2070-9D
2070-9A
2070-9B
2070-9E
USER’S MANUAL
33.6K SMART MODEM
June 11, 2009
PRELIMINARY
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and agrees not to dislcose this data or any portion
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the prior written consent of GDI Communications
LLC. Recipient further agrees not to incorporate
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THIS LEGEND SHALL BE INCLUDED ON
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Proprietary Data
product or endeavor.
GDI COMMUNICATIONS, LLC
280 I-80 West Exit 1
PO BOX 1330
Verdi, Nevada 89439
Phone: 775-345-8000
FAX: 775-345-8010
www.sgdi.com
PRELIMINARY
TABLE of CONTENTS
GLOSSARY..........................................................................................................................................................1
GERNERAL DESCRIPTION.............................................................................................................................2
GENERAL CHARACTERISTICS.....................................................................................................................3
INDICATORS, CONNECTORS, AND SWITCHES........................................................................................5
Dialup Indicators..........................................................................................................................................5
RJ45 Termination Table ...............................................................................................................................5
DB9 Termination Table................................................................................................................................5
C20 Termination Table.................................................................................................................................5
96 pin edge connector...................................................................................................................................6
INSTALLATION .................................................................................................................................................7
Dialup Configuration Switches.....................................................................................................................7
DISTANCE OR MAXIMUM UNITS PER LINE .............................................................................................9
SYSTEMS WITH NO RTS SIGNAL................................................................................................................9
SYSTEM PROBLEMS..............................................................................ERROR! BOOKMARK NOT DEFINED.
THEORY OF OPERATION.............................................................................................................................12
DIALUP MODEM ...............................................................................................................................................12
FSK OPTION.....................................................................................................................................................13
BLOCK DIAGRAMS ............................................................................................................................................14
Dialup Block Diagram................................................................................................................................14
FSK Expansion Block Diagram..................................................................................................................15
MAINTENANCE...............................................................................................................................................16
PREVENTATIVE MAINTENANCE ........................................................................................................................16
TROUBLE ANALYSIS .........................................................................................................................................16
TROUBLE SHOOTING SEQUENCE CHART............................................................................................................ 16
WAVEFORMS....................................................................................................................................................17
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2070-9x User’s Manual Page 1
GLOSSARY
Anti-Streaming – A function on GDI
modems that prevents a Host from
transmitting continuously.
DCD – Data Carrier Detect. An EIA RS232D control signal that can be used
to gate RXD to a DTE.
DCE – Data Communications
Equipment. A device that converts
data from a DTE to a transport stream.
For example. The GDI model 400
modem is a DCE that converts RS232
data from a controller to a FSK Telco
system.
DTE – Data Terminal Equipment. A
device that initiates communication
over RS232 lines.
CTS – Clear To Send. A EIA RS-232D
control signal that can be used to gate
TXD data from a DTE.
Full duplex – A communication
system where data can be transmitted
in both directions at the same time.
Half duplex - A communication
system where data can be transmitted
in only one direction at a time.
FSK – Frequency Shift Keying.
Communication protocol where data is
encoded into binary format and
represented by different frequencies.
Host – Any DTE device.
MARK – Signal state of a FSK system
that represents a logical “1” value.
Private wire – Telco communication
hardware that is leased for private
use.
SPACE – Signal state of a FSK system
that represents a logical “0” value
0 dBm – Represents the signal level
required to produce 1mw in a 600Ω
load.
Soft carrier
Surface mount parts – Electronic parts
that are designed to be soldered to
pads instead of vias.
RXD – Receive Data. An EIA RS-232D
data signal that transfers information
in form of binary data to a DTE.
RTS – Request To send. An EIA RS232D control signal that can be used
to gate TXD to a DTE. The DTE
asserts RTS and then waits for the
DCE to respond with CTS.
TXD Transmit Data. n EIA RS-232D
data signal that transfers information
in form of binary data from a DTE.
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2070-9x User’s Manual Page 2
GERNERAL DESCRIPTION
The 2070-9xx is a 33.6Kbps dial-up
modem in a form factor designed for
use in a Model 2070 Controller.
It is compatible with other V.34
modems and is designed for traffic
control environments.
Located on the front panel of the 20709xx is a RS-232 port that can connect
the dialup modem to a computer
through a female DB9 connector. This
port can also be connected to the
2070’s I/O bus.
The phone line connects to the 20709xx through a standard RJ-11
connector located on the front panel.
