OLP-55

OLP-55Optical Power Meter

Operating Manual

BN 2277/01

BN 2277/02

BN 2277/03

BN 2277/04

BN 2277/98.1101/04.11English

Please contact your local Acterna Sales Company if you have any questions regarding this product. The addresses are listed at the end of this manual.

CopyrightsThis product or parts of this product are based on the Recommendations and/or Standards issued by the Standardization Sector of the International Telecommunications Union - ITU-T and/or the European Telecommunications Standards Institute - ETSI. These Recommendations and Standards are copyright to these organizations. ITU-T Recommendations or ETSI Standards may not be copied and/or made available to third parties in whole or in part without the written agreement of ITU-T and/or ETSI.

Acterna Germany GmbHMühleweg 5, 72800 Eningen u. A.

Note: Changes may be made to specifications, descriptions and delivery information.© Copyright 2004 Acterna, LLC. All rights reserverd.“Acterna”, “Communications Test and Management Solutions” and the Acterna logo are registered trademarks of Acterna, LLC. All other trademarks and registered trademarks are the properties of their respective owners.

Printed in Germany

Order no.: BN 2277/98.11Version: 01/04.11Previous version: -

Acterna OLP-55 i

Contents

Contents

1 Introduction 1

The OLP-55 Power Meters 1Symbols used in this operating manual 2

2 Safety Information 5

3 Getting Started 8

Unpacking the device 8Device overview 9Power Supply 11Battery operation 12Operation from AC power 14Fitting adapters for plug connectors 15

4 Operation 16

Power ON/OFF 16Measurement Display 17Main Menu 18Configuration Menu 19Basic settings 20Selecting a wavelength 21Editing the λ-Table 21Auto λ mode 23Display absolute power level 25Display relative power level 26Maintenance 27

5 Memory Management 28

General Information 28Saving results successively 29Displaying stored results 30Saving results at a selected position 32Clearing the memory 33Read out the result memory 34

ii Acterna OLP-55

Contents

6 Remote Control 35

Communication interface 35Key 35Parameters 37

7 Measurement Example 44

Example: Attenuation measurement 44

8 Specifications 47

BN 2277/01 47BN 2277/02 48BN 2277/03 49BN 2277/04 50General specifications 51

9 Ordering Information 53

Index 54

Acterna OLP-55 1

1 INTRODUCTION

1 INTRODUCTION

The OLP-55 Power Meters

The handheld Optical Power Meters• OLP-55/01, • OLP-55/02, • OLP-55/03 and • OLP-55/04 measure power levels on fiber optical systems. Theys are designed for highest performing testing of all optical signals and systems, i.e. broadband, PONs, and Gigabit Ethernet. Battery operation with four AA batteries and the robust, shock-proof and splash-proof design allow a long operation time in the field even under tough conditions. AC line operation via a separate AC adapter and the USB interface for remote control allow also comfortable use in labs or production environments.

Common featuresAll power meters can connect to singlemode and multimode fibers with a max. core diameter of 62.5 µm (OLP-55/01: 100 µm).Tests on systems from different manufacturers with different connector types are easy to handle due to the UPP adapter for 1.25 and 2.5 mm ferrules.To measure attenuation, a suitable optical source is required. The ACTERNA OLS-55 Optical Light Sources are ideal for this application.Both modulated and unmodulated light signals can be measured. For modulated light signals, the average power is displayed.The modulated signal mode with different fixed frequencies can be used to identify fibers in a fiber bundle, for example.

2 Acterna OLP-55

1 INTRODUCTION

The “Auto λ” function provided by the OLP-55 Optical Power Meters allows automatic wavelength detection. Therefore a wavelength encoding light source is needed, e.g. the ACTERNA OLS-55 light sources.

Differences between the devicesAll of the power meters are calibrated at 850 nm, 1310 nm,1550 nm and 1625 nm. Differences between the devices can be found in the diode types and the maximum permitted power level:

Table 1 Differences between the devices.

Symbols used in this operating manual

Following symbols are used in this operating manual:

Type Diode type Max. power level

OLP-55/01 Germanium 20 dBm

OLP-55/02 InGaAs 15 dBm

OLP-55/03 filtered InGaAs 26 dBm

OLP-55/04 filtered InGaAs 30 dBm

Acterna OLP-55 3

1 INTRODUCTION

CAUTION

Caution

Follow the instructions carefully to avoid damage!

WARNING

Warning

Follow the instructions carefully to avoid damage or injury!

DANGER

Danger

Follow the instructions carefully to avoid damage or severe injury!

DANGER

High Voltage

Follow the instructions carefully to avoid damage or severe injury!

This safety instruction is given when high voltage causes the danger

WARNING

Laser

Follow the instructions carefully to avoid damage or injury!

