CES SDI-50 Troubleshooting guide

MODEL SDI-50
TELEPHONE INTERCONNECT
USER/SERVICE MANUAL
Communications Electronics Specialties, Inc.
931-218 S. Semoran BIvd.
Winter Park, FL 32792 USA
[phone]
[phone]
REV. 1/92
01000719
$20.00 (U.S.)

C.E.S. Model SDI-50 Manual
Table of Contents
1.0 TECHNICAL SPECIFICATIONS ................................... 1
2.0 MODEL SDI-50 GENERAL DESCRIPTION ........................... 3
2.1 FEATURES: ................................................ 3
3.0 SYSTEM OPERATION ........................................... 5
3.1 INITIATING A MOBILE TO LAND LINE CALL .................... 5
3.2 LAND LINE TO MOBILE CALL WITH AUTO-ANSWER ................ 5
3.3 LAND LINE TO MOBILE CALL WITHOUT AUTO-ANSWER ............. 5
3.4 INITIATING A DIAL-UP REMOTE CALL ......................... 5
4.0 INSTALLATION ............................................... 7
4.1 TERMINAL BLOCK CONNECTIONS................................ 7
4.1.1 TBl-1,15,23 and 25 GROUND .............................. 7
4.1.2 TB1-13 +VDC ............................................ 7
4.1.3 TB1-22 RELAY PTT OUTPUT ................................ 7
4.1.4 TB1-20 LOGIC PTT ....................................... 8
4.1.5 TB1-14 TRANSMIT AUDIO .................................. 8
4.1.6 TB1-4 AUXILIARY TRANSMIT AUDIO IN ...................... 8
4.1.7 TBl-9,10 and 21 AUXILIARY RELAY CONTACTS ............... 8
4.1.8 TB1-3 CTCSS-DCS DECODE INPUT ........................... 8
4.1.9 TB1-24 RECEIVER DISCRIMINATOR AUDIO .................... 9
4.1.10 TB1-6 and 19 CONTROL OUTPUTS ......................... 10
4.1.11 TB1-17 and 18 FUNCTION OUTPUTS 1 & 2 ................. 10
4.2 TELEPHONE LINE CONNECTIONS .............................. 11
4.3 OPTIONAL CTCSS DECODER .................................. 11
4.3.1 CTCSS FREOUENCY SELECTION TABLE ................... 12
4.4 SDI-50 JUMPER SUMMARY TABLE ............................. 13
5.0 LEVEL ADJUSTMENTS ......................................... 15
5.1 NOISE CONTROL R91 ....................................... 15
5.2 RECEIVE AUDIO LEVEL R60 ................................. 15
5.3 TRANSMIT VOICE LEVEL R75 ................................ 16
5.4 HYBRID BALANCE R40 ...................................... 16
5.5 TONE OUTPUT LEVEL R68 ................................... 16
5.6 REPEAT AUDIO LEVEL R61 .................................. 17
5.7 VOX SENSITIVITY R99 ..................................... 17
6.0 PROGRAMMING THE MODEL SDI-50 .............................. 18
6.1 ENTERING THE PROGRAM MODE ............................... 18
6.2 SPECIFIC PROGRAMMING APPLICATIONS ....................... 19
6.2.1 SIMPLEX SAMPLING PROGRAMMING PROCEDURE ................ 20
6.2.2 HALF/FULL DUPLEX PROGRAMMING PROCEDURE ................ 20
6.3 PROGRAM SUMMARY TABLE ................................... 21
6.4 TIMERS .................................................. 22
6.4.1 Sample Rate (*1 0) .................................... 23
6.4.2 Sample Window (*1 1) .................................. 23
6.4.3 Repeater Time-Out Timer (*1 2) ........................ 23
6.4.4 Repeater PTT Hang Time (*1 3) ......................... 23
6.4.5 Cali Limit Timer (*1 4) ............................... 24
6.4.6 Mobile Activity Timer (*1 5) .......................... 24
6.4.7 Station Identification Interval (*1 6) ................ 24
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C.E.S. Model SDI-50 Manual
6.5 SOFTWARE SWITCHES ......................................... 25
6.5.1 Toll Restrictions (*5 00 through *5 11) ............... 25
