CES SDI-50 User & Service Manual

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

Page # i

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

Page # ii

C.E.S. Model SDI-50 Manual

9.1.9 Noise Circuit ....................................... 43

9.1.10 CTCSS Level Comparator ............................... 44

Page # iii

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

Page # 1

C.E.S. Model SDI-50 Manual

This page left blank

Page # 2

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.

Page # 3

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.

Page # 4

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:

¾ A 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 "*".

¾ Unkey the transmitter and listen for a dial tone.
¾ After dial tone is received, dial the desired phone number.
¾ When 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

Page # 5

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.

Page # 6

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 SDI­50 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

Page # 7

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,

Page # 8

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.

Page # 9

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".

Page # 10

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.

Page # 11

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

Page # 12

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 de­emphisis, 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.

Page # 13

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.

Page # 14

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

Page # 15

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 SDI­50 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

Page # 16

C.E.S. Model SDI-50 Manual, Level Adjustments

a tone to the telephone line, overdial a 5 digit DTMF number
terminated with the #.

Note: the program switches "*5 12" and "*5 35" must be on. If
this is a first time installation, they would have been turned
on at the factory. If this is a re-installation, review the

section on programming to set these switches on.
Set R68 to 3.0 - 3.5 kHz. peak deviation on the regenerated tones.
This level adjustment sets the level for the Morse code ID messages as

well as the level of the DTMF tones. At any particular setting the
DTMF tones will be twice the level of the ID messages. Therefore it
is important to use DTMF tones for setting the level, and not the ID
tones.

5.6

REPEAT AUDIO LEVEL R61
(5,C) If the Repeat function is to be used, it must be adjusted after
programming.

Generate a signal on the receive frequency modulated by an 800 hz tone
at 4.0 kHz deviation. Adjust R61 to 4 kHz deviation on the
transmitter frequency.

5.7

VOX SENSITIVITY R99
(5,C) For simplex mode only. To adjust the VOX Sensitivity, the SDI­50 must be programmed for the simplex mode. First set R99 fully
counter clockwise. Call the SDI-50 from a land line; answer the call
and speak into the telephone in a normal voice. Monitor the DC
voltage at pin 7 of U19 while adjusting R99 in a clockwise direction.
Advance R99 until the voltage at pin 7 goes low with voice audio and
returns high with no audio.

An easy way to make this adjustment is to call (from the mobile or
handheid) a local recording such as Time and Temperature. While
listening to the message turn R99 clockwise until you hear the sample
rate change.

Before going on to program the CES SDI-50, you must have properly
completed the previous installation section and have the interconnect
connected to the radio and telephone line.

Page # 17

C.E.S. Model SDI-50 Manual, Level Adjustments

PROGRAMMING THE MODEL SDI-50

It is not necessary to program every parameter in the Model SDI-50 to
get your interconnect properly set up and tested. In that interest two
short programming procedures are listed for simplex and half/full
duplex operation in the section which follows. It is suggested that
you select and follow the appropriate required procedures for your
application, then review the factory default values for optional
program changes. Detailed instructions for the programming parameters
can be found in the next section.

The SDI-50 can be programmed remotely through the telephone line or
locally through the front panel with the use of the handheld DTMF
encoder provided. In either case, the programming sequence is
identical, and only the method by which programming access is obtained
differs.

The Program Summary Table lists all of the programmable features of
the Model SDI-50 interconnect. All of the features have factory
programmed values which are listed in the center column.

6.1

ENTERING THE PROGRAM MODE
The program mode may be entered in one of two ways:

Local Programming Mode - With the supplied DTMF tone pad plugged
into the front of the interconnect, dial "O", then press the
connect button on the SDI-50 within five seconds. The SDI-50
will respond with a beep tone indicating that it is in the
programming mode. (In order to hear response tones when locally
programming the SDI-50, you will need to have a service monitor
or receiver tuned to the transmit frequency).

NOTE: Because the SDI-50 is constantly monitoring receive
audio for DTMF tones, it is possible that DTMF tones
received from Rx audio may interfere with programming in
the local programming mode. If the receiver is turned on,
temporarily remove jumper JMP6 during programming to keep
the SDI-50 from recognizing these tones.

Remote Programming Mode - The SDI-50 must have Auto Answer
enabled to use this feature. Dial the telephone number of the
line connected to the interconnect. When the interconnect
answers, it will send two quick beep tones to the phone line.
Enter the Remote Programming Code followed by a "#". If the
correct code is entered, the SDI-50 will

Page #18

C.E.S. Model SDI-50 Manual, Level Adjustments

send a single, quick, beep tone to indícate it is in the Program
Mode. If the wrong code is entered, the SDI-50 will disconnect.
The SDI-50 must be set for Auto Answer to have remote
programming capability.

Enter the Program Codes according to the following instructions:

¾ Once a programming sequence is started (by entering a "*"),

an inter-digit timer starts running and is reset each time
another digit is entered. Time out is set to be within six
seconds between digits for all programming enfries except the
messages, which are ten seconds between digits.

¾ To change any of the programmable features simply re-program

the new values or codes over the existing ones. It is not
necessary to "clear" the location of old data first.

¾ Any of the programmable features may be changed without

reprogramming all of the others. Some of the codes may
require specific switches to be set, or work in conjunction
with other codes. These requirements are identifed
throughout the manual where ever applicable.

¾ When changing modes (i.e. Simplex to 1/2 Duplex) make certain

than any commands pertaining to control functions in the
exited mode are turned off.

¾ The programming codes are grouped by their functions. All

codes start with the "*" key and follow a similar format;
each of which is described in it's code group section.

¾ The examples in this manual show when the SDI-50 sends

response tones to acknowledge receipt of DTMF tones, and help
guide the entry of the program commands.

Exit the Programming Mode by sending a "#" tone. Some Control Codes
that allow variable code lengths (*6 & *8) use the "#” to indícate the
end of the code "string". This is expected in these programming
sequences, and will merely terminate the sequence but will not exit
you form the programming mode.

If the interconnect is being programmed remotely, it will
automatically disconnect and terminate the programming mode if no DTMF
tones are detected for one full minute. Thus, if you were to hang up
before sending the "#" tone, the interconnect will revert to normal
operating mode one minute after the last DTMF tone was sent.

6.2

SPECIFIC PROGRAMMING APPLICATIONS
The following section has required and optional programming for

specific applications. Refer to the corresponding section in this
manual for the use and function of the following program codes if you
are not yet familiar with them. In the lists below, the "?" shouid be
replaced with actual digits at the time of programming, to suit the
particular needs and

Page # 19

C.E.S. Model SDI-50 Manual, Level Adjustments

timing of your system. The Program Summary Table lists the factory
setting for these codes as well as the page specific information for
each may be found.