This safety instruction is given when laser radiation causes the danger. Additional information is given to specify the laser class.

! Very important instruction

Follow carefully the advice, e.g.! Make sure that you protect yourself

and others from exposure to laser light.

4 Acterna OLP-55

1 INTRODUCTION

✓ Requirement

This requirement has to be checked first, e.g.✓ The system is switched on

⇒ Instruction

Here is your input requested, e.g.:⇒ Select mode

italics type face

Result

Result following an action, e.g.The page opens.

bold type face

Keys and display elements

Keys and display elements are marked in bold type face.

Acterna OLP-55 5

2 SAFETY INFORMATION


Proper usage

Laser safety

CAUTION

Non-compliant usage

Non-compliant usage can be hazardous to the user or damage the device itself.

! Please make sure the allowable ambient conditions are not violated!

! Also note the specified measurement range!

! Before powering up the device, always make sure that it is in proper working order.

WARNING

Dangerous laser radiation!

The maximum permitted power for the OLP-55 can be 1000 times stronger than the limit specified for Laser Safety Class 1!

Laser radiation can cause irreparable damage to the retina if allowed to enter the eye.

! When the system or test generator is switched on, never look directly into the output or into a connected optical fiber.

! Please heed the normal precautions for working with lasers and consider local regulations.

6 Acterna OLP-55


Battery Operation

SNT-121A AC Adapter/Charger

Safety class

The SNT-121A AC Adapter/Charger Unit is protectively isolated in conformance with IEC 60950.

Environmental conditions

WARNING

Explosion danger

Dry batteries can explode if you attempt to recharge them.

! Make sure to select Dry battery as battery type when using dry batteries and the SNT-121A AC Adapter/Charger.

Short-circuit of batteries can result in overheating, explosion or ignition of the batteries and their surroundings.

! Never short-circuit the battery contacts by touching both contacts simultaneously with a metal object.

CAUTION

Ambient temperature too high/low

Temperatures outside the operating range of 0 to +40 °C can damage the SNT-121A AC Adapter/Charger Unit or adversely affect its function and safety.

! The SNT-121A AC Adapter/Charger Unit must only be operated indoors.

! The SNT-121A AC Adapter/Charger Unit must only be operated at ambient temperatures between 0 and +40 °C.

Acterna OLP-55 7


CAUTION

Insufficient ventilation

Insufficient ventilation can damage the SNT-121A AC Adapter/Charger Unit or adversely affect its function and safety.

! Ensure adequate ventilation when operating the SNT-121A AC Adapter/Charger Unit.

CAUTION

Condensation

Operation in the presence of condensation can damage the SNT-121A AC Adapter/Charger Unit or adversely affect its function and safety.

! Do not operate the SNT-121A AC Adapter/Charger Unit if condensation has formed.

! If condensation cannot be avoided, such as when the SNT-121A AC Adapter/Charger Unit is cold and is moved to a warm room, wait until the SNT-121A AC Adapter/Charger Unit is dry before plugging it into the AC power line.

8 Acterna OLP-55

3 GETTING STARTED

3 GETTING STARTED

Unpacking the device

Packing materialWe suggest that you keep the original packing material. It is designed for reuse (unless it is damaged in transit). Using the original packing material is your guarantee of protecting the device during transit.

Checking the package contentsYour level meter is shipped with the following accessories:• 1 adapter (BN 2014/00.xx)• 4 dry batteries AA size• Belt bag MT-1S• Operating manual

Checking for damages in transitAfter you unpack the device, check to see whether it was damaged in transit. This is particularly likely if the packaging is clearly damaged. If there is damage, do not attempt to operate the device. Doing so can cause further damage.

Recovery following storage/transportCondensation can occur if a device that is stored or transported at a low temperature is brought into a warm room. To avoid damages, wait until no more condensation is visible on the surface before powering up the device. Do not operate the device until it has reached its guaranteed temperature range (-10 to +55 °C).The last statement also applies if the device is stored at a high temperature.

Acterna OLP-55 9

3 GETTING STARTED

Device overview

Fig. 1 OLP-55 front and side view.

3

4

5

1

2

6

7

Device label(on the back)

-----

----

10 Acterna OLP-55

3 GETTING STARTED

1 Test head cover

2 Test adapter

3 Display

4 Stand (back)

5 Power Supply socket, USB interface

6 Battery compartment (back)

7 Key pad

WavelengthSelect a wavelength from the list

BacklightActivate display backlight

PreviousStep one menu level backwards (without storing settings)

MENU/ENTER

• Open menu and select menu item• Store settings

Power On/OffSwitch unit on and off

Up/Down

• Scroll menu up/down• Change levels, wavelengths

STOREStore actual displayed values

dBm/WToggle level display between dBm and Watt

dBSelect relative level power measurement

Table 2 Device overview and key pad.