6.5.2 Selective Signalling (*5 12) .......................... 26
6.5.3 "*" Reset of The Cali Limit Timer (*5 13) ............. 27
6.5.4 Simplex Enable (*5 14) ................................ 27
6.5.5 Toll Restrict On The Ist Dialed digit (*5 15) ......... 27
6.5.6 Toll Restrict On The 2nd Dialed digit (*5 16) ......... 27
6.5.7 Tone To Pulse Dialing (*5 17) ......................... 28
6.5.8 Toll Restriction Override (*5 20) ..................... 28
6.5.9 Single digit "*" Connect Code (*5 21) ................. 28
6.5.10 Single digit "#" Disconnect (*5 22) .................. 28
6.5.11 Sample Rafe Multiplier (*5 23, 24) ................... 29
6.5.12 Repeat Enable (*5 23) ................................ 29
6.5.13 Courtesy Beep (*5 24) ................................ 30
6.5.14 Ring Counter (*5 25,26) .............................. 30
6.5.15 Interconnect Enable (*5 27) .......................... 30
6.5.16 Mobile Signalling Wait Time (*5 30,31) ............... 30
6.5.17 Ring Out (*5 32) ..................................... 31
6.5.18 Toll Restrict Enable (*5 33) ......................... 31
6.5.19 Automatic CW ID (*5 34) .............................. 32
6.5.20 Auto Answer (*5 35) .................................. 32
6.5.21 Half/Full Dúplex Enable (*5 36) ...................... 32
6.5.22 Repeat Enable (*5 37) ................................ 32
6.5.23 Mute on Pulse Dialing (*5 40) ........................ 33
6.5.24 Begin Outdial with Star (*) (*5 41) .................. 33
6.5.25 Begin Outdial with Pound (#) (*5 42) ................. 33
6.5.26 Phone in Use (*5 44) ................................. 34
6.5.27 DTMF Regenérate (*5 47) .............................. 34
6.6 CONTROL CODES ............................................. 34
6.6.1 Remote Programming Code (*6) .......................... 34
6.6.2 Connect and Disconnect Codes (*7 0) ................... 34
6.6.3 Special Connect Code (*7 1) ........................... 35
6.6.4 Functions (*7 2,3) .................................... 35
6.6.5 Interconnect Enable (*7 4) ............................ 36
6.6.6 Repeater Enable (*7 5) ................................ 36
6.6.7 Dial-up Remote Code (*8) .............................. 36
6.7 MESSAGES .................................................. 36
6.7.1 MESSAGE PROGRAMMING TABLE ............................. 38
7.0 OPERATING THE SDI-50 AS A REPEATER CONTROLLER ............. 39
7.1 INSTALLATION AND SET UP ................................. 39
8.0 SDI-50 PROGRAMMING LOG .................................... 40
9.0 MODEL SDI-50 CIRCUIT DESCRIPTION .......................... 42
9.1 GENERAL DESCRIPTION ..................................... 42
9.1.1 Microcomputer Control System .......................... 42
9.1.2 Customer Programmable Memory .......................... 42
9.1.3 DTMF Encoding and Decoding ............................ 42
9.1.4 Power Supply .......................................... 42
9.1.5 Power on Reset ........................................ 42
9.1.6 Watch Dog Timer ....................................... 43
9.1.7 Telephone Line Circuit ................................ 43
9.1.8 VOX Detect Circuit .................................... 43
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C.E.S. Model SDI-50 Manual
9.1.9 Noise Circuit ....................................... 43
9.1.10 CTCSS Level Comparator ............................... 44
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C.E.S. Model SDI-50 Manual
TECHNICAL SPECIFICATIONS
Physical:
Dimensions: 8.25" W X 1.5" H X 9.5" D
Weight: 3 Ibs., 13 oz.