6.2.1

SIMPLEX SAMPLING PROGRAMMING PROCEDURE
To use the SDI-50 in the simplex sampling mode, the following changes

to the factory set-up need to be made. Any change made should be
penciled into the Program Log in the back of this manual for future
reference.

Required Programming for Simplex Operation

> Turn on Simplex Enable (*5 14) *5 14 1
> Turn off Half/Full Duplex Enable (*5 36) *5 36 O
> Set the Sample Rafe (*1 0) *1 O ?
> Set the Sample Rate Multiplier (*5 23, 24) *5 23 ?

*5 24 ?
> Set the Sample Window (*1 1) *1 1 ?

> Turn off the Repeat Enable (*5 37) *5 37 O
> JMP4 shouid be cut or removed.

6.2.2

HALF/FULL DUPLEX PROGRAMMING PROCEDURE
To use the SDI-50 in either duplex mode, the following changes to the

factory set-up need to be made. Any change made should be penciled
into the Program Log in the back of this manual for future reference.

Required Programming for Dúplex Operation

> Turn off Simplex Enable (*5 14) *5 14 O
> Turn on Half/Full Duplex Enable (*5 36) *5 36 1
> Turn on Repeat Enable (*5 37) *5 37 1
> Set the Repeater Time-Out Timer (*1 2) *1 2 ?
> Set the Repeater PTT Hang Time (*1 3) *1 3 ?
> JMP4 shouid be cut or removed if full duplex.

? = User option

> JMP4 should be intact for half duplex.

Page # 20

C.E.S. Model SDI-50 Manual, Level Adjustments

6.3

PROGRAM SUMMARY TABLE

PROGRAM FACTORY SEC
CODE DESCRIPTION SETTING No.

*1 TIMERS 6.4
0 Sample Rate (Simplex) 1 sec.22 6.4.1
1 Sample Window (Simplex) 60 ms. 6.4.2
2 Repeater Timer Out Timer (Duplex) 7 min. 6.4.3
3 Repeater Hang Time (Duplex) 2 ms. 6.4.4
4 Call Limit Timer 3 min. 6.4.5
5 Mobile Activity Timer 20 sec. 6.4.6
6 I.D. Interval Timer 10 min. 6.4.7
*5 SOFTWARE SWITCHES 6.5
00 Toll restrict on number 7 off 6.5.1
01 Toll restrict on number 6 off
02 Toll restrict on number 5 off
03 Toll restrict on number 4 off
04 Toll restrict on number 3 off
05 Toll restrict on number 2 off
06 Toll restrict on number 1 on
07 Toll restrict on number 0 on
10 Toll restrict on number 8 off V
11 Toll restrict on number 9 off 6.5.1
12 Selective Signaling on 6.5.2
13 “*” Call Limit Reset on 6.5.3
14 Simplex enable (note 1) (simplex) off 6.5.4
15 Toll restrict on 1st digit (note 2) on 6.5.5
16 Toll restrict on 2nd digit on 6.5.6
17 Pulse dialing off 6.5.7
20 Toll Restriction Override on 6.5.8
21 Single digit “*” connect off 6.5.9
22 Single digit “#” disconnect on 6.5.10
23 2X Sample Rate (note 2) (Simplex) off 6.5.11
24 4X Sample Rate (Simplex) off 6.5.11
23 Repeat enable (note 1) (Duplex) on 6.5.12
24 Courtesy Beep Enable (Duplex) off 6.5.13
25 Answer on 1,2,4 or 8 rings (note 2) on 6.5.14
26 Used Together With #25. off 6.5.14
27 Interconnect enable on 6.5.15
30 Mobile Signalling Wait Time (note 2) on 6.5.16
31 Used Together With Code #30 off 6.5.16
32 Ringout enable on 6.5.17
33 Toll restrict on 6.5.18
34 Auto I.D. on 6.5.19
35 Auto answer on 6.5.20
36 Half/Full Duplex Enable on 6.5.21
37 Repeat Enable on 6.5.22
40 Mute on Pulse Dial on 6.5.23
41 Begin Overdial with “*” off 6.5.24
42 Begin Overdial with “#” off 6.5.25
44 Phone Line In Use Detect on 6.5.27
47 DTMF Regenerate on 6.5.28

Page # 21

C.E.S. Model SDI-50 Manual, Level Adjustments

PROGRAM FACTORY SEC
CODE DESCRIPTION SETTING No.

*6 Remote programming code 975310# 6.6.1
*7 Control Codes
0 Connect/Disconnect Codes *73/#73 6.6.2
1 Special Connect Code *37 6.6.3

ON OFF
2 Control Function #1 Code *14 *04 6.6.4
3 Control Function #2 Code *25 *15 6.6.4
4 Interconnect Enable Code *36 *26 6.6.5
5 Repeat Enable Code *38 *28 6.6.6
*8 Dial-up Remote Code 8421# 6.6.7
*9 Messages 6.7
0 Connect Message “ON”
1 Disconnect Message “OFF”
2 Time out Message “TO”
3 Error/Signal/Message “EEEEEEEE” V
4 Station I.D. Message “RING” 6.7

Note I - For repeater operation, *5 23 shouid be turned on and *5 14

shouid be turned off. When *5 14 is on, the patch is in
simplex mode and *5 23, and *5 24 are used to modify the sample
rate.

Note 2 - This is a two part switch. The following switch number must

also be set. Refer to the section in the manual for more
detail on setting these.

Note 3 - Switches 23 and 24 have different uses for simplex and duplex

operation. If switch 14 is on and 36 is off, then 23 and 24
are used to adjust the sample rafe for simplex use. If 14 is
off, and 36 is on, then 23 is used for "Repeat Enable" and 24
is for "Courtesy Beep" during duplex use.

6.4

TIMERS

Several timers are available to configure the interconnect for optimum
use or persional preference. All timers are set with the *1 code.
The format to program these is:

*1 N T T T
| | |____ Three digits must be entered to specify the length of

| | time. Leading zeros are used for numbers smaller than
| | three digits long.

| |__________ This is a one digit number to identify which timer is
| being changed.

|______________ All timer codes start with *1.

Page # 22

C.E.S. Model SDI-50 Manual, Level Adjustments

6.4.1

Sample Rate______(*1 0)
For simplex operation oniy. The sample rate is the rate at which the
interconnect unkeys the transmitter and checks for mobile activity.
This value should be set to your liking, keeping in mind that the
mobile cannot "capture" the interconnect until a sample window occurs,
and may be modified by codes *5 23 and *5 24. This function is
programmed in 0.1 second steps by entering a three digit multiplier.

Example: If you wished to set this value at 1.5 seconds
enter the following sequence:

*1 (tone) O (tone) 015 (tone)

6.4.2

Sample Window (*1 1)
For simplex operation only. The sample window is the length of time
the transmitter is unkeyed allowing the receiver to determine the
presence of a mobile carrier. The sample window should be set as short
as possible while still allowing the mobile to capture the
interconnect on a weak signal. The function is programmed in 2 ms.
steps by entering a three digit multiplier.

Example: 010 wouid give 20ms (10 X 2ms = 20ms), and 100 wouid
give 200 ms. To set the sample window to lOOms. enter the
following:

* 1 (tone) 1 (tone) 050 (tone)

6.4.3

Repeater Time-Out Timer (*1 2)
For duplex operation only. This function is used to control the
repeater use time. Up to 4 minutes and 10 seconds can be used. This
function is programmed in 1 second steps by entering a 3 digit
multiplier.

Example: To set the time out for 3 minutes:

*1 (tone) 2 (tone) 180 (tone)

6.4.4

Repeater PTT Hang Time (*1 3)
For duplex operation only. The hang time is the amount of time the
repeater remains keyed after mobile carrier ceases. This function is
programmed in 0.1 second steps by entering a 3 digit multiplier.

Example: To set the PTT hang time to 3 seconds:

*1 (tone) 3 (tone) 030 (tone)

Page # 23

C.E.S. Model SDI-50 Manual, Level Adjustments

6.4.5

Cali Limit Timer (*1 4)
This timer controls the maximum duration of the interconnected call.
Time out will be preceded with double warning beeps once every two
seconds. The time out warning is sent 20 seconds before the actual
time out. After the interconnect has timed out the Time Out Message
is sent. The time out timer can be reset by the mobile operator if the
software switch *5-13 is turned on. This timer is programmed in 10
second steps up to a total of 21 minutes, by entering a 3 digit
multiplier.

Example: To program the Call Limit Timer to three minutes enter
the following sequence (18 X 10 seconds = 3 minutes):

*1 (tone) 4 (tone) 018 (tone)

6.4.6

Mobile Activity Timer (*1 5)
This timer is used to disconnect the interconnect and unkey the
transmitter if the mobile should drive out of rango, or go off the
air. Each time the mobile transmits, the Mobile Activity Timer is
reset. Actual time out is preceded with single warning tones, once
every two seconds for ten seconds prior to time out. This function is
programmed in 1 second steps up to a total of 4 minutes, by entering a
3 digit multiplier.

Example: Program the activity timer for 30 seconds:

*1 (tone) 5 (tone) 030 (tone)

6.4.7

Station Identification Interval (*1 6)
This Program Code determines how often the Station ID Message is
transmitted automatically; but if desired the call sign could be
programmed into any message location. The time is entered as multiples
of 10 seconds.

Example: To set the Station ID timer for 10 minutes:

*1 (tone) 6 (tone) 060 (tone)

Page # 24

C.E.S. Model SDI-50 Manual, Level Adjustments

6.5

SOFTWARE SWITCHES

The Programming Codes starting with "*5" are actually switches that
are turned on if the function is desired or off if the function is not
wanted. The format used is:

*5 NN X
| | |
| | |_____ "1" to turn the function on.

| | "O" to turn the function off.

| |_________ This is the two digit number which identifies

| the function switch.

|_______________ This is used for all function switch changes.

Check the examples for each of the following cedes.

6.5.1

Toll Restrictions (*5 00 through *5 11)
If you wish to restrict all users, except those who know the Special
Connect Code (*7 1) from making toll calls, then program these
restrictions. Attempted dialing of a toll restricted telephone number
will result in the Error Message being transmitted, and then immediate
disconnect.

For toll restriction to be active, software switch *5 33 should be
turned on.

To program the toll restrictions you first need to determine what
numerals dialed as either the first or second digit of a telephone
number would result in a toll call. In most areas of the United
States, toll calls start with the number "1". In areas where the area
code can be dialed, the second number of the area code will be a "O"
or a "1". The number "9" should also be considered for restriction
because there is usually a charge to call numbers starting with "900"
and "976".

When programming you will "Flag" these numerals as restricted
numerals. You then program the unit to check for these "flagged"
numerals in either the first, second, or both positions of the dialed
number (using switches 15 and 16). Use the table on the following
page to "Flag" the numerals.

Page # 25

C.E.S. Model SDI-50 Manual, Level Adjustments

NUMBERS TO BE RESTRICTED *5
____________

ON OFF_________
*5 06 1 O NUMBER 1
*5 05 1 O NUMBER 2
*5 04 1 O NUMBER 3
*5 03 1 O NUMBER 4
*5 02 1 O NUMBER 5
*5 01 1 O NUMBER 6
*5 00 1 O NUMBER 7
*5 10 1 O NUMBER 8
*5 11 1 O NUMBER 9
*5 07 1 O NUMBER O

Example: To have the numeral "1" toll restricted enter the following
sequence:

*5 (tone) 06 (tone) 1 (tone)

To have the numeral "9" restricted enter this sequence:

*5 (tone) 11 (tone) 1 (tone)

Restricted Digits (*5 15,16)
Numbers which were flagged by the switches 00 through 11 will be
restricted as the first dialed digit by using Program Code "*5 15".
Use Code "*5 16" for the second dialed digit.

Restrict Program
From__________________Sequence
First digit ON "*5 15 1"
First digit OFF "*5 15 O"

Second digit ON "*5 16 1"
Second digit OFF "*5 16 O"

Example: To restrict the "flagged" numerals from being the first

digit dialed, but allow it as the second, enter this sequence:

*5 (tone) 15 (tone) 1 (tone)
*5 (tone) 16 (tone) O (tone)

6.5.2

Selectivo Signalling (*5 12)
This Program Code Enables DTMF selective signalling to the
mobiles by "overdialing" a DTMF ANI code from the telephone.
Auto Answer (*5 35) must also be turned on for this to work.
The Ínterconnect will answer on the

Page #26

C.E.S. Model SDI-50 Manual, Level Adjustments

programmed number of rings that it's set for. When the caller hears
two short beeps the number of the mobile desired shouid be entered
followed with the "#". The "#" is used to terminate the mobile ANI
number and isn't sent out as part of the signalling.

If this switch is turned off, and Auto Answer is on, the interconnect
will still answer a call to allow remote programming, but won't allow
signalling.

( Aiso set *5 switchs 30, 31, 41 and 42 )

* 5 (tone) 12 (tone) 1 (tone) ;allow signalling

* 5 (tone) 12 (tone) O (tone) ;disallow signalling

6.5.3

"*" Reset of The Cali Limit Timer 1*5 13)
If turned on, this switch enables the mobile operator to reset the
Call Limit Timer by transmitting the "*" tone. If turned off, the
interconnect will time out after the time specified in the Call Limit
Timer (*1 4).

