A
J2
M3
CONTROL
P1
CONTROL
MODULE
J1
RFC1
CR3 CR4 CR5
CR7 CR8 CR9
CR10
CR19
CR20
CR21
CR22
R3
R4
R5
R6
JU24 JU25 JU26 JU27
JU42 JU41
JU28 JU29 JU30 JU31
C9
J21
RX A AUDIO
JU 2 RX A 9.5 V
JU8
JU7
14 1
J67
J9
J72
J73
+
U82
C84
110
J74
JU69
U80
123
C90
C91
CR27
CR28
CR29
CR30
R11
R12
R13
R14
JU72
CR37
JU81 JU80
B A B A
D B Z D B Z D B Z D B Z D B Z
1N6378
1N6375
MR751
MR751
100nF
10nF
1nF
100nF 10nF
REMOTE INTERFACE
100nF
10nF
1nF
100nF
10nF
100K
100K
100K
100K
100K
100K
100K
100K
100K
100K
100K
100K
100K
100K
100K
100K
SYNTHESIZER
PROGRAMMER
INTERFACE
10mF
220µF
1mF
LM383
100µF
xxxxxx
gg
POWER INPUT
10 - 17 Vdc
+13.8 NOMINAL
JU17 J22
JU22 JU23
AMPL AUDIO
9.5 VDC IN / OUT
TX A RELAY
J57
J58
J59
J60
J61
J62
J63
J64
PTT
JU8
AB
WITH
TIME
OUT
NO
TIME
OUT
J32
J33
J34
TX A SYNTH
J16 No.1
J17 No.2
J48 J66
J41
J42
J43
J44
J45
J46
J18 J19
ISO COR
J12 J13
TX BAL I/P
J10
J11
RX BAL O/P
J35
J36
J37
J38
J39
J40
RX B
RELAY
J21
RX A AUDIO
JU 2 RX A 9.5 V
PTT-
COR MON
RX MUTE-
COR MON
TX STANDBY
TYPE 84 MOTHERBOARD 50016-02
DANIELS ELECTRONICS LTD
MADE IN CANADA
COR-
COR MON
MIC PTT-
COR MON
SYNTH PROG
RXA
TXA
RXB
TXB
TX A SUBTONE
INPUT
RX A I/O
SPARE
TX B
AUDIO
CNTL
B
A
RX A
CHANNEL
SELECT
B
A
J29
J30
J31
RX A SYNTH
TX B
AUDIO
CNTL
J65 J69 J70
TX A MIC
TO TX B
TX A MIC
TO TX B
RX A
RELAY
MIC PTT A-
MUTE RX A
TX B
CHANNEL
SELECT
B
A
J26
J27
J28
TX B SYNTH
J16 No.1
J17 No.2
J47
TX B SUBTONE
INPUT
RX B I/O
SPARE
PTT
JU7
AB
WITH
TIME
OUT
NO
TIME
OUT
TX A RELAY
J57
J58
J59
J60
J61
J62
J63
J64
R2
J49
J50
J51
J52
J53
J54
J55
J56
R1
TX B RELAY
RX B
CHANNEL SELECT
B
A
J23
J24
J25
RX B
SYNTH
RX B RX A
TX B TX A
RX B RX A
TX B TX A
J75
12
PWR FAIL
J71
1
3
TX A
CHANNEL
SELECT
SW1
TP2
TP1
15 AMP
FAST BLOW
FUSE
REVERSE
PROTECTION
DIODE
TRANSIENT
PROTECTION
9.5 Vdc
POWER OUTPUT AUXILIARY
CONTROL
CONNECTOR
5. If the subrack is using a DC - DC or AC Power Supply, refer to the specific manual supplied with the
equipment for installation instructions.
Page 2 of 9
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TECHNICAL NOTES
TN100 Rev 3-0-0 Sep 08
© Copyright 2008 Daniels Electronics Ltd. All rights reserved.
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DANIELS
DANIELS
ELECTRONICS LTD.
ELECTRONICS LTD.
TM
TM
TN100 System Installation and Troubleshooting
MT-3 Radio Systems
6. Interconnect +9.5 Vdc and +13.8 Vdc power between subrack units if one of the subracks does not
include a system monitor (no system monitor is required for a second subrack with only power ampli-
fiers mounted in it).
7. Install the modules in to the guide rail slots if not already configured. Adjust the guide rails for the
correct module positions if required (see the SR-3 subrack instruction manual). When installing mod-
ules, ensure the quick release fasteners on the top and the bottom of the modules are in the unlocked (slot
should be horizontal) position before insertion to the guide rails. To lock the quick release fasteners, push
and turn the fastener 90 degrees with a flat screwdriver.
Note: MT-3 modules may be removed or inserted from the subrack while power is supplied without dam-
aging the equipment.