A second RJ-11 connector is provided
for connection to a telephone.
The 2070-9xx can automatically
negotiate line rates from 300bps to
33600 bps.
All operating parameters such as
speed, etc., can be configured using
industry standard AT commands.
The serial port has a maximum speed
of 115.2 Kbps and is RS-232 and V.24
compatible.
The 2070-9xx cannot be used with
leased lines.
The SM336 also features Auto Answer,
Auto Dial, and tone or pulse dialing.
The 2070-9xx can be factory fitted with
a FSK Expansion Card. which is a FSK
Private wire Modem.. FSK stands for
Frequency Shift Keying which is a
modulation scheme that Shifts
(changes) the frequency to represent a
digital “1” (SPACE) or an “O” (Mark).
The FSK option can be configured for
the following baud rates:
2070-9A: 1200bps serial,
1200Hz/2200Hz Mark/Space
Frequencies, and 900Hz Soft Carrier
frequency
2070-9B: 9600bps serial,
11200Hz/17600Hz Mark/Space
Frequencies and 7800Hz Soft Carrier
frequency.
2070-9E: 19200bps serial,
19200Hz/38400Hz Mark/Space
Frequencies and 13800 Soft Carrier
Frequency.
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2070-9x User’s Manual Page 3
GENERAL CHARACTERISTICS
FORM FACTOR
Standard 2070 plug in board size:
8.375” x 5.69” x 1.592”
Temp………..-37 to +74 degrees C.
Humidity…….5 to 95 % noncondensing.
Power …….….5 V @ 500ma
+12V @ 100 ma
-12V @ 100ma
DIALUP:
Modulation……..Quadrature Amp.
Mod.
Modem…ITU V.34 and Rockwell V.FC
Interface…ITU V.24/V.28, EIA-232
Data Throughput…..115.2 Kbps
Data Rates:
33.6Kbps, 31.3Kbps, 28.8Kbps,
26.4Kbps, 24.0Kbps, 21.6Kbps,
19.2Kbps, 16.8Kbps, 14.4Kbps,
12.0Kbps, 9.6Kbps, 7.2Kbps, 4.8Kbps,
2.4Kbps, 1.2K baud, 300 baud.
The modem will automatically select
the best operating speed. Speeds are
±0.01%.
Specifications: V.34, V.32 bis, V.32,
V.22
bis, V.22A/B, V.23, V.21,
Bell 212, Bell 103, V.33,
V.17, V.29, V.27, V.21
Channel 2
Error Correction….V.42 LAPM, MNP24,
MNP 10
Data Compression…V.42 bis, MNP 5
Loop Tests….. ITU V.54 loop2
(RDL) and
Loop 3 (LAL)
Data Carrier…….1800 ± 0.5 Hz
Calling Tone……1300 ± 10 Hz
Answering Tone…2100 ± 15 Hz
Receiver Freq. Tolerance…….±14 Hz
S/N Ratio…………..-26 dB
Dynamic Range……-12 dBm to –42
dBm
Transmit Level: Fixed at –11 ±2 dB
Ring detect Sensitivity…. 38 VRMS
Ring Equiv. Number….…1 Bel
Termination………600 Ohm
Return Loss… Better than 14 dB
between
200 and 4000 Hz
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2070-9x User’s Manual Page 4
FSK:
Serial Data Rate……..0-19,200 baud.
Meets EIA RS-232D and CCITT V.24
electrically
CTS Delay .......................12 ±2 ms
Soft Carrier Turnoff Time 10 ±2ms
Receive Squelch ............6.5 ±1ms
Carrier Detect Time........8 ±2ms
Data Format…Asynchronous, serial by
bit
Line interface…..Private Metallic wire
600 Ohm
Modulation…….Phase Coherent FSK.
Modulation Frequencies:
Mark and Space Frequencies have a
±1% tolerance.
Frequency 2070-9A 2070-9B 2070-9E
Mark 1200Hz 11200 Hz 19200 Hz
Space 2200 Hz 17600 Hz 38400 Hz
Soft Carrier 900 Hz 7800 Hz 13800 Hz
4 wire Full Duplex and 2 wire Half
Duplex
Receive Sensitivity….0 to -40 dB.
Output Level……Continuously
adjustable from -8dBm to 0 dBm. (set
to 0dBm)
Anti-streaming
RTS Trigger mode time-out 7s.
Loss of Data mode time out 7s.
