Terahertz Technologies LTX-5510 User manual

LTX-5510 Electrical / Optical Converter
Operating Instructions
Terahertz Technologies Inc. 169 Clear Road, Oriskany, NY 13424 [phone] FAX [phone]
E-mail [email protected]

Quick Start Page
1. Connect a multimode fiber optic patchcord between the ST connectors on the rear panels of the
LTX-5510T (transmitter) and the LTX-5510R (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
Specifications............................................................2
Unpacking and Inspection.........................................4
PowerConsiderations.................................................4
Theory of Operation...................................................5
Operating Considerations...........................................6
Service/Warranty Information.....................................10

Introduction
The LTX-5510 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 fiber 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.
The system transmits 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). The digital signals may switch at up
to 12 MHz rates 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 five 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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Specifications
Analog Signal Bandwidth..................................................................................................DC to 12.5 MHz (-3dB)
InputVoltage Ranges.............................................................................................. +/- 1V and +/- 5V Full Scale
Resolution...................................................................................................................................................12 - bits
Transfer Accuracy.....................................................................................................................................+/- 0.1 %
Signal Latency (with one meter of fiber)..................................................................................................~300 nS
Sampling Rate..............................................................................................................................................50 Ms/s
Input Impedance.............................................................................................50 Ohms or 1 Megohm,selectable
Output Drive Capabilty........................................................................+/- 5V open circuit,+/- 2V into 50 Ohms
Output Impedance....................................................................................................................................50 Ohms
Anti-Aliasing Filter...................................................................................................................4 - Pole Chebyshev
Digital Inputs.........................................................................................................TTL,LVTTL,CMOS compatible
Digital Outputs............................................................................................................................LVTTL ( 0 - 3.3V)
Digital Switching Rates........................................................................................................................ 0 - 12 MHz
Digital Signal Edge Uncertainty................................................................................................................+/-10 nS
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Specifications
LaserWavelength................................... LTX-5510-850: 850 nm +/- 20 nm, LTX-5510-SM: 1310 nm +/- 20 nm
OpticalTransmission Rate.........................................................................................................................1.0 Gb/s
Loss Budget............................................................................................................................................. 0 - 15 dB
Optical Return Loss.................................................................................................................................... > 15 dB
Laser Safety Classification........................................Class I safety per FDA/CDRH and IEC-825-1 regulations
TypicalTransmission Distances (850 nm)............ 500 M with 50/125 MM fiber, 300 M with 62.5/125 MM fiber
TypicalTransmission Distances (1310 nm).................................................................10 KM with 9/125 SM fiber
Fiber Optic Connectors....................................................................STType standard,FC available on request
LED Indicators Provided.......................................Input Overload (transmitter),Optical Signal - ON (receiver)
Power Supplies............. Wall Mount,Universal, US,UK. Continental Europe,and Australian Plugs Included
Power Requirements..........................................................................................95-260VAC,50-60 Hz,16VA Max
OperatingTemperature Range....................................................................................................................0 - 40 C
Transmitter Dimensions (mm)...............................................................................................175 L x 104 5 x 40 H
Receiver Dimensions (mm).................................................................................................... 175 L x 104 5 x 40 H
Weight Each.................................................................................................................................................0.46 Kg
StandardWarranty..................... Two years,Components andWorkmanship, 30 Day Satisfaction Guarantee
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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 filing a
claim TTI should be notified.
Power Considerations
The LTX-5510T and R 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.
.
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Theory of Operation
page 5
The LTX-5510T amplifies, filters and digitizes the input analog signal to 12-bit precision at a 50 MS/s rate.
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 rate resulting in a 1 Gb/s data stream. This data is converted to an
optical bitstream and transmitted via a user-supplied optical fiber to the LTX-5510R receiver.
The LTX-5510R 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 amplifier 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 fiber optic cable. (The LTX-5510SM is intended for
use with single mode fiber).
Upon energizing the LTX-5510T 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 fiber or power to one of the units.

Operating Considerations
The LTX-5510 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 significant amount (electrical length comparable to rise/fall
times) of coaxial cable, a 50 ohm termination may be switched in to preclude distortion and reflections
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 sufficient isolation voltage rating must be used to power the wall mount supply.
The length of fiber optic cable that may be used is typically 300 M for 62.5/125 um fiber or 500 M for
50/125 um fiber. 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 fiber.
When setting up the LTX-5510 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 fiber, simply turn the transmitter off and on.
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1
DIGITAL INPUT/OUTPUT
CONNECTIONS
Digital Ground
Chan. 5
Chan. 2
Chan. 3
Chan. 4
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Operating Considerations
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 fiber 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 fifty ohm load is 4 V peak to peak.
5
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2
1

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Operating Considerations

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Operating Considerations

Warranty and Repair Information
REPAIR 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.
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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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