8. Subrack and module operation is dependent on a series of shunts and jumpers throughout the RF mod-
ules, control modules and subrack. Review the Application Specific manual, and the receiver, transmit-
ter and subrack manuals to confirm system operation.
9. If control of the radio system is handled by a third party controller, a terminal strip connector should
be connected to the P1 auxiliary connector on the rear of the subrack. All wiring should be made to this
screw-type terminal connector.
10. For some applications, a cable, not a terminal strip connector, is used to connect to the auxiliary con-
nector. The cable must be plugged into the P1 auxiliary connector on the rear of the subrack. Ensure
locking tabs on the connector are completely engaged.
Receiver and Transmitter Modules
1. Check the frequency label to confirm that the receiver or transmitter is set up to operate on the desired
channel.
2. Connect the RF cables and ensure they are firmly screwed on.
3. Operate the transmitter with a 50 Ωload and confirm the power output is at the desired level. Adjust
the internal RF power control (inside the transmitter) for the correct power level if required. This may
be required for your nominal supply voltage if it is not 13.8 Vdc.
Installation and Set-Up
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TECHNICAL NOTES
TN100 Rev 3-0-0 Sep 08 © Copyright 2008 Daniels Electronics Ltd. All rights reserved.
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DANIELS
DANIELS
ELECTRONICS LTD.
ELECTRONICS LTD.
TM
TM
TN100 System Installation and Troubleshooting
MT-3 Radio Systems
4. Operate the receiver and ensure the sensitivity, squelch and squelch hysteresis are set to the desired
levels. The point at which the squelch breaks is not necessarily the 12 dB SINAD sensitivity measure-
ment for the receiver. The receiver has an internally adjustable squelch hysteresis control. This control
allows a spread between the opening and closing of the squelch (i.e., the sensitivity of the receiver may
be -117 dBm for 12 dB SINAD, but the squelch control could be set to unsquelch at -114 dBm and
squelch at -120 dBm).
The hysteresis control, typically factory set to 6 dB, is located on the main receiver board. The purpose
of this control is to allow a mobile or hand held radio to access the repeater with a "good" RF signal. The
receiver will then hold the signal over the 6 dB range while the signal from the mobile or hand held radio
is varying over this 6 dB range. This prevents the mobile or hand held radio from intermittently access-
ing the repeater in a marginal coverage area. To measure for 12 dBm SINAD sensitivity, press and hold
the front panel squelch disable button while making the measurement. This opens the receiver for max-
imum sensitivity.
Daniels Power Amplifier Set-Up and Installation
1. Check the frequency label to confirm that the power amplifier is set up to operate at the desired fre-
quency.
2. Install the power amplifier in the transmitter and receiver A or transmitter and receiver B slots as
required. If the power amplifier is upgrading the power output of the radio system, ensure that the guide
rails for the power amplifier are installed properly.
3. Connect the RF cables and ensure they are firmly screwed on.
4. Apply power to the subrack while measuring the RF power output. The RF output should be approx-
imately 30 watts with a 13.8 Vdc supply voltage. If the power level must be changed adjust the exciter
level (internal potentiometer) for the desired RF output (20 to 30 watts).
5. The VHF power amplifier has an 8 amp internal fuse. The fuse rating may be exceeded if the power
amplifier is driven to levels of 40 to 50 watts output. Ensure the exciter output is set to the correct drive
level and the VHF power amplifier is correctly tuned.
6. If the power amplifier is upgrading the power output of the radio system, check that the power feed
to the subrack is able to handle the increased current.
7. Check that the exciter power output does not exceed the maximum power input to the amplifier. In
some case the exciter may need to be replaced with a lower power version. VHF amplifier maximum
power input is 4 Watts, and UHF maximum power input is 2 Watts.
Installation and Set-Up
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TECHNICAL NOTES
TN100 Rev 3-0-0 Sep 08
© Copyright 2008 Daniels Electronics Ltd. All rights reserved.
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DANIELS
DANIELS
ELECTRONICS LTD.
ELECTRONICS LTD.
TM
TM
TN100 System Installation and Troubleshooting
MT-3 Radio Systems
1.0 Motherboard
1.1 Modules Do Not Fit in Subrack
1. Check the guide rail positions (refer to the SR-3 subrack instruction manual). Relocate the guide rails
if required.
2. Check the connectors on the back of the module for bent pins. Carefully straighten any bent pins if
required.
1.2 No Supply Power
1. If a system monitor is part of the radio system, a quick check for power is to turn the audio switch to
either A or B. If the LED turns on, power is present.
2. Inspect all power connections for continuity, polarity, etc.
3. Check the fuse on the M-3 Motherboard and replace if necessary (standard 15 amp fast blow). If fuse
blows again go to section 1.3.
4. Check any fuses outside of the radio subrack(s) and replace if necessary. If fuse blows again go to
section 1.3.