*5 (tone) 13 (tone) 1 (tone) ;allow reset
*5 (tone) 13 (tone) O (tone) ;disallow reset

6.5.4

Simplex Enable (*5 14)
This function enables the simplex use of the interconnect. If simplex
use is desired, turn this function on and turn *5 36 off. See section

6.2.1 for minimum requirements to enable the simplex mode.

* 5 (tone) 14 (tone) 1 (tone) ;enable simplex
* 5 (tone) 14 (tone) O (tone) ;disable simplex

6.5.5

Toll Restrict On The Ist Dialed digit (*5 15)
If the restricted numbers set by *5 00-11 are to apply to the first
dialed digit, then turn this switch on. If any number designated as a
restricted digit is dialed as the first digit of the phone number,
then the interconnect will disconnect and send the Error Message.

*5 (tone) 15 (tone) 1 (tone) ;restrict 1st digit
*5 (tone) 15 (tone) O (tone) ;don't restrict

6.5.6

Toll Restrict On The 2nd Dialed digit (*5 16)
If the restricted numbers set by *5 00-11 are to apply to the second
dialed digit, then turn this switch on. If any number designated as a
restricted digit is dialed as the second digit of the phone number,
then the interconnect will disconnect and send the Error Message.

Page # 27

C.E.S. Model SDI-50 Manual, Level Adjustments

*5 (tone) 16 (tone) 1 (tone) ;restrict 1st digit
*5 (tone) 16 (tone) O (tone) ;don't restrict

6.5.7

Tone To Pulse Dialing (*5 17)
This Program Code enables or disables tone to pulse dialing. Pulse
dialing would be used wherever the local telephone company does not
offer DTMF circuits to the interconnect location. Pulse Dialing can
also be used on DTMF circuits to increase the reliability of dialing
out from the mobile. If pulse dialing is used on a DTMF line, then
switch *5 40 should be turned on aiso to keep the central office from
detecting DTMF tones between pulses.

*5 (tone) 17 (tone) 1 (tone) ;Pulse Dialing
*5 (tone) 17 (tone) O (tone) ;DTMF Tone Dialing

6.5.8

Toll Restriction Override (*5 20)
This code allows the use of the Special Connect Code (*7 1) to defeat
toll restriction for one call. After the call, the programmed toll
restrictions are automatically rearmed. If this switch is turned off
the toll restrictions will apply to all calls. See the "Special
Connect Code" for details on it's use.

*5 (tone) 20 (tone) 1 (tone) ;allow toll defeat
*5 (tone) 20 (tone) O (tone) ;no toll calls

6.5.9

Single digit "*" Connect Code (*5 21)
This switch overrides the Connect Code so that it's only necessary to
transmit the "*" tone to access the interconnect. If this switch is
turned off, then "*" plus the two digits programmed into *7 O are used
to access the interconnect.

Note that using a single "*" for access to the interconnect, disables
the use of all the mobile controlled options programmed with *7.

To enable or disable the single "*" Connect Code this function is
turned on or off as follows:

*5 (tone) 21 (tone) 1 (tone) ;single "*" connect
*5 (tone) 21 (tone) O (tone) ;Connect Code required

6.5.10

Single digit "#" Disconnect (*5 22)
This switch overrides the Disconnect Code so that it's only necessary
to transmit the "#" tone to disconnect the interconnect. If this
switch is turned off, then "#" plus the two digits programmed into *7
O are used to disconnect

Page #28

Model SDI-50 Manual, Level Adjustments

the interconnect. To enable or disable the single "#" disconnect,
this function is turned on or off as follows:

* 5 (tone) 22 (tone) 1 (tone) ;single "#" disconnect
* 5 (tone) 22 (tone) O (tone) ;Disconnect Code

6.5.11

Sample Rate Multiplier (*5 23, 24)
Switches 23 and 24 have a dual function. See below for duplex use of
these switches.

When the SDI-50 is used in simplex mode, the VOX circuit monitors
telephone audio and modifies the sample rate to reduce the
interruptions in transmission and determine the optimum sample time.
When phone line audio ceases, the sample rate returns to the
programmed rate. On the initial connect, dial tone audio is ignored
and the sample rate will be at the programmed rate. After dialing,
the Model SDI-50 will begin responding to telephone line audio and
decreasing the sample rate.

The sample rate will automatically be slowed down to provide less
interruptions in the phone line audio. When turned on, switch 23 will
multiply the sample rate by two, switch 24 multiplies it by four, and
with both on, the rate is multiplied by eight.

23 24 _________ Change to Sample______
off off no sample rate change
on off rate change is X2
off on rate change is X4
on on rate change is X8

Example: The sample rate has been set to one sample per second and it
is desired that it be once every two seconds when phone line audio is
present. Enter the following:

*5(tone) 23(tone) l(tone) ;turn on X2
*5(tone) 24(tone) O(tone) ;turn off X4

6.5.12

Repeat Enable (*5 23)
For duplex use only. This switch allows receive audio to be repeated
for mobile to mobile communication. This is most useful when the SDI­50 is connected to two separate radios and used as a repeater.

*5 (tone) 23 (tone) 1 (tone) ;enable repeat audio
*5 (tone) 23 (tone) O (tone) ;disable repeat audio

Page #29

C.E.S. Model SDI-50 Manual, Level Adjustments

6.5.13

Courtesy Beep (*5 24)
When the SDI-50 is set up for Repeater Operation it can be programmed
to generate a "Courtesy Beep" one second after the end of each
transmission. This tone is useful for prompting the other party to
begin speaking. Program this function as follows:

*5 (tone) 24 (tone) 1 (tone) ;courtesy beep
*5 (tone) 24 (tone) O (tone) ;no courtesy beep

6.5.14

Ring Counter (*5 25,26)
When the interconnect is set to automaticly answer an inbound
telephone call, it will answer on the 1st, 2nd, 4th, or 8th ring by
setting these switches. Use the table that follows to set the ring
counter to the desired number of rings.

25 26 Ring Count
off off 1st ring
on off 2nd ring
off on 4th ring
on on 8th ring

Example: To answer on 2nd ring enter a "1" for switch *5 25; and a "O"
for switch *5 26.

*5 (tone) 25 (tone) 1 (tone)
*5 (tone) 26 (tone) O (tone)

6.5.15

Interconnect Enable (*5 27)
This enables or disables the interconnect function without affecting
the repeater control function (if used). With this switch turned off,
no interconnect calls are allowed. This differs from the function 7 4
in that it isn´t under mobile control for a temporary state.

