TTI LTX-5510 User manual

Operating Instructions
Terahertz Technologies Inc. 169 Clear Road, Oriskany, NY 13424 [phone] FAX [phone]
E-mail [email protected]
6/2011
LTX-5510 and LTX5515
Fiber Optic Link

Quick Start Page
1. Connect a multimode ber optic patch cord between the ST connectors on the rear panels
of the LTX-551XT (transmitter) and the LTX-551XR (receiver).
2. Set the transmitter controls as follows: POWER - Off
INPUT Z - 1 M
RANGE - ± 5 V
3. Set the receiver controls as follows: POWER - Off
4. Connect the power supply plugs to the connector on the back of each unit.
5. Plug the power supplies into a wall socket.
6. Connect a signal source to the transmitter Input BNC connector.
7. Connect the receiver output to an oscilloscope.
8. Switch the receiver power switch to ON. (NOTE: The order of steps 8 and 9 is crucial)
9. Switch the transmitter power switch to ON.
10. The input signal should now be visible on the oscilloscope.

Contents
Introduction............................................................................................................................1
Unpacking and Inspection............................................................................................1
Power Considerations......................................................................................................1
Description / Features......................................................................................................2
Theory of Operation......................................................................................................3
Operating Considerations.....................................................................................................4
Specifications..............................................................................................................5
Service/Warranty Information..........................................................................................6

Introduction
The LTX-551X Electrical to Optical and Optical to Electrical Converter system comprise a convenient
product that is intended to transmit analog and digital information to a remote location via ber
optic cable. Its primarily designed to be used in those situations where the signal of interest has a
high common mode voltage with respect to the measurement equipment. Such situations arise in
plasma physics experiments, power transmission equipment, and high power laser systems. Trigger
information from electrically noisy sources such as high current discharge laser systems may be
transmitted without conducting Electro-Magnetic Interference, (EMI) to the measurement or control
equipment.
Thees systems transmit an analog signal plus four digital input channels simultaneously. The input
analog signal may range in frequency from DC to 12.5 MHz (-3 dB point) for the LTX5510 and DC to
25 MHz (-3 dB point) for the LTX5515. The digital signals may switch at up to 12 MHz rates for the
LTX5510 and at up to 25 MHz rates for the LTX5515, and are independent. The analog input may
be terminated at 1 Megohm or 50 Ohms depending on the front panel switch. The output impedance
is always 50 ohms. Analog signals may range from -5 to +5 volts. The output signal will have a one-
to-one correspondance, i.e. a gain of +1. When the front panel selector switch is set to +/- 1V F.S.
the gain is +5, ie. a 1 volt input signal will result in a ve volt output signal. The digital inputs accept
TTL, CMOS or LVTTL levels and output LVTTL levels, i.e. 0 to 3.3V for a logic zero and logic one
respectively. The sense is non-inverting.
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Unpacking and Inspection
Prior to shipment this instrument was inspected and found to be free of mechanical and electrical
defects. Upon acceptance by the carrier he assumes responsibility for its safe arrival. After unpacking,
examine the unit for any evidence of shipping damage. Should you receive this instrument in a
damaged condition, apparent or concealed, it must be noted on the freight bill or express receipt and
signed by the carrier’s agent. Failure to do so could result in the carrier refusing to honor the claim.
Upon ling a claim TTI should be notied.
Power Considerations
The LTX-551X Transmitter and Receiver operate from a regulated 9 VDC wall-mount power supply.
These power supplies operate with line voltages ranging from 95 to 260 VAC, 50-60 Hz. Four
interchangeable power line connectors are supplied that are compatible with connectors used in
North America, Continental Europe, Australia, and the United Kingdom. Do not use with any other
wall-mount supply or damage may result.

Description / Features
Power Switch
Input Overload
Indicator
Input Impedance
Selector
Input Range
Select
Digital Input
Connector
Analog Input
Connector
2
Power Switch
Optical Signal
Indicator
(good when lit)
Digital Input
Connector
Analog Output
50 ohms
LTX551X Transmitter
LTX551X Receiver