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2070-9x User’s Manual Page 5
INDICATORS, CONNECTORS, AND
SWITCHES
Dialup Indicators:
Transmit Data TX
Receive Data RX
Data Terminal Ready DTR
Data Carrier Detect DCD
Data Set Ready DSR
Ring Indicator RI
Dialup Connectors:
Phone Connector RJ11
Line Connector RJ11
RJ45 Termination Table
Pin Signal
1 NC
2 TIP
3 RING
4 NC
Configuration Port DB9
DB9 Termination Table
Pin Signal
7 RTS
4 DTR
8 CTS
6 DSR
3 TXD
1 DCD
9 RI
2 RXD
FSK:
Receive Data……….…RXD
Data Carrier Detect…...DCD
Transmit Data…………TXD
FSK on board Indicators
Request to Send……….RTS
Clear to Send………….CTS
FSK Enable/Disable switch
FSK Full Duplex/Half Duplex switch.
FSK / EIA 232C Connector (C20)
C20 Termination Table
C20
Pin Function Pin Function
A Audio In J RTS
B Audio In K Data In
(TXD)
C Audio
Out
L Data Out
(RXD)
D +5 VDC M CTS
E Audio
N DC Gnd #1
Out
F NA P NA
H CD R NA
Board Power On/Off switch.
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2070-9x User’s Manual Page 6
96 pin edge connector
Pin A B C
SP1-TXD+
1
SP1-TXD-
2
SP1-RXD+
3
SP1-RXD-
4
SP1-RTS+
5
SP1-RTS-
6
SP1-CTS+
7
SP1-CTS-
8
SP1-DCD+
9
SP1-DCD-
10
SP2-TXD+
11
SP2-TXD-
12
SP2-RXD+
13
SP2-RXD-
14
SP2-RTS+
15
SP2-RTS-
16
SP2-CTS+
17
SP2-CTS-
18
SP2-DCD+
19
SP2-DCD-
20
DC Gnd C50 EN
21
22
DC Gnd
23
24
25
26
DC Gnd #1 DC Gnd DC Gnd
27
+12 Serial
28
+5VSerial +5VSerial
29
DC Gnd #1 DC Gnd DC Gnd
30
31
32
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2070-9x User’s Manual Page 7
INSTALLATION
Installation of the 2070-9 is relatively
simple. It can be installed with the
power on provided that the power
switch on the front panel is in the
“OFF’ position.
The 2070-9xx receives power from the
Model 2070 Controller, and the
Controller
The incoming phone line is to be
connected to the RJ-11 “LINE”
connector . An external phone can be
connected to the RJ-11 labeled
“PHONE.”
Note: As the RJ11 connectors are
connected in parallel, remember not to
use the phone while the modem is in
operation.
Configuring the 2070-9xx is achieved
through a series of switches on the
front panel and on the board itself.
The configuration switches for the
dialup modem are located on the top
of the main board closer to the front
panel. Refer to the following table
when configuring the modem:
Dialup Configuration Switches
Switch Closed Open
1-DB9 SP2 Dial Up
2-DM9 mode DCE DTE
3-RTS mode High Normal
4-RS-485 Normal Inverted
5-Future
Expansion
Switch 1: Default = Open.
Open - When switch 1 is open the
dialup modem can be configured via
the front panel DB9 connector.
Closed When switch 1 is closed, the
DB9 is connected to the controllers
SP1 port.
Switch 2: Default = Closed.
Open-When switch 2 is open, the
directionality of the port is DTE.
Closed-When switch 2 is closed, the
directionality of the port is DCE.
Switch 3: Default = Open.
Open-RTS/CTS handshaking is active.
Closed-RTS/CTS handshaking is not
active and RTS is asserted constantly.
Switch 4: Default = Open
Open-The RS-485 signals are inverted.
Closed-The RS-458 signals are not
inverted.
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2070-9x User’s Manual Page 8
FSK Configuration Switches
Switch
FUNCTION
Pos.
1 Full Duplex (ON)
Off for Half
2 Half Duplex (ON)
Off for Full
3 RTS timing ON =
short timing
4 Soft Carrier Timing
ON=Short timing
5 Rec Squelch--ON
for Half duplex
6 Rec Squelch
Timing ON for
short timing
7 Carrier Detect
timing ON for
short timing
8 Anti-Streaming
ON=enabled
For normal 4 wire Full Duplex
operation, switch 1 should be ON and
everything else should be OFF. This
will select standard timing and full
duplex operation. If Anti-Streaming is
required, turn switch 8 ON.