*5 (tone) 27 (tone) 1 (tone) ;interconnect enabled
*5 (tone) 27 (tone) O (tone) ;interconnect disabled

6.5.16

Mobile Signalling Wait Time (*5 30,31)
When selectivo signalling is used to call a mobile, these switches set
the length of time the interconnect will wait for the mobile to answer
before disconnecting the land line.

30 31 Wait Time
off off 15 seconds
on off 30 seconds
off on 45 seconds
on on 60 seconds

Page #30

C.E.S. Model SDI-50 Manual, Level Adjustments

Example: To program a 30 second wait time enter a "1" and "O"
for switches 30, and 31.

*5 (tone) 30 (tone) 1 (tone)
*5 (tone) 31 (tone) O (tone)

6.5.17

Ring Out (*5 32)
When a landiine call comes into the interconnect, it will key the
transmitter and send out the Error/Signal Message to notify the
mobiles that a call is coming in. The ring-out will occur each time
the SDI-50 senses the ring voltage on the phone line, up to the point
that the interconnect answers if the Auto-Answer feature is on. The
Ring Count (switches *5 25 and *5 26) should aiso be set if Auto­Answer is used.

During the global ring out, any mobile may answer by using the global
Connect Code (switch *7 0). If no mobile answers before the
interconnect answers the call, selective signalling may still be done
as normal, if this feature is aiso turned on. However, only the
called mobile may answer.

Ring Out may be turned off if only selective signalling is desired, or
if its desired that the interconnect be dedicated to mobile to
landline calls.

For the interconnect to continuously ring out; until either a mobile
answers or the land line caller hangs up, Ring Out (switch *5 32) must
be turned on, and Auto Answer (switch *5 35) must be turned off.

For example: If Ring Out and Auto Answer are enabled, and switches 25
and 26 are set for 8 rings, the ringout will occur 7 times before the
SDI-50 answers.

*5 (tone) 32 (tone) 1 (tone) ;ring out enabled
*5 (tone) 32 (tone) O (tone) ;ring out disabled

6.5.18

Toll Restrict Enable (*5 33)
The toll restriction parameters are set using switches *5 00 through
11, 15 and 16. These switches only define the way toll restriction
will work. Switch 33 is used to actívate toll restriction. Toll
restriction may be temporarily turned off then back on with this
switch instead of changing all switches pertaining to toll restrict.

*5 (tone) 33 (tone) 1 (tone) ;toll restrict enabled
*5 (tone) 33 (tone) O (tone) ;toll restrict disabled

Page #31

Model SDI-50 Manual, Level Adjustments

6.5.19

Automatic CW ID (*5 34)
When Automatic CW ID is turned on, the interconnect will automatically
send the ID Message at programmed intervals only when the interconnect
sees activity. If the ID interval has elapsed, the SDI-50 will
automaticly send the ID message the next time it sees activity on the
channel. If this function is turned on, you must also program the
Station ID in the ID Message area (*9 4), and the ID Interval (*1 6).

*5 (tone) 34 (tone) 1 (tone) ;enable CW ID
*5 (tone) 34 (tone) O (tone) ;disable CW ID

6.5.20

Auto Answer (*5 35)
Auto Answer allows the interconnect to automatically answer an
incomming call from the phone. The Auto-Answer provides three
separate functions:

a. Land line to mobile selective signaling
b. Dial up remote control
c. Remote programming capability.

When auto answer is turned on, remote control and remote programming
are always active while selective signaling and Ring Out may be turned
on or off. If auto answer is off, then the interconnect will signal
the mobile and wait for the mobile to send the connect code before the
call is answered.

* 5 (tone) 35 (tone) 1 (tone) ;enable auto answer
* 5 (tone) 35 (tone) O (tone) ;disable auto answer

6.5.21

Half/Full Duplex Enable (*5 36)
For duplex operation. This function must be turned on for the SDI-50
to operate in a half or fuli duplex mode. Aiso see the minimum
programming requirements for duplex operation in section 6.2.2.

*5 (tone) 36 (tone) 1 (tone) ;duplex mode
*5 (tone) 36 (tone) O (tone) ;simplex mode

6.5.22

Repeat Enable (*5 37)
For duplex operation. This function provides PTT logic to the
transmitter whenever the SDI-50 detecte mobile carrier so that receive
audio is retransmitted. This function works independently of the
Interconnect Enable Code, and can be used to provide mobile to mobile
repeater service when the interconnect is disabled. Two timers are
also provided; PTT hang time (*1 3), and repeater time out (*1 2).
With this feature, two radios can be used as a

Page #32

C.E.S. Model SDI-50 Manual, Level Adjustments

repeater. The repeater function can be turned on or off from the
mobile with the Repeater Enable Code (*7 5).

*5 (tone) 37 (tone) 1 (tone) ;repeat path & PTT
*5 (tone) 37 (tone) O (tone) ;no repeat path

6.5.23

Mute on Pulse Dialing (*5 40)
This switch mutes receive audio into the phone line when the mobile
first originates a call. If the interconnect is going to be used in
the pulse dialing mode, then this switch may need to be turned on.
Some exchanges will accept both Tone or Pulse dialing. Allowing the
DTMF tone to be interrupted by the pulses will cause unreliable
dialing. The mobile´s carrier is monitored to determine when dialing
is completed and un-mute the Receive Audio.

*5 (tone) 40 (tone) 1 (tone) ;mute is enabled
*5 (tone) 4O (tone) O (tone) ;no muting

6.5.24

Begin Outdial with Star (*) (*5 41)
When selective signalling is used, some systems may require a "*" tone
to be sent before the mobile ID number. If this switch is turned on,
the SDI-50 will automatically inserí a "*" before the overdialed
mobile number.

*5 (tone) 41 (tone) 1 (tone) ;include a leading "*"
*5 (tone) 41 (tone) O (tone) ;number sent as dialed

6.5.25

Begin Outdial with Pound (#) (*5 42)
When selective signalling is used, some systems may require a "#" tone
to be sent before the mobile ID number. If this switch is turned on,
the SDI-50 will automatically insert a "#" before the overdialed
mobile number.

*5 (tone) 42 (tone) 1 (tone) ;include a leading "#"
*5 (tone) 42 (tone) O (tone) ;number sent as dialed

Page #33

C.E.S. Model SDI-50 Manual, Level Adjustments

6.5.26

Phone in Use (*5 44)
Normally the interconnect won't allow a mobile to break into an
existing phone conversation (with JMP1 in place). If the line is in
use, the mobile operator will receive the Error Message when access is
attempted. This switch will allow mobiles to brake into an existing
call on the phone line only if the Special Connect Code is sent along
with the normal Connect Code.