Theory of Operation
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The LTX-5510T amplies, lters and digitizes the input analog signal to 12-bit precision at a 50 MS/s rate
and the LTX5515T at 100MS/s. The twelve bit digital data from each sample is combined with the state
of the four digital input channels to form a sixteen bit word. This word is converted to an 8b/10b code
and transmitted as a twenty bit word. This process is repeated at a 50 MHz for the LTX5510, resulting
in a 1 Gb/s data stream and at a 100 MHz rate for the LTX5515 resulting in a 2 Gb/s data stream. This
data is converted to an optical bitstream and transmitted via a user-supplied optical ber to the LTX-
551XR receiver.
The LTX-551XR receives the optical bitstream and converts it to a digital signal. It then decodes and
de-multiplexes this data. Twelve bits are presented to a fast D/A converter and post amplier which
drives the analog output port and four bits are latched and presented at the digital output ports. The
system is intended to be used with 50/125 uM or 62.5/125 uM ber optic cable. (The LTX-551XSM is
intended for use with single mode ber).
Upon energizing the LTX-551XT, it transmits framing characters for a few seconds so that the receiver
can determine where a valid word in the data stream begins and ends. The receiver is phase-locked
to the transmitters data rate and will remain so unless the optical signal is disrupted in some fashion
such as removing an optical ber or power to one of the units.

Operating Considerations
The LTX-551X system may be used to transmit signals from a source that is distant or at a different
ground potential with respect to measuring devices such as an oscilloscope. The input signal must
be in the range of 0 - ± 1 V or 0 - ± 5 V depending on the range selected. Digital signals may be
transmitted as well. TTL, CMOS or LVTTL level signals are acceptable. The output signals are LVTTL
( 0-3.3 V).
For high speed signals transmitted via any signicant amount (electrical length comparable to rise/fall
times) of coaxial cable, a 50 ohm termination may be switched in to preclude distortion and reections
from a mismatched transmission line.
The power supply for the unit must be at roughly the same potential of the signal common mode
voltage. For example, using the unit at a 10 000 V potential while it is utilizing the wall mount power
supply at conventional line potential will result in a hazardous situation and certain damage to the
equipment. An isolation transformer with sufcient isolation voltage rating must be used to power the
wall mount supply.
The length of ber optic cable that may be used with the LTX5510 is typically 300 M for 62.5/125um
ber or 500 M for 50/125um ber and for the LTX5515 the typical distance is 150M for 62.1/125um
ber and 300 M for 50/125um ber. Fiber bandwidth and not loss is typically the limiting factor for
range with multimode units. The single mode version is limited by loss. Typical ranges of 10 km may
be achieved with this model using single mode ber.
When setting up the LTX-551X system, note that the transmitter must be turned on last! This
allows the receiver to detect the synchronizing framing characters. Meaningless signals will otherwise
be generated. Should sync be lost by disconnecting the optical ber, simply turn the transmitter off
and on.
The red LED labeled O.L. indicates that the input signal exceeds the maximum input voltage for the
range in use.
The green LED on the receiver indicates that the receiver is operating with an adequate optical input
signal. If the indicator goes out, the transmitter has lost power or the connecting ber is disconnected
or broken.
The controls and their functions are indicated on the following pages.
The output signal from the receiver has a 10 V peak to peak output into an open circuit. The
maximum output into a fty ohm load is 4 V peak to peak.
DIGITAL INPUT/OUTPUT
CONNECTIONS
Digital Ground
Chan. 5
Chan. 2
Chan. 3
Chan. 4
5
3
4
2
1
4

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TTI reserves the right to change specications without notice
Specications
LTX-5510 LTX-5515
Analog Signal Bandwidth DC to 12.5 MHz (-3 dB) DC to 12.5 MHz (-3 dB)
Input Voltage Ranges +/- 1 V or +/- 5 V (selectable)
Resolution 12 Bits
Transfer Accuracy +/- 0.1% Full Scale, +/- 20 mV offset
Signal Latency (with one meter of ber) Approximately 300 nS
A/D Sampling Rate 50 Megasamples/S 100 Megasamples/S
Input Impedance 50 Ohms or 1 Megohm || 20 pF, (selectable)
Output Drive Capability +/- 5 V open circuit, +/- 2 V into 50 ohm load
Output Impedance 50 Ohms
Digital Inputs TTL, LVTTL, CMOS compatible
Digital Outputs LVTTL ( 0 - 3.3 V)
Digital switching Rates 0 - 12 MHz 0 - 24 MHz
Digital Signal Edge Uncertainty 0 - 20 nS 0 - 10 nS
Laser Wavelength LTX-55XX-850; 850 nm+/- 20 nm, LTX-55XX-1310; 1310 nm +/- 20 nm
Optical Transmission Rate 1.0 Gb/S 2.0 Gb/S
Loss Budget 15 dB max
Optical Return Loss > 15 dB
Laser Safety Classification Class I safety per FDA/CDRH and
IEC-825-1 regulations
Typical Trans. Distances (850nm) 500 M - 50/125µ ber
300 M - 62.5/125µ ber
250 M - 50/125µ ber
150 M - 62.5/125µ ber
Typical Trans. Distances (1310nm) >10 KM with 9/125 micron ber
Fiber Optic Connectors ST standard, FC optional
LED Annunciators Provided Input Overload (TX), Optical Signal (RX)
Power Supplies Universal Wall Mount, W/US, UK, Continental Europe and Australian plugs
Power Requirements 95-260 VAC, 50-60 Hz, 16 VA Max
Operating Temperature 0 - 40 C
TX Dimensions (mm) 175 L x 105 W x 40 H
RX Dimensions (mm) 175 L x 105 W x 40 H
Weight (each) 0.46 Kg
Standard Warranty 2 yrs, Components and workmanship, 30 day Satisfaction Guarantee
Accessories Supplied 5 pin DIN connector for digital inputs/outputs, TX and RX