5. Check the subrack power input (terminal strip J8) and any batteries and/or power supplies for correct
voltages. There should be +10 to +17 Vdc at the power input.
6. Measure the battery voltage at the system monitor if one is installed. Select the supply voltage func-
tion on the system monitor rotary switch and measure the voltage at the front panel test jacks. There
should be +10 to +17 Vdc at this point.
7. If a system monitor is part of the radio system, jumper JU40 is usually not installed. Power is then
routed through the system monitor. If the system monitor is not plugged in, the other modules will not
have power. Ensure the system monitor is installed correctly.
Operational Troubleshooting
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TECHNICAL NOTES
TN100 Rev 3-0-0 Sep 08 © Copyright 2008 Daniels Electronics Ltd. All rights reserved.
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DANIELS
DANIELS
ELECTRONICS LTD.
ELECTRONICS LTD.
TM
TM
TN100 System Installation and Troubleshooting
MT-3 Radio Systems
9. The system monitor has either a fuse (optional) or a fuse bypass jumper. Check the fuse if it is
installed (rear panel). If no fuse is installed, remove the system monitor and test pins B2 and B4 on the
rear of the monitor for continuity. There should be a connection between these pins to provide the power
link.
10. Most modules require +9.5 Vdc power (internally regulated at the system monitor) as well as +13.8
Vdc (nominal supply voltage). If the system monitor is not functioning properly, this voltage may not be
present. Check for +9.5 volts at the system monitor test jacks (select +9.5 Volts regulated). If +9.5 Vdc
is not present, the system monitor fuse is good and +13.8 Vdc is present then a problem with the system
monitor exists. Refer to the system monitor instruction manual for further information on troubleshoot-
ing.
1.3 M-3 Motherboard Fuse Keeps Blowing
1. If lightning has been reported in the area, check the transient protection diodes TRZ1 and TRZ2 on
the motherboard. Replace if they are shorted or damaged.
2. Check the supply voltage for reversed connections. If the supply voltage was reversed, correct the sit-
uation and replace the fuse.
3. If a power amplifier is part of the system check that its output is at 30 watts maximum. It is possible
to drive these units to an output of 50 watts. Under these conditions the fuse rating may be exceeded.
2.0 Transmitters
2.1 Low or No RF Output
1. Confirm all RF connectors are securely fastened.
2. Ensure the transmitter module(s) are fully plugged in to the subrack and the quick release fasteners
are in the locked position.
3. Check power supplies by measuring them at the system monitor (section 1.2, step 6). Ensure there is
no voltage drop across the DC power supply cables to the subrack when all transmitters are keyed (max-
imum current). Install heavier gauge wire if required.
4. If a power amplifier is installed, confirm the exciter level and the primary power are set for 30 watts
power out (nominal supply voltage at +13.8 Vdc).
Operational Troubleshooting
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TECHNICAL NOTES
TN100 Rev 3-0-0 Sep 08
© Copyright 2008 Daniels Electronics Ltd. All rights reserved.
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DANIELS
DANIELS
ELECTRONICS LTD.
ELECTRONICS LTD.
TM
TM
TN100 System Installation and Troubleshooting
MT-3 Radio Systems
5. If the VHF or UHF power amplifier O/T (Over Temperature) indicator is 'ON' this would indicate a
severe power amplifier failure (refer to the service manual).
6. The TX indicator on the power amplifier indicates RF power is present in the module at the input to
the low pass filter. If this LED is not on it may be due to:
a) Incorrect LED threshold setting (internal to the power amplifier).
b) Failed RF module. Check the supply current to the module (VHF requires approximately 5.5A, UHF
requires approximately 6.7 A).
c) Failed RF cable connector.
d) Failed antenna system.
e) Failed or incorrectly tuned duplexer or multi-coupler
Note 1: Be sure to consider connector, cable and Duplexer losses when measuring the RF power.
Note 2: The normal RF power levels are set at the factory with a nominal supply voltage of 13.8 Vdc.
RF power will vary from +1 to -3 dB if your supply voltage is at the extreme higher or lower levels.
Note 3: Ensure the test equipment is calibrated correctly
2.2 Transmitter Modules Can Not Be Keyed by System
1. Ensure the transmitter module(s) are fully plugged in to the subrack and the quick release fasteners
are in the locked position.
2. Make sure the PTT jumpers are installed on the MT-3 motherboard selecting PTT With Time Out
(WTO) or PTT With No Time Out (NTO). Refer to the SR-3 subrack instruction manual for jumper
options and locations.
3. Check the PTT system configuration on the audio control card.
3.0 Receivers
3.1 Receiver Squelch Does Not Break at 12 dB SINAD
1. The point at which the squelch breaks is not necessarily the 12 dB SINAD point. The receiver mod-
ules have an internally adjustable squelch hysteresis control. Refer to the receiver instruction manual for
more information on this control.
Operational Troubleshooting
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TECHNICAL NOTES
TN100 Rev 3-0-0 Sep 08 © Copyright 2008 Daniels Electronics Ltd. All rights reserved.
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DANIELS
DANIELS
ELECTRONICS LTD.
ELECTRONICS LTD.
TM
TM
TN100 System Installation and Troubleshooting
MT-3 Radio Systems
3.2 Receiver Has No Squelch Tail
1. The receive and transmit repeat is very fast. To create a squelch tail the transmitter PTT uses a hang
timer to keep the transmitter keyed a moment longer after the input Tx key signal is removed. The hang
timer circuitry is located on the audio contro cardl. Ensure that the hang timer is enabled and the hang
timer adjustment potentiometer is set to an appropriate length of time. Refer to the audio control card
manual for more information on this control.
3.3 Receiver(s) are Noisy and Exhibit Poor Sensitivity
1. Check the battery charging circuits and/or the power sources to determine that the DC charging cir-
cuits are not noisy. Try removing the battery charge source, then re-test the receiver. Repair or replace
the charger if defective.
2. Examine all RF connectors thoroughly. Pull on the RF cables slightly and listen for any changes in
the receivers performance. Check that the center pin of the RF connector is correctly mounted (captive
center pin RF connectors should be used).
3. Check the duplexer alignment if the transmitter appears to de-sense the receiver module.
4. Review the installation area for any "data" or "clock" sources that may be causing harmful interfer-
ence.
4.0 System Monitor
4.1 +9.5 Vdc Switching On and Off
1. Depending on the hysteresis settings in the SM-3 (factory standard is 8 Volts shut-off, 11 Volts turn-
on - see system monitor instruction manual for different settings), the hysteresis circuits can oscillate if
a battery cell fails (opens) and the subrack is in the receive mode. In the receive mode, the current drain
is low and the "open" battery may still deliver the current required by the receiver circuitry. If the trans-
mitter is activated when a receive signal is present (normal repeat), the battery may drop below the SM-
3 hysteresis cutoff point, shutting the power (+9.5 Vdc) to the other subrack modules off, and reducing
the load to the batteries. When the load is reduced, the battery voltage will increase and turn on the SM-
3 hysteresis circuit. This condition causes the subrack modules to turn on and off which will not dam-
age the radios but does indicate a serious failure in the battery system.
Operational Troubleshooting
Page 8 of 9
43 Erie Street Toll Free Canada & U.S.A. International Internet
Victoria, B.C. Phone: [phone] Phone: [phone] e-mail: [email protected]
Canada V8V 1P8 Fax: [phone] Fax: [phone] web: www.danelec.com
TECHNICAL NOTES
TN100 Rev 3-0-0 Sep 08
© Copyright 2008 Daniels Electronics Ltd. All rights reserved.
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DANIELS
DANIELS
ELECTRONICS LTD.
ELECTRONICS LTD.
TM
TM
TN100 System Installation and Troubleshooting
MT-3 Radio Systems
5.0 Audio Control Cards
5.1 Deviation Between Receiver and Transmitter are Incorrect
1. Check the receiver output level using the extender card and note the impedance, either 600 Ωor 5 KΩ
(refer to the MT-3 Application Specific Manual).
2. Check the transmitter input level using the extender card, and note the impedance, either 600 Ωor
5 KΩ.
3. Reset the audio level on the audio control card for the desired system deviation operation.
5.2 CTCSS Operation Incorrect
1. Check that the front panel switch is in the 'ON' position for CTCSS operation.
2. Encode / decode module can be selected for encode only, decode only or both. Check that the desired
operation is selected (refer to the MT-3 Application Specific Manual).
3. The encode / decode frequency may be wrong. Use the DIP switches to select the correct frequency
for encoding and decoding the same tone. To encode a tone different from the decoder a separate CTCSS
module is used. Set this low current module using solder jumpers.
4. If a sub-audible tone appears on the repeat audio path check that the subtone filter on the audio con-
trol card is enabled or the receiver has its optional sub-tone filter installed.
Operational Troubleshooting
Page 9 of 9
43 Erie Street Toll Free Canada & U.S.A. International Internet
Victoria, B.C. Phone: [phone] Phone: [phone] e-mail: [email protected]
Canada V8V 1P8 Fax: [phone] Fax: [phone] web: www.danelec.com
TECHNICAL NOTES
TN100 Rev 3-0-0 Sep 08 © Copyright 2008 Daniels Electronics Ltd. All rights reserved.
TThhiisspprroodduucctthhaassbbeeeennddiissccoonnttiinnuueeddaannddiissnnoolloonnggeerrmmaannuuffaaccttuurreeddbbyyDDaanniieellssEElleeccttrroonniiccssLLttdd..