*5 (tone) 44 (tone) 1 (tone) ;allow access w/"SCC".
*5 (tone) 44 (tone) O (tone) ;Error if line is busy.

6.5.27

DTMF Regenerate (*5 47)
This switch causes DTMF regeneration into the phone line when the
mobile first originales a call. Often weak signais may not be
adequate for the central office to decode. The mobile's carrier is
monitored to determine when dialing is completed and regeneration
stops.

*5 (tone) 47 (tone) 1 (tone) ;DTMF regeneration
*5 (tone) 47 (tone) O (tone) ;no regeneration

6.6

CONTROL CODES

6.6.1 Remote Programming Code (*6)
When the Auto Answer function is on, the interconnect can be remotely
programmed from the telephone line by entering the Remote Programming
Code after the interconnect answers. This code can be 1 to 6 digits
in length. If you try to enter more than six digits, only the first
six will be recognized. Enter the desired digits for the code,
terminated by a "#". The "#" is not considered to be part of the
code, only a terminator when fewer than six digits are used for the
code. Also, the "#", in this case will not take you out of
programming mode. A second "#" is required to discontinue programming
mode if you wish to do so after changing the Remote Programming Code.

Example: To chango the remote programming code

to "56789":

*6 (tone) 5 6 7 8 9 # (tone)

6.6.2

Connect and Disconnect Codes (*7 0)
This code sets the global 2 digit Connect and Disconnect Code
used to access and disconnect the interconnect when selective
signalling is not used. This Program Code establishes two
numerals that must always follow the "*" sign to connect, and

Page #34

C.E.S. Model SDI-50 Manual, Level Adjustments

the "#" sign to disconnect (except when the single "*" or "#" is used

- *5 21,22).

Example: To use "*89" as the global connect code and "#89"
as the global disconnect code, enter:

*7 (tone) O (tone) 89 (tone)

6.6.3

Special Connect Code (*7 1)
This code has three features which modify the normal Connect Code sent
by the mobile. Each is explained in it´s own paragraph below. In all
cases, the Special Connect Code is sent directly in front of the
normal Connect Code. For example, using the factory settings for the
two codes, the mobile operator wouid send "*37 *73" to utilize a
Special Connect Code feature. Because the Special Connect Code starts
with a "*", it isn't available when the single tone "*" is used as the
normal Connect Code.

Toll Restriction Bypass - This code will allow users which know
the Special Connect Code to defeat the programmed toll
restrictions for one call only. Toll restriction is
automatically rearmed for the next call upon disconnect. To
enable Toll Restriction Defeat, switch *5 20 should be turned
on. If a toll call override isn't desired turn *5 20 off.

Phone Line In Use Detector - This code will allow a mobile
originated call to break into a call already in progress. This
could be the case when the interconnect shares a line with an
active phone. Switch *5 44 should be off if it is desired to
prevent mobiles from breaking into calls. To interrupt a call
in progress oniy when the Special Connect Code is sent, turn
switch *5 44 is on. Note that if jumper JMP1 is cut, all mobile
calls will break into a call in progress, even without the
Special Connect Code.

The Special Connect Code controls the two outputs "CTRL 1" and
"CTRL 2". See the section describing these outputs for more
information on them.

Program this exactly as the Connect Code in *7 0. To program 38 as
the Special Connect Code, enter:

*7 (tone) 1 (tone) 38 (tone)

6.6.4

Functions (*7 2,3)
The control Function outputs are available at the back connector TB1­17 and TB1-18. These Functions have no predetermined use in the SDI­50's normal operation and are provided for customized applications.
These Functions can be turned ON and OFF by DTMF command from the
mobile operator. To use these Control Function

Page # 35

C.E.S. Model SDI-50 Manual, Level Adjustments

outputs a line should be run to an external transistor for switching.
Since the function outputs pulse once per second, an electrolitic
capacitor of some value shouid be tied to the transistor bases, to
smooth the pulses.

Because the codos to control these functions require a leading "*",
they may not be used when the interconnect is set for "*" only
connect.

6.6.5

Interconnect Enable (*7 4)
This code is used in conjunction with Program Code *5 27. Code *5 27
configures the SDI-50 to be capable of interconnecting calls. This
Control Code enables the system operator to remotely turn the
interconnection capability On and Off from the telephone by using DTMF
tones.

6.6.6

Repeater Enable______(*7 5)
This code is used in conjunction with Program Code *5 23. Code *5 23
configures the interconnect to enable a repeat audio path when a
telephone call is not being processed. This Control Code enables the
system operator to to remotely turn the repeat capability On and Off
from a the telephone using DTMF tones.

6.6.7

Dial-up Remote Code (*8)
The Dial-Up-Remote feature is always active when auto answer is on.
There is a programmable Dial-up Remote Code that must be dialed after
auto answer beep to access the radio transmitter and receiver. After
entering this code, all phone audio is transmitted to the mobiles and
all received audio is passed into the phone. This code can. be 1 to 6
digits in length. If you try to enter more than 6 digits the first
six will be the Dial-up Remote Code.Enter the desired digits
terminated by a "#". The "#" is not counted as part of the Dial-up
Remote Code.

Example: To program a Dial-up Remote Code of 9654 enter the
following: *8 (tone) 9654# (tone)

MESSAGES

6.7
Five separate user programmable Morse Code Messages are available in

the CES SDI-50 to help establish the status of the interconnect.
These are:

Connect Message (*9 0) - This message is sent each time a
mobile operator sends the Connect Code to access the
interconnect, whether to answer an incomming call or to
originate a call.

Disconnect Message (*9 1) - This message is sent each time the
SDI-50 is disconnected by the mobile operator.

Page # 36

Model SDI-50 Manual, Level Adjustments

Time Out Message (*9 2) - The time out message is sent if the
Call Limit Timer or the Mobile Activity Timer has expired and
the SDI-50 originales the disconnect.

Error/Signal Message (*9 3) - The Error/Signal Message is sent
on two different occurrences:

> Signalling: It alerts the mobile operator of an incomming
land line call. The SDI-50 will send the Error Message each
time it detects ring voltage on the phone line. If the message
programmed into the Error Message area is longer than four or
five seconds in duration (the interval between rings), then the
message will be sent on every other ring detected.

> Error: This Message is used to indicate to the mobile
operator of an error in accessing the interconnect. For example,
this condition exists when a mobile operator tries to dial a
restricted phone number, or during programming if an invalid
program code is entered.

NOTE: Never remove the Error Message. This Message is essential
to inform the operator of several functions and error conditions
durring use and programming; thus, a programmed message shouid
always be present. It's characters may be changed, but do not
remove them all.