Service and Warranty Information
Service Information
Products manufactured by Terahertz Technologies Inc.(TTI) are designed and fabricated to provide
reliable performance. However, in the event that service is required, both telephone technical
assistance and factory repair services are available. Call [phone] for information.
For IN-WARRANTY REPAIRS, call us to obtain a Returned Material Authorization number, (RMA
Number). All products are to be returned to TTI with freight charges pre-paid. Those products sent
under warranty will be returned to our customers pre-paid. We cannot be responsible for returned
products that do not reference the TTI RMA number.
For OUT-OF-WARRANTY repairs, services are billable for both time and materials.
LIMITED WARRANTY
TERAHERTZ TECHNOLOGIES INC. (“TTI”) WARRANTS THAT TO THE FIRST PURCHASER, FOR A
PERIOD OF TWO YEARS FROM THE DATE OF RECEIPT, THAT THIS PRODUCT (“THE PRODUCT”)
WILL BE FREE FROM DEFECTS IN MATERIALS AND MANUFACTURING. THE FOREGOING
WARRANTY IS THE ONLY WARRANTY, EXPRESS OR IMPLIED, GIVEN BY TTI, I.E., THERE IS NO
WARRANTY OF FITNESS FOR A PARTICULAR PURPOSE. TTI HEREBY DISCLAIMS ANY EXPRESS
OR IMPLIED WARRANTY OTHER THAN THE WARRANTY IN THE FIRST SENTENCE TO THE
FULLEST EXTENT PERMITTED BY LAW. THE SOLE AND EXCLUSIVE REMEDY UNDER THIS
WARRANTY IS REPAIR OR REPLACEMENT AT TTI’S OPTION OF ANY PRODUCT THAT PROVES
TO BE DEFECTIVE IN MATERIALS OR MANUFACTURING WITHIN TWO YEARS OF RECEIPT OF
THE PRODUCT. NOTE: THIS WARRANTY DOES NOT APPLY TO ANY PRODUCT WHICH HAS BEEN
SUBJECT TO MISHANDLING, MISUSE, OR SERVICE BY UNAUTHORIZED PERSONNEL OR TO ANY
PRODUCT WHICH HAS BEEN DAMAGED, MODIFIED, ALTERED OR TAMPERED WITH.
TO THE FULLEST EXTENT OF THE LAW, TTI DISCLAIMS ALL LIABILITY FOR ANY OTHER
DIRECT, INCIDENTAL OR CONSEQUENTIAL DAMAGES ALLEGED TO BE CAUSED BY A
DEFECTIVE PRODUCT, I.E., TTI WILL NOT BE RESPONSIBLE FOR ANY PERSONAL INJURY,
PROPERTY DAMAGE OTHER THAN THE COST OF REPLACING THE PRODUCT OR ANY OTHER
MONETARY DAMAGE SUCH AS LOST WAGES OR PROFITS CAUSED BY ANY USE, ATTEMPTED
USE OR INABILITY TO USE THE PRODUCT. NOTE: BY USING THE PRODUCT, YOU AGREE
THAT REPAIR OR REPLACEMENT AT TTI’S OPTION WILL FULLY SATISFY TTI’S WARRANTY
OBLIGATION TO YOU, WHETHER IN CONTRACT, TORT, NEGLIGENCE, STRICT LIABILITY OR
OTHER APPLICABLE LAW.
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