Mounting: Table top or 19" rack mount
Electrical:
Voltage: 10 to 15 Vdc
Current: 250 mA
Memory: EEprom w/100 years memory retention
DTMF Error: -.54% to +.74% max
Transceiver:
Ground Keying: Source 100 mA @ .03 Vdc
Input from receiver: 50 mVrms to 2 Vrms, adjustable
Output to transmitter: O to 1.0 Vrms max., adjustable
Telephone:
Input from telco: -30 db to +2 db, 600 Ohm balanced
Output to telco: -10 db to +2 db, 600 Ohm balanced
Ring detect: Telco standard 90 Vac at 20 Hz
Hybrid isolation: -30 db mínimum
Indicators:
Front Panel:
Power
PTT
Connect
COR/CTCSS
Board Mount:
DTMF Strobe Detect
Front Panel Controls:
Power
Manual Connect/Disconnect
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C.E.S. Model SDI-50 Manual
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C.E.S. Model SDI-50 Manual
MODEL SDI-50 GENERAL DESCRIPTION
The CES Model SDI-50 Programmable Interconnect is a fully automatic
microprocessor controlled telephone interconnect for use in
land/mobile radio systems. The Model SDI-50 is designed as an
interface controller between the Public Switched Telephone Network and
land/mobile radio base station equipment. This interface allows
mobile radios to originate and receive telephone calis from the Public
Switched Telephone Network when the mobile is equipped with a standard
DTMF encoder for interconnect control. The CES Model SDI-50 is
capable of operating fuli dúplex, half dúplex or simplex.
2.1 FEATURES:
* Remotely programmable from any DTMF telephone for convenience.
* Single "*" and "^" connect and disconnect codes for simplicity.
* Programmable multi-digit connect and disconnect codes for system
security.
* Regenerated DTMF or pulse dialing into the telephone
network.
* Intelligent, prograinmable toll restriction suitable to your
application.
* Programmable call limit and mobile activity timers to help control
system loading.
* Time out warning signals before automatic disconnection.
* Morse code station identifier.
* Busy channel transmit lock out.
* Múltiple relay contad closures for custom applications.
* Repeater controller capability with programmable transmitter hang
time and time out timer makes the SDI-50 an inexpensive back-up unit.
* Regenerated DTMF land line to mobile selectivo signaling for
confidence in any network.
* Dial-up remote dispatch for simplex or repeater applications
eliminates costiy DC or tone remotes.
The Model SDI-50 is programmed by DTMF tones from any DTMF telephone
for "remote" programming, or by the DTMF encoder supplied with the
SDI-50 for "local" programming. Programming the Model SDI-50 allows
the unit to be customized to suit the particular requirements of your
interconnected system. All programming data is stored in an EEPROM
that maintains data integrity without power for a mínimum of 100
years.
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C.E.S. Model SDI-50 Manual
The Model SDI-50 is enclosed in an attractive cabinet with Mobile
Detect, Transmit, Connect and Power status LEDs mounted on the front
panel. Front panel Power and Connect/Disconnect switches provide for
local operator control.
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Model SDI-50 Manual, General Description
SYSTEM OPERATION
3.1 INITIATING A MOBILE TO LAND LINE CALL
A mobile to land line call can be initiated by using the following
sequence of operations:
¾A global Connect Code is an access code used by all users of
the system. Key the proper global Connect Code; "*" plus two
programmable numbers, or a single "*".
¾Unkey the transmitter and listen for a dial tone.
¾After dial tone is received, dial the desired phone number.
¾When the call is complete, dial the appropriate Disconnect
Code, which is a single "#"; or "#" plus two programmable
numbers.
3.2 LAND LINE TO MOBILE CALL WITH AUTO-ANSWER
This is a form of selectivo calling and requires the mobiles to be
equipped with a DTMF decoder. Dial the phone number of the line
connected to the CES Model SDI-50. If the channel is busy, the
interconnect will answer and give a series of three long beep tones;
then disconnect the calling party. If the channel is not busy, the
interconnect will answer on the programmed ring and return a single,
beep tone to the phone line. The caller shouid then enter the number
of the desired mobile; 1 to 5 DTMF digits terminated by a "#". The
interconnect will regenerate this number out to the mobiles as DTMF.
The mobile must answer with a "*", followed by the same number that
was dialed from the phone line. After the communication is completed,
the call may be terminated with the global disconnect from the mobile
or the phone line. If the mobile does not answer the call, the call
will be automatically terminated after the programmed wait period.
3.3 LAND LINE TO MOBILE CALL WITHOUT AUTQ-ANSWER
Dial the phone number of the line connected to the CES Model SDI-50.
The interconnect will detect the ring voltage on the phone line, key
the transmitter, and send the message programmed into the Error
Message area. The caller will hear the normal ring from the phone
company until a mobile answers the call. Any mobile may answer by
sending the global Connect Code. The call may be terminated from
either the phone line or the mobile after the call is completed by
sending the proper Disconnect Code.
3.4 INITIATING A DIAL-UP REMOTE CALL
This feature gives the caller dispatch capability and is available
whenever the SDI-50 is set up to automatically answer
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C.E.S. Model SDI-50 Manual, General Description
an incoming call. Dial the phone number of the line connected to the
CES Model SDI-50. The interconnect will answer on the programmed ring
and return a quick double "beep" tone to the phone line. The caller
shouid enter the Dial-Up Remote Code followed by a "#" tone and
proceed as a normal dispatch call. Anything said into the phone will
be transmitted to the mobiles, and all mobile traffic will be passed
to the caller. If the channel is busy at the time the caller enters
the Dial-Up Remote Code, the interconnect will return three long tones
and disconnect. After communications are complete, the call may be
terminated with the global disconnect code from the mobile or the
phone line.
Example: To initiate a Dial-up Remote call using Dial-Up Remote
Code "8421"; dial the interconnect phone number. When the
interconnect answers, dial "8421^". At this time the
interconnect will key the transmitter and transmit any audio
present on the phone line. There will be no tone to the caller
to indícate that the unit is transmitting. The caller should
remember that on simplex systems there will be a delay of up to
1 second (or the length of time of the programmed Sample Rate)
before the mobile can capture the interconnect, and talk after
the person on the phone finishes speaking.
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Model SDI-50 Manual, General Description
INSTALLATION
This section describes each connection required by the Model SDI-50
Interconnect. This section aiso describes optional jumpers on the
circuit board that can be used to customize the Model SDI-50 to your
particular transmitter-receiver combination.
Installation of the Model SDI-50 shouid be done by a qualified two-way
radio technician. Since the electrical components used are
susceptible to static damage, be sure to use static protection
techniques during the installation and level adjusting procedures.
During the installation, be sure that no power is applied to the
interconnect or radio.
Shielded cable shouid be used for all audio connections. To prevent
hum and noise due to ground loops, termínate the cable shield only at
the interconnect ground at the terminal block. The other end of the
shield must be left unconnected. Other connections to the Model SDI-
50 can be made using standard hook-up wire with sufficient current
rating. The best location for the interconnect is as close as
possible to the radio, thus allowing the shielded cables and wires to
be as short as possible.
4.1 TERMINAL BLOCK CONNECTIONS
Use the following instructions to make all connections to the terminal
block:
4.1.1 TBl-1,15,23 and 25 GROUND
These connection points are the main ground for the interconnect.
The GROUND connections, and chassis are common. Ground should be
connected directly to the "Common Ground Return" at the DC power
suppiy.
4.1.2 TB1-13 +VDC
This connection supplies DC power to the interconnect. This
connection shouid be made DIRECTLY to the +12 VDC power suppiy that
powers the radio equipment. If this is not available, any
regulated +12 VDC source with a current rating of at least 500 mA
may be used.
4.1.3 TB1-22 RELAY PTT OUTPUT
This connection is used for controlling the transmit function in
the associated transmitter. The PTT output shouid be connected to
the PTT line on the transmitter. As shipped from the factory, the
PTT output will próvido a relay contad pull to ground to key the
transmitter. If a pull to positive voltage is required to key the
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C.E.S. Model SDI-50 Manual, General Description
transmitter, then move JMP7 on the interconnect circuit board (near
the PTT relay K2), to position A.
4.1.4 TB1-20 LOGIC PTT
Logic PTT is similar to the relay PTT output except that it only
provides a ground to key the transmitter. Using this PTT control will
free the auxiliary relay contacts for user defined custom
applications.