Station I.D. Message (*9 4) - The Station I.D. Message is sent
each time the Station Identification Interval Timer (*1 6) has
elapsed. It is only sent when carrier activity is seen on the
channel. If the I.D. timer times out durring a period of
inactivity, the I.D. message will be sent upon the next
occurrence of mobile activity.

All Messages are limited to eleven characters each and mustbe
terminated with a stop bit ("08"). If an Message is removed, a stop
bit ("08") must be entered in its place.

Example: To remove the Connect Message, enter *9

(tone) O (tone) O8 (tone)

Message's are programmed by selecting the two digit codes from the
"Message Programming Table" which represents the alpha numeric
characters used in the message.

Page # 37

C.E.S. Model SDI-50 Manual, Level Adjustments

The format for programming all messages is:

*9 N CC CC .... CC 08

| | \ / |
| | \ / |
| | \ / |__ All messages must end with
| | \ / "08".
| | \ /
| | V_____________ A two digit number is entered
| | to represent each character of
| | the message. *
| |
| |__________________________ One digit to identify the
| message being entered (0-4).
|
|________________________________ *9 is used to start each
message programmed.

* - A beep tone will be sent by the SDI-50 between each two digit
character number as they are entered.

Example: To program "OFF" in the disconnect Message enter the

following: *9 (tone) 1 (tone) 63 (tone) 33 (tone) 33
(tone) 08 (tone).

Remember, when progranuning the Message's not to forget the enter the
stop bit; "08"

6.7.1

MESSAGE PROGRAMMING TABLE

CHAR. CODE CHAR. CODE CHAR. CODE

0 00 I 43 A 37

1 10 J 51 A 38

2 20 K 52 E 39

3 30 L 53 U 47

4 40 M 61 N 44

5 50 N 62 O 45

6 60 O 63 CH 35

7 70 P 71 AR 07

8 80 Q 02 ERROR 48

9 90 R 72 , 16

A 21 S 73 - 66

B 22 T 81 . 46

C 23 U 82 / 36

D 31 V 83 ? 94

E 32 W 91 SP ERROR 96

F 33 X 92 SPACE 05

G 41 Y 93 STOP 08

H 42 Z 03

Page # 38

C.E.S. Model SDI-50 Manual, Repeater Controller

OPERATING THE SDI-50 AS A REPEATER CONTROLLER

The SDI-50 can be configured to function as a repeater controller when
wired to a full duplex base station, separate transmitter and
receiver, or an existing repeater. The SDI-50 will control the
transmitter with programmable hangtime and timeout functions. The
repeat audio path provides internal squelching, subaudible tone
filtering, automatic gain control, and courtesy tone if desired.
There is also a provision for CTCSS control. A programmable Morse
code station identifier is provided specifically for this mode. If a
telephone line is available, the interconnect or phone patch mode can
aiso be used to take full advantage of all features included with the
unit.

INSTALLATION AND SET UP

7.1
Installation as a repeater controller is essentially the same as with
the duplex installation. The main exception is that a single
transceiver generally can not be used. A transceiver that is capable
of fuli duplex operation, or has been modified to so that the
transmitter and receiver work independently of each other will usually
work. Two transceivers may be used by making the appropriate
connections to each.

Before adjustments can be made, all connections to the associated
radios must be complete, and the repeat mode enabled. See section

6.2.2 to enable the repeat mode. However, before enabling the repeat
mode you must make sure that the "Mobile Detect" LED is functioning
properly. This is critical to any operation of the SDI-50 if noise
squeich is to be used. Refer to the NOISE CONTROL level adjustment to
make any necessary changes to the Noise Control R91.

If CTCSS is desired, a connection to a sub audible tone decoder or
repeater tone panel will be necessary. See CTCSS control in section

4.1.8 for configuration of JMP6 and threshold adjustment. Once you
have made the adjustments and established that the front panel "Mobile
Detect" LED is functioning properiy (normally extinguished;
illuminated when a mobile is detected), programming changes and the
final adjustments can begin. There are some repeater mode parameters
to be programmed which shouid be set as in section 6.2.2.

There is one other audio level adjustment necessary for repeater
operation. This is the Repeat Audio Level; R61. Adjust the repeat
audio level as in the Level Adjustments in section 5.6.

Page # 39

Model SDI-50 Manual, Repeater Controller

SDI-50 PROGRAMMING LOG

PROGRAM FACTORY
CODE DESCRIPTION SETTING CHANGED TO

*1

TIMERS TIME

0 Sample Rate (Simplex) 1 sec. ___________
1 Sample Window (Simplex) 60 ms. ___________
2 Repeater Time Out Timer (Dúplex) 7 min. ___________
3 Repeater Hang Time (Dúplex) 2 ms. ___________
4 Call Limit Timer 3 min. ___________
5 Mobile Activity Timer 20 sec. ___________
6 I.D. Interval Timer 10 min. ___________

*5

SOFTWARE SWITCHES SETTING

00 Toll restrict on number 7 off ___________
01 Toll restrict on number 6 off ___________
02 Toll restrict on number 5 off ___________
03 Toll restrict on number 4 off ___________
04 Toll restrict on number 3 off ___________
05 Toll restrict on number 2 off ___________
06 Toll restrict on number 1 on ___________
07 Toll restrict on number O on ___________
10 Toll restrict on number 8 off ___________
11 Toll restrict on number 9 off ___________
12 Selectivo Signaling on ___________
13 "*" Call Limit Reset on ___________
14 Simplex enable (note 1) (simplex) off ___________
15 Toll restrict on 1st digit (note 2) on ___________
16 Toll restrict on 2nd digit on ___________
17 Pulse dialing off ___________
20 Toll Restriction Override on ___________
21 Single digit "*" connect off ___________
22 single digit "#" disconnect on ___________
23 2X Sample Rate (note 2) (Simplex) off ___________
24 4X Sample Rate (Simplex) off ___________
23 Repeat enable (note 1) (Duplex) on ___________
24 Courtesy Beep Enable (Duplex) off ___________
25 Answer on 1,2,4 or 8 rings (note 2) on ___________
26 Used Together With #25. off ___________
27 Interconnect enable on ___________
30 Mobile Signalling Wait Time (note 2) on ___________
31 Used Together With Code #30 off ___________
32 Ringout enable on ___________
33 Toll restrict on ___________
34 Auto I.D. on ___________
35 Auto answer off ___________
36 Half/Full Dúplex Enable on ___________
37 Repeat Enable on ___________

Page #40

Model SDI-50 Manual. Repeater Controller

*

PROGRAM
CODE DESCRIPTION FACTORY SETTING CHANGED TO

40 Mute on Pulse Dial on ___________
41 Begin Overdial w/"*" off ___________

42 Begin Overdial w/"#" off ___________
43 Phone in Use on ___________
47 DTMF Regenerate on ___________

*6
*7

Remote programming code 975310#

Control Codes

0 Connect/Disconnect Codes *73/#73 ___________
1 Special Connect Code *37 ___________

ON OFF
2 Control Function #1 Code *14 *04 ___________
3 Control Function #2 code *25 *15 ___________
4 Interconnect Enable Code *36 *26 ___________
5 Repeat Enable Code *38

*8
*9

Dial-up Remote Code 8421# ___________
Messages

28 ___________

0 Connect Message “ON” ___________
1 Disconnect Message “OFF” ___________
2 Time out Message “TO” ___________
3 Error/Signal Message “EEEEEEEE” ___________
4 Station I.D. Message “RING” ___________

Note 1 - For repeater operation, *5 23 shouid be turned on and *5 14

should be turned off. When *5 14 is on, the patch is in simplex
mode and *5 23, and *5 24 are used to modify the sample rate.