For Normal 2 wire Half Duplex
operation, switches 2 and 5 should be
ON and everything else is OFF. Turn
switch 8 ON if Anti-Streaming is
required. Only the Audio Out
transformer is used for 2 wire
operation. Switch 2 connects the input
amplifier of the receiver to the board
side of the Output transformer so that
signals coming into the transformer
are available to the receiver. Switch 5
enables the Receiver Squelch, which
turns RXD OFF when the Modem is
transmitting.
In the 4-wire full duplex mode of
operation, there is no connection
between the Transmitter circuit and
the Receiver circuit. In the 2-wire
mode, the transmitter output is
connected to the Receiver input.
For further adaptation, all of the timing
signals can be configured to be half
their normal time. Switch position 3
reduces the CTS delay to 6ms.
Position 4 reduces the Soft Carrier
time to 5ms. Position 6 reduces the
Receiver Squelch time to 3.2ms. (This
is the time, in a 2 wire half duplex
system, that the Receiver is held OFF
after a transmission). Switch position
7 reduces the Carrier Detect time to
4ms.
These faster timing can be used in a
system where you are running out of
time in polling a large number of
intersections. While the faster timing
will allow for more modems in the
same network, it also allows for more
system errors. All modems have to be
set for the faster timing.
Switch position 8 on the dipswitch
turns the Anti-Streaming circuit on
and off. The Anti-Streaming circuit will
turn off the Transmitter after it has
been transmitting for 7 seconds
continuously. This will prevent a
single malfunctioning Controller from
interfering with other remote modems
on the same line. This feature is
typically used on remote/slave
modems where the transmitted data
packets are short. The anti-streaming
circuit will be active until RTS is deasserted. When RTS goes low, the
anti-streaming circuit will reset
automatically and the Controller can
then transmit again.
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2070-9x User’s Manual Page 9
The Anti-Streaming feature is not
normally activated on a Local/Master
modem since they are transmitting
continuously to all of the
remotes/slaves. If there is a possibility
that a message may go over 5
seconds, do not use the AntiStreaming Feature.
The Input impedance can be changed
with switch 8. Normally, the 600 Ohms
position is used but where reduced
loading is required, the high
impedance position can be used for
units not at the end of a line.
SHORT TIMING
In a system with many Modems on a
line, you may find that you can’t get to
every Controller in the allotted time
period. By switching over to the Short
timing positions on the dipswitch you
can save 12 ms per poll and response.
To use short timing switches 3, 4, 6,
and 7 should be turned ON for all of
the units on a particular line.
As mentioned previously, there is the
possibility of more communication
errors with short timing. You will have
more errors because there is a greater
possibility of noise activating one of
the Carrier Detect circuits. Once the
receiver is turned on, the error rate is
the same. On systems with good
quality wire, you may not notice any
change in system errors.
DISTANCE OR MAXIMUM UNITS PER
LINE
The signal level on a line is
determined by:
1. The length of the line
2. The quality of the line
3. The number of units on the line.
4. The transmitted signal level
We can do anything about the length
and quality of the line but we can
adjust the transmitted signal level and
the input impedance of the 496
Modem.
The output level of the 496 is set at the
factory to 0 dBm. A 0 dBm signal is
normally good enough to give you a
range of 5-6 miles on 22 AWG wire. 19
AWG wire will give you another 20%
more distance. The output signal level
can be increased to +10 dBm by
adjusting the potentiometer VR2,
which is labeled “AMP”. This can give
you as much as 25% more distance.
The signal levels are measured across
a 600-Ohm resistor. If you are going to
measure the output level, load the
output with one other modem or use a
600 resistor, which is more accurate.
The potentiometer VR2 (AMP) will
provide an adjustment range of –8 to
+10 dBm. Increasing the output level
may increase the cross talk in some
systems.
Another way to get more distance or
more units on a run is to raise the
impedance of the modems in the
middle of a line. The two end units are
left at 600 Ohms input impedance but
the units between them are changed
to 4.75K. This is done by moving the
jumper on JP1 to the 4.75K position
from the 600 position. This will reduce
the loading effects caused by the
input impedance of the modem.
SYSTEMS WITH NO RTS SIGNAL
Some computers or camera systems
may not have the standard
PRELIMINARY
2070-9x User’s Manual Page 10
handshaking signals RTS and CTS.
The 496 needs to have the RTS signal
before it will transmit. In a 4-wire
system where the modem can
transmit continuously (at a master or a
point to point system), the JP2 jumper
can be installed which will force a RTS
signal into the modem. This will cause
the modem to transmit continuously.
This will not cause a problem at a
Master Modem or in a point-to-point
system. This will not work for modems
that are connected to local controllers
that share a line going back to a
Master. The RTS pin on the edge
connector is pulled up with a 1.0K
resistor to +12V so make that nothing
is connected to the RTS pin (L).
If you are in a situation where you
don’t have control of RTS but you
have more than one modem on the
line, you will have to use a Key On
Data device to control the Modem. GDI
can supply these devices. Please
contact the factory for more
information.
A common problem in 4-wire systems
is not connecting them correctly. The
pair of wires from the Audio Out from
the Master Modem is connected to the
Audio In of all of the remote Modems.
All of the Audio Out signals from all of
the Remote Modems are connected
together and connected to the Audio
In of the Master. The Audio signals are
transformer coupled and are not
polarity sensitive.
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2070-9x User’s Manual Page 11
ADJUSTMENTS
The only adjustment that should be
made to the FSK Expansion modem is
the output level. VR2 potentiometer
(labeled AMP) is used to make that
adjustment. The Audio output must be
loaded with 600 Ohms and the output
level measured across the 600-Ohm
resistor. You have an adjustment
range from –8 to 0 dBm.
The two other potentiometers on the
board should not need adjustment for
the life of the modem and require
special equipment to set correctly.
Contact the factory if you feel these
need adjustment.
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2070-9x User’s Manual Page 12
THEORY OF OPERATION
Dialup Modem:
The 2070-9xx provides a Hayes
compatible dialup smart modem
interface to the 2070 controller.
Power to the board can be switched
on and off from a front panel SPST
switch. This switch, when on,
provides a current path for the quad
SPST relay that connects/disconnects
the controller power supply to the
2070-9.
Isolation from the controller’s power
supply is provided by a encapsulated
transformer coupled DC to DC
converter which provides the
necessary power for both the smart
modem and the FSK Expansion Board.
Isolation from the 2070 controllers I/O
bus is provided by the use of optoisolaters that link the signals from the
controller to the smart modem while
isolating power and ground.
The RS-485 signals are first converted
to TTL using single supply line
drivers. The signals are then fed to
the opto-isolators.
The ouputs of the opto-isolaters are
fed to a PLD.
The functionality of the “
Logic Device” is “created” by the GDI
engineering staff not by the
manufacturer of the part. This makes
it possible to make the modem
configurable for different modes of
operation without the need for dozens
of costly descrete components,
switches, and jumpers. It also
Programable
provides a means for making rapid
changes to the functionality without
increasing the cost to the user.
There are four switches connected to
the PLD which configures all modes
for the board. This includes RTS/CTS
handshaking modes, RS-485
inversion, and DB9 configuration.
The PLD then routes the signals to the
correct outputs. The signals from SP1
are always routed to the smart modem
module. The signals from SP2 can be
routed to the front panel DB9. But,
normally, the DB9 is connected to the
smart modem which provides a means
to manually configure it using the AT
command set.
However, the smart modem is
typically configured “on the fly” by the
controller via SP1 using an AT
command string.
The signals are then modulated/DeModulated by the smart modem and
transmitted/Received out/in the RJ11
connecter after first passing through
the line filters. The line filters filter out
and noise from the telephone system
that might create signal degradation
and cause errors.
The logic state of the signals are
displayed on the front panel useing
LEDs. When the LED is lit, the signal
is active. Each status signal is
buffered by an N-Channel MOSFET
transistior which provides the
necessary current for the LED.
The speaker is driven by a monolithic
700-mW low-voltage power amplifier
which is connected directly to the
smart modem.
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2070-9x User’s Manual Page 13
The ouput signals from SP2 are
directly connected to a 50 pin socket
which the FSK Expansion Board plugs
in to. The Expansion Board provides
all signal isolation to both the
controller and the line.
FSK Option
The Space Frequency is used to
transmit a digital “1” and the Mark
frequency is used to transmit a digital
“0.” At the end of the data
transmission, the Soft Carrier
frequency is transmitted for 10 ms.
The Soft Carrier is to causes the
receiving modems receiver section to
shut down. This prevents noise from
getting though the Receiver.