4.1.5 TB1-14 TRANSMIT AUDIO
This connection supplies the transmitter with processed audio from the
telephone line. This connection shouid be made to the transmitter
microphone voice audio input. The TRANSMIT AUDIO is normally shipped
from the factory for a low impedance audio output. If the voice audio
input to your transmitter is high impedance, then remove JMP5 on the
interconnect circuit board to convert the TRANSMIT AUDIO output to
high impedance, and to match your transmitter impedance more closely.
This will permit the level adjustment to be less sensitivo. Be sure
to use shielded cable.
4.1.6 TB1-4_______AUXILIARY TRANSMIT AUDIO IN
This input is an auxiliary transmit audio input which can be used for
special applications when more then one audio source is needed or
used. There are no controls or level adjustments associated with this
input.
4.1.7 TBl-9,10 and 21 AUXILIARY RELAY CONTACTS
TB1-21 Relay Common
TB1-10 Relay Normally Closed (NC)
TB1-9 Relay Normally Open (NO)
These spare relay contacts are active when the interconnect keys the
PTT line or follows the phone line connect relay. The contact
arrangement can be used for switching logic signals, or audio signals.
The most common use for these contacts is to allow the interconnect to
switch between "Interconnect Transmit Audio" and "Repeat Transmit
Audio" that is derived from a repeater panel connected in the system.
JMP8
Auxiliary Relay Control________________________________Position
Auxiliary Relay follows the Connect Relay B/C
Auxiliary Relay follows the PTT signal B/A
4.1.8 TB1-3 CTCSS-DCS DECODE INPUT
This connection is optional, and can be left unconnected if not used.
The purpose of the CTCSS-DCS DECODE INPUT is to inhibit the
interconnect unless the proper CTCSS tone or Digital Coded Sgueich
(DCS) is present. Typically, this input is connected to an external
CTCSS decoder which, upon decode, will cause the CTCSS DECODE INPUT to
change state,
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C.E.S. Model SDI-50 Manual, General Description
and thus permit access to the interconnect. This type of connection
denies access and control to the interconnect if a mobile station does
not have the proper CTCSS tone. If CTCSS or DCS isn't used, place
JMP6 in D/A.
First, determine your CTCSS decoder's output signal when it detects
the proper CTCSS tone. Jumper 6 shouid be in one of the two following
positions for CTCSS use:
> Jumper JMP6 shouid be in position D/B if the CTCSS decoder’s
output is normally high (or high impedance) and goes to ground in
the presence of a valid tone.
Note: If the CTCSS decoder's output is open collector, a suitable
value pull-up resistor shouid be installed between E3 and E4 on
the SDI-50 PC board.
> Jumper JMP6 shouid be in position D/C if the CTCSS
decoder'soutput is normally low and goes to a positive voltage in
the presence of the proper tone.
The COR/CTCSS LED on the front panel should light each time the proper
CTCSS or DCS tone is transmitted.
Some decoders may only provide a small voltage change when detecting
the proper tone. Resistor R45 enables the installer to set the
reference of the voltage comparator to the midpoint between the high
and low signals from the CTCSS decoder. Set the voltage at pin 2 of
U17 to the midpoint by adjusting R45.
Example: D.C. voltage from decoder with no CTCSS = .7v
D.C. voltage from decoder with CTCSS = 1.9v
1.9V - .7V = 1.2V (output change)
1.2V / 2 = .6V (midpoint of change)
•7V (low end) + .6 (midpoint) = 1.3V
Set the voltage at pin 2 of U17 to 1.3v and place JMP6 in D/C since
this output goes positive with tone.
4.1.9 TB1-24 RECEIVER DISCRIMINATOR AUDIO
This connection supplies unfiltered discriminator audio from the
receiver to the interconnect for processing. THIS CONNECTION MUST BE
MADE DIRECTLY TO THE DISCRIMINATOR OUTPUT IN THE ASSOCIATED RECEIVER.