Note 2 - This is a two part switch. The following switch number must

also be set. Refer to the section in the manual for more detall
on setting these.

Note 3 - Switches 23 and 24 have different uses for simplex and duplex

operation. If switch 14 is on and 36 is off, then 23 and 24
are used to adjust the sample rate for simplex use. If 14 is
off, and 36 is on, then 23 is used for "Repeat Enable" and 24
is for "Courtesy Beep" during dúplex use.

NOTES:________________________________________________________________
______________________________________________________________________
______________________________________________________________________
______________________________________________________________________
______________________________________________________________________
______________________________________________________________________
______________________________________________________________________
______________________________________________________________________
______________________________________________________________________
______________________________________________________________________

Page # 41

C.E.S. Model SDI-50 Manual, Circuit Description

MODEL SDI-50 CIRCUIT DESCRIPTION

GENERAL DESCRIPTION

9.1
The CES Model SDI-50 consists of a microcomputer digital circuit
system, and an analog circuit system. These two systems are separated
on the circuit board, and have separate ground returns in order to
minimize cross talk. The Model SDI-50 is totally controlled by the
microcomputer program memory.

9.1.1

Microcomputer Control System
The CES SDI-50 is controlled by the Microcomputer chip Ul. All
operating parameters are controlled by the microcomputer program
memory and are executed by Ul.

9.1.2

Customer Programmable Memory
All customer programmable parameters are stored in Electrical
Erasable Proms U3 and U4 (if equipped). These CMOS chips are
4096 bit serial prom, internally organized as two 256 x 8 pages.
Data retention is specified to be greater than 100 years.

9.1.3

DTMF Encoding and Decoding
DTMF encoding and decoding is done by the DTMF Encoder-Decoder
circuit, U2. This microprocessor controlled peripheral
generates and decodes all 16 DTMF digits. DTMF data is passed
to and from U2 via the audio circuits and the Microprocessor
Control System. The Analog Switches control the path of
encoding and decoding in the Model SDI-50 depending on its
current state of operation. DTMF encoding signals are generated
on pin 8. This chip also contains a call Progress Tone
Detector. Pin 13 provides an output that is fed into the
Microprocessor for call progress tone detection. LED CR9 is a
DTMF strobe that flashes when the decoder has received a DTMF
signal.

9.1.4

Power Supply
The Primary Power Supply for the Model SDI-50 consists of 5.0
volt regulators, U7 and U8. Regulator U7 is used to power the
Microcomputer and the digital ICs. U8, which is aiso a 5.0 volt
regulator, is used to power the Analog System in Model SDI-50.
Separate power supplies are used to provide isolation between
the two systems. The inputs to these regulators are connected
together, and receive power from an external 12.0 volt power
suppiy.

9.1.5

Power on Reset
The Model SDI-50 has a "Power on Reset" circuit to monitor the
input voltage to the Model SDI-50, and provides a "Reset" pulse
to the Microcomputer Control System in the

Page # 42

C.E.S. Model SDI-50 Manual, Circuit Description

event there is a voltage drop to maintain system integrity.
This function is provided by CR1, Ql, and Q3.

9.1.6

Watch Dog Timer
The parts consisting of Q2 and U5 form a missing pulse detector.
Both halves of U5 are re-triggerable one shots. Durring normal
operation, Ul constantly sends pulses to U5 to keep it from
timing out. If for any reason the first half of U5 isn't re­triggered before it's time-out time (set by the time constant of
Cl and Rl), it will in turn trigger the second half of U5 which
will cause a reset to the microcomputer.

9.1.7

Telephone Line Circuit
The telephone line is connected directly to the back of the
Model SDI-50 via a cable equiped with RJ11-C connectors. A ring
detecter (U10) provides a square wave output at the ring voltage
frequency to Q8. This 20 to 40 Hz signal is filtered at the
gate of Q8 to próvido a single pulse for each ring to the
microcomputer.

Ull, Q9, and Q10 detect an "off hook" condition on the telephone
line. Q12, Q13, Q14 and diodos CR18 through CR21 provide an
electronic holding coil to sink off hook current. Line
transformer TI couples telephone and radio audio. This single
transformer provides 35dB of isolation as a fuli duplex hybrid.

Audio from the radio receiver is filtered by a high pass filter,
U17, that removes frequencies below 300 Hz. The level of audio
is adjusted by R60 and is de-emphasized by U13. Receive audio
is then amplified and directed into the hybrid by U16. Where
de-emphasis of RX audio is required, JMP2 is installed, which
places C31 into the feedback path of U13.

Audio from the phone line is amplified and limited by U15. The
level to the transmitter is controlled by R75 and is then
amplified and buffered by U13.

Repeat audio level is controlled by R61 and returned to the
transmitter by U13.

9.1.8

VOX Detect Circuit
U15 amplifies telephone line audio and drives a detector network
that gives a peak DC reading on the amount of audio set by R99.
This DC voltage is fed to comparator U19 which provides a logic
level output to the microcomputer.

9.1.9

Noise Circuit
The noise circuit consists of U16 and U18. Audio from the
receiver is coupled to U16, which is a high pass filter with
cutoff of 8 Khz. This filter eliminates all voice signals and
allows the noise circuit to monitor channel

Page # 43

C.E.S. Model SDI-50 Manual, Circuit Description

noise oniy. The level of noise on the radio channel indicates
the presence or absence of an RF carrier. The noise level is
adjusted by R91 and sent to a network that gives a peak DC
reading of the amount of noise on the channel. This signal is
sent to a comparator (half of U18) that provides a logic level
signal to the microcomputer.

9.1.10

CTCSS Level Comparator
U17 is a comparator with adjustable threshold (set by R45) which
is used to convert the DC voltage from the radio decode circuit
to the proper logic level for the microcomputer.

Page # 44