The Receiver section of the modem
amplifies the signal it receives
through the coupling transformer and
filters it so that only frequencies in the
correct band will get passed on to the
demodulator. Signals as low as 6
milliVolts will produce RS-232 level
signals (±12V) at the receiver output.
Further noise prevention is
accomplished through the use of
special filter circuits which are used to
enable the Carrier Detect Signal.
There must be 8ms of the Mark
frequency present on the input for
Carrier Detect to activate.. When the
Carrier Detect signal goes active, the
Receiver will be enabled. That Mark
signal will also have to be above a
certain threshold before the Mark
detect circuit will be activated.
The CTS delay circuitry will cause the
Mark frequency to be present on the
receivers input for 12ms. When RTS
(Request to Send) is asserted, the
modem starts transmitting the Mark
frequency. The Host Computer or
Controller will not send data until CTS
is asserted.
Data Carrier Detect (DCD) controls the
output of the Receiver and can be
used to key the Controller or Host
Computer. The no-signal state of the
RXD signal is -12vdc or “Mark.”
At the end of a data transmission the
Controller or Host Computer deasserts RTS which causes the modem
to transmit the Soft Carrier frequency
for 10ms.
At the receiving end, the “in-band”,
“out-of-band”, and “soft carrier” filters
all cause the receiver to shut down.
Without these special filters, the
receiver could respond to the
transition from soft carrier to no signal
and could create a false start bit.
The Block diagram of the FSK modem
shows how the different sections of
the modem are interconnected.
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2070-9x User’s Manual 14
Block diagrams
Dialup Block Diagram
PRELIMINARY
2070-9x User’s Manual 15
FSK Expansion Block Diagram
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2070-9x User’s Manual 16
MAINTENANCE
Preventative Maintenance
There is no preventative maintenance required or anything that needs to be
adjusted for the life of the product.
Trouble analysis
The model 2070-9xx is a fairly complex Modem with hundreds of parts. This makes
this Modem hard to trouble shoot for the average technician with limited experience.
It also requires special soldering tools to work with the surface mount parts. On the
other hand this modem is constructed with top quality parts and so you will not
experience many failures.
The chart on the next page will help find the problem if you decide to fix the model
400 yourself.
Trouble shooting Sequence chart
PROBLEM CAUSE
The board is non-functioning Power coming into the board or
could have a problem. Check
connectors
Modem is not generating Mark and
Space Freq.
Transmitter turns Off after 6
seconds
No Receive Data
RXD and CD LEDS off
No Receive Data
no LEDs
No Receive Data
CD LED on
No RTS or TXD coming from Host.
Check edge connector, Q8, Q7 and
U8.
Anti-streaming is turned on and
transmissions of more that 6
seconds are being used.
Check edge connector, U1, U2, and
U3..
Check output of input filter U1 pin8,
you should have a strong signal at
this point.
Check Demodulator section. UU6.8,
U6.14, and U5.14 should be close to
+12v.
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2070-9x User’s Manual 17
Waveforms
Signal Characteristic Waveform
OSC out
Mark Frequency 1200Hz
OSC out
Space Frequency 2200Hz
Soft Carrier
Frequency
Alternating Bit
Pattern
900Hz
1720Hz
OSC out
Audio Out
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2070-9x User’s Manual 18
RXD
Symmetry 50%
RTS
CTS Delay 12ms
DCD 8ms
Soft Carrier time 10ms
CTS
RTS
DCD
Audio In
RTS
Soft Carrier Enable
Audio Out
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2070-9x User’s Manual 19
RTS
Receiver Squelch
Time
Voltage Measurements
Recvr.
6.5ms
Squelch
Enable
For DC Isolated Models
TP Measurement tolerance
TP13 5vdc ±.2vdc
TP11 -5vdc ±.2vdc
TP10 +5vdc ±.2vdc
For non-Isolated Models
TP Measurement tolerance
TP13 12vdc ±.6vdc
TP11 -12vdc ±.6vdc
TP10 +5vdc ±.2vdc
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2070-9x User’s Manual 20
GDI COMMUNICATIONS, L.L.C.
TRAFFIC EQUIPMENT MANUFACTURER ♦ SPECIALIZING IN COMMUNICATIONS
280 I-80 WEST EXIT 1
P.O. BOX 1330
VERDI, NEVADA 89439
TELEPHONE: 775-345-8000 FAX: 775-345-8010
PRELIMINARY
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