Because the SDI-50 has its own internal squeich circuits, and needs to
detect carrier for proper operation, do not connect the RECEIVER
DISCRIMINATOR AUDIO line after any de-emphasis circuits, or any
squeich circuits. Improper operation of the interconnect will result.
Be sure to use shielded cable with the shield terminated at the
interconnect's ground.
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C.E.S. Model SDI-50 Manual, General Description
Radios with external discriminator outputs usually do not provide raw
discriminator audio and signals taken from this location may not
function on the SDI-50.
Jumper JMP6 should in placed in position D/A unless CTCSS or DCS is
being used. If so, see the CTCSS section 4.1.8. for propper placement
of JMP6.
4.1.10 TB1-6 and 19 CONTROL OUTPUTS
TB1-19 Control Out 1 - CTRL 1
TB1-6 Control Out 2 - CTRL 2
These outputs are the open collectors of transistors Q22 and Q23.
These outputs are controlled by the Special Connect code. Either of
these outputs may be used for a customer defined purpose, i.e.,
remotely controlling other equipment.
TB1-19 CTRL 1 goes low true after receipt of the
Special Connect code and returns high automatically after
receipt of next disconnect code.
TB1-6 CTRL 2 goes low true after receipt of Special Connect
code followed by the connect code. Returns high after receipt
of next disconnect code. Temporary Toll Defeat (*5 20) must be
on for CTRL 2 to work.
These codos are not available during the time the patch is temporarily
disabled by code "*7 4".
4.1.11 TB1-17 and 18 FUNCTION OUTPUTS 1 & 2
TB1-17 Function 2 Output
TB1-18 Function 1 Output
These outputs are for user defined applications to control or switch
other equipment or relays.
Both are the open collectors of transistors Q20 and Q21 and might need
to be pulled to +5V or +12V depending on the intended use. These
outputs are able to sink up to 500mAdc continuously. When the
interconnect is first powered up, Function 1 is in the "ON" state, and
Function 2 is in the "OFF" state.
Both outputs are turned on and off by sending the user defined
Function On/Off Codes (*7 2 and *7 3). See the section on programming
for the use of these codes. They may still be used while the patch is
temporarily disabled from code "*74".
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C.E.S. Model SDI-50 Manual, General Description
4.2 TELEPHONE LINE CONNECTIONS
The Model SDI-50 interfaces directly with a "loop start" telephone
line. Connection to the telephone line is accomplished by plugging
the modular telephone cord supplied with the interconnect into your
telephone company supplied RJ11-C jack. Please note that the
telephone line interface on the interconnect is not polarity
sensitive, and therefore the Tip and Ring connections can be reversed
without any system degradation.
4.3 OPTIONAL CTCSS DECODER
Space has been set aside for the addition of a CTCSS decoder. The
installation list below is for the C.E.S. Model 5732 CTCSS high speed
decoder (although most CTCSS decoders will work without any problem).
Connect the five wires and set the 5732 for the proper CTCSS tone
according to the Frequency Selection Table. See the Jumper Summary
Table in the next section to configure JP6, and follow any operating
instructions sent with the 5732 decoder.
CTCSS is useful for two different applications. The first is for
access security, and the second for an alternative carrier detect
signal.
For access security, connect the decoder as shown below. To use the
decoder as carrier detect, connect it as below but omit the DISABLE
(E12) connection.
5732 WIRE________________IN SDI-50
Decode output (yellow) E8
Tone Input (green) E9
+12 Vdc (red) E10
Ground (black) Ell
Disable (orange) E12
Add a 27K resistor between E3 & E4
All connection points can be found in the upper, left hand corner of
the printed circuit board.
Use the table on the next page to set the switches for the desired
tone.
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C.E.S. Model SDI-50 Manual, General Description
4.3.1 CTCSS FREQUENCY SELECTION TABLE
SWITCH # SWITCH #
No FREQ CODE 5 4 3 2 1 No FREQ CODE 5 4 3 2 1
1 67.0 XZ 0 0 0 0 0 17 118.8 2B 1 0 0 0 0
2 71.9 XA 0 0 0 0 1 18 123.0 3Z 1 0 0 0 1
3 74.4 WA 0 0 0 1 0 19 127.3 3A 1 0 0 1 0
4 77.0 XB 0 0 0 1 1 20 131.8 3B 1 0 0 1 1
5 79.7 SP 0 0 1 0 0 21 136.5 4Z 1 0 1 0 0
6 82.5 YZ 0 0 1 0 1 22 141.3 4A 1 0 1 0 1
7 85.4 YA 0 0 1 1 0 23 146.2 4B 1 0 1 1 0
8 88.5 YB 0 0 1 1 1 24 151.4 5Z 1 0 1 1 1
9 91.5 ZZ 0 1 0 0 0 25 156.7 5A 1 1 0 0 0
10 94.8 ZA 0 1 0 0 1 26 162.2 5B 1 1 0 0 1
11 97.4 ZB 0 1 0 1 0 27 167.9 6Z 1 1 0 1 0
12 100.0 1Z 0 1 0 1 1 28 173.8 6A 1 1 0 1 1
13 103.5 1A 0 1 1 0 0 29 179.9 6B 1 1 1 0 0
14 107.2 1B 0 1 1 0 1 30 186.2 7Z 1 1 1 0 1
15 110.9 2Z 0 1 1 1 0 31 192.8 7A 1 1 1 1 0
16 114.8 2A 0 1 1 1 1 32 203.5 M1 1 1 1 1 1
1= switch turned on 0= switch turned off
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C.E.S. Model SDI-50 Manual, General Description
4.4 SDI-50 JUMPER SUMMARY TABLE
Jumper Jumper
Number Name
JMP1 Phone in Use Detect
Intact: the SDI-50 checks the phone line for a busy
condition before allowing a mobile to connect, but, still
allows the use of the Special Connect Code for selective
override. (See Special Connect Code. )
Cut: a mobile may break into land-line to land-line
communication if the interconnect shares a common line with
a telephone.
JMP2 Receive Audio
Intact: This provides a fíat frequency response from the
receiver to the telephone line.
Cut: If the receive audio pick-up point is after de-
emphisis, cut this juinper.
JMP3 Modified Pulse Dialing
Intact: Make Break ratio = 40/60 at lOpps
Cut: Make to Break ratio = 44/56 at 10 pps
JMP4 Transmit Control
Intact: Half dúplex operation.
Cut: Full dúplex and Simplex operation.
JMP5 Tx Level
Intact: Low impedance output of Tx amp.
Cut: High impedance output of Tx amp.
JMP6 Mobile Detect
The center pin, D, is common and connects to one of the
three other pins; A, B and C.
Pin A: Selects Noise only as the mobile detect signal.
Pin B: Selects CTCSS/DCS as the mobile detect signal for a
HIGH to LOW change when the mobile keys.
Pin C: Selects CTCSS/DCS as the mobile detect signal for a
LOW to HIGH change when the mobile keys.
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C.E.S. Model SDI-50 Manual, General Description
JMP7 Relay PTT Level
The center pin, B, is common and connects to one oí the
other two pins; A or C.
Pin A: Relay PTT provides +12Vdc to key the transmitter.
Pin C: Relay PTT provides a ground to key the transmitter.
JMP8 Aux. Relay Control
The center pin, B, is common and connects to one of two
pins; A or C.
Pin A: The auxiliary relay follows the keying of the
transmitter to connect and disconnect.
Pin C: The auxiliary relay follows the phone line connect
relay for control.
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C.E.S. Model SDI-50 Manual, Level Adjustments
LEVEL ADJUSTMENTS
Now that all connections have been made to the Model SDI-50, the next
step is to perform all level adjustments required for proper operation
in your system. An FM service monitor, an oscilloscope, or AC RMS
voltmeter, and the DTMF encoder provided with the SDI-50 are required
for level adjustments.
The numbers in parentheses show the location on the assembly drawing
the pots can be found.
5.1 NOISE CONTROL R91
(5,C) The noise control is used for muting the audio (squeich noise),
when no carrier exists on the radio channel. This condition is
indicated by the MOBILE DETECT LED on the front panel of the Model
SDI-50. When the LED is illuminated, this indicates that the SDI-50
detects carrier. When it´s extinguished, no carrier is detected.
Jumper JMP6 shouLd be in position D/A if carrier alone is used to
detect mobile presence. If a CTCSS or DCS decoder is going to be
used, see the CTCSS section in this manual for other JMP6
configurations.
To adjust the Noise Control, use a small alignment tool to rotate R91.
Start from a fully counter-clockwise position and note that the Mobile
Detect LED on the front panel is "On". Turn R91 clockwise until the
LED turns "Off". Continue rotating the adjustments about 1/8 of a
turn further. Please note that the Noise Control can be turned even
further clockwise to inhibit very weak and noisy signals from
accessing the interconnect. Use your own judgement as to the quality
of transmissions from mobile stations required to use your system. If
you can not adjust R91 so that the LED extinguishes, then re-check the
Receiver Discriminator Audio connection in the Installation Section
and re-check JMP6 for proper placement.
5.2 RECEIVE AUDIO LEVEL R60
(5,D) The RX AUDIO LEVEL controls the signal level from the radio
receiver to the telephone line and DTMF level to DTMF decoder. To
adjust the RX AUDIO LEVEL, set your service monitor to genérate an 800
Hz. audio signal at 4.0 Khz. deviation on the receive frequency of
your system. Connect an oscilloscope or AC RMS voltmeter to pin 7 of
U16. Push the Connect switch on the front panel of the SDI-50, and
carefully adjust the RX AUDIO LEVEL adjustment, R60, for a 3.0 volt
peak to peak reading sine wave (1.0 Vrms). Adjusting R60 beyond this
level will result in a distorted and clipped signal. If
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C.E.S. Model SDI-50 Manual, Level Adjustments
a sufficient level can't be obtained, cut JMP2 to increase the gain of
the receive amp U13 and re-try. This completes the RX VOICE LEVEL
adjustment.
5.3 TRANSMIT VOICE LEVEL R75
(6,C) This adjustment is used to set the signal level from the
telephone line to the radio transmitter. To adjust the TRANSMIT VOICE
LEVEL, adjust your service monitor to listen to the output frequency
of the transmitter. Adjust the Transmit Voice Level, R75, to 4.0 Khz
deviation. If you encounter difficulty setting this level because the
potentiometer is overly sensitive then remove JMP5.
5.4 HYBRID BALANCE R40
(5,B) The Hybrid Balance adjustment is used in "full duplex" systems
only (where mobile stations are capable of receiving and transmitting
simultaneously). If your system is "half duplex" or simplex, (where a
mobile can only transmit, or receive at a given time), then this
adjustment may not be required. This adjustment cannot be made unless
the interconnect is programmed for "full duplex" operation.
The hybrid balance adjustment should be performed on the phone line
which the interconnect is to be used on. Durring adjustment, the SDI-
50 will have to be in the Connect Mode on a quiet line. To achieve
this, call into the interconnect and answer the call by pushing the
Connect button. Or, call time and temperature, and wait for the
recording to stop.
Set your service monitor to generate an 800 Hz. audio signal at 4.0
kHz deviation on the receive frequency of your system, allowing the
signal to pass through the hybrid circuit and back out through the
TRANSMIT AUDIO OUTPUT. The calling party will also hear this tone.
Now while watching the deviation level of the signal generated by the
Model SDI-50, adjust the HYBRID BALANCE adjustment, R40, for a minimum
signal in the deviation level. This adjustment is critical, and if a
sharp null is not found by turning the HYBRID BALANCE through a
complete rotation, then an additional compensation capacitor may be
required to match the telephone line impedance. Install a value from
.047uf to .47uf in the location for C28, near the HYBRID BALANCE
adjustment. After this capacitor is installed, try again to adjust
the HYBRID BALANCE for a null. If the null is still not satisfactory
then repeat this capacitor substitution process until until an
acceptable null is achieved.
5.5 TONE OUTPUT LEVEL R68
(6,C) Set your service monitor to receive on your transmit frequency.
Dial the phone number of the telephone line connected to the SDI-50.
After the SDI-50 answers and returns
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