Acterna OLP-55 11

3 GETTING STARTED

Power Supply

The following power sources can be used to operate the OLP-55:• Four 1.5 V dry batteries (Mignon AA size, Alkaline type

recommended)• Four 1.2 V NiMH rechargeable batteries (Mignon AA

size)• The SNT-121A AC Adapter/Charger.• Via USB interface in remote operation.

Replacing batteriesThe battery compartment is on the back of the instrument.

Replacing the batteries

1. Open the battery compartment.2. Place in new batteries or remove the used batteries

with fresh ones.

Notice: Take care of the correct polarity of the batteries. It is indicated by a diagram on the floor of the battery compartment.

3. Close the battery compartment.After powering on the device you are asked in the BATTERY CHANGED menu to specify whether dry batteries or rechargeable batteries are used.

Fig. 2 Setup menu for battery type.

12 Acterna OLP-55

3 GETTING STARTED

Battery operation

Operation with dry batteries1. Insert batteries (see “Replacing batteries”, page 11)2. Select Dry battery in the

BATTERY CHANGED menu.

Note: When using the SNT-121A additionally the OLP-55 is supplied from the SNT-121A.

Operation with rechargeable batteries

1. Insert batteries (see “Replacing batteries”, page 11)2. Select Rechargeable in the BATTERY CHANGED

menu.

Recharging the batteries

When using the SNT-121A, and the battery capacity is lower 90%, the batteries are recharged (complete recharging takes about 3 hours). The instrument switches to trickle charging automatically as soon as the batteries are fully charged.

WARNING

Explosion danger

Dry batteries can explode if you attempt to recharge them.

! Make sure to select Dry battery as battery type when using dry batteries and the SNT-121A AC Adapter/Charger.

WARNING

Explosion danger

Short-circuit the batteries can result in overheating, explosion or ignition of the batteries and their surroundings.

! Never short-circuit the battery contacts by touching both contacts simultaneously with a metal object.

Acterna OLP-55 13

3 GETTING STARTED

If the charge cycle does not start although the Adapter/Charger is connected, please check the battery setup in the INFO menu.

Note: The battery type can not be selected by the instrument keys. To change the battery type the battery compartment must be opened and at least one battery must be removed for more than five seconds. After replacing the battery the OLP-55 asks for the battery type. The battery type you choose then will be stored until you change the batteries again.

General tips on using rechargeable batteries

• Always handle rechargeable batteries with care.• Do not drop or damage the rechargeable batteries or

expose them to excessively high temperatures.• Only recharge the batteries while they are fitted in the

OLP-55 and only use the SNT-121A AC Adapter/Charger for this purpose.

• Do not store the batteries for more than one or two days at very high temperatures (e.g. in a vehicle), either separately or fitted in the instrument.

• Do not leave discharged batteries in the instrument for a long time if it is not being used.

• Do not store rechargeable batteries for more than 6 months without discharging and recharging them at intervals.

• Avoid deep discharging the batteries as this can cause the cell polarity to reverse and make the battery useless.

Protect the environment

Please dispose of any unwanted dry batteries or rechargeable batteries carefully. They should therefore also be removed from the instrument if it is to be scrapped. If facilities in your country exist for collecting waste or for recycling, please make use of them rather than throwing the batteries in the normal trash. You will often be able to return used batteries to the place where you purchase new ones. Any dry or rechargeable batteries that you purchased from Acterna can be returned to one of our Service Centers for disposal.

14 Acterna OLP-55

3 GETTING STARTED

Operation from AC power

The OLP-55 can also be powered from the SNT-121A AC Adapter/Charger only if it is mainly to be used in one place, such as in a laboratory or test workshop. There is a socket on the side of the OLP-55 for plugging in the cable of the AC Adapter/Charger Unit.

Tip: The AC Adapter/Charger Unit provides power even if dry or rechargeable batteries are fitted in the instrument.

Fitting the AC line plug adapter

1. Select the appropriate AC line plug adapter.2. Slide the AC line plug adapter into the slot

(see Fig. 3).The SNT-121A AC Adapter/Charger is ready for use.

Fig. 3 SNT-121A AC Adapter/Charger

Changing the AC line plug adapter

1. Place the SNT-121A AC Adapter/Charger against the edge of a table or bench as shown (see Fig. 4).

2. Push the SNT-121A AC Adapter/Charger downwards.

3. Slide another AC line plug adapter into the slot (see Fig. 3).

Fig. 4 SNT-121A: Changing the AC line plug adapter

Acterna OLP-55 15

3 GETTING STARTED

Fitting adapters for plug connectors

The BN 2014/00.xx range of accessories includes a number of test adapters for connecting the OLP to the interface to be tested (connector or bare fiber).Using these adapters, you can connect all standard optical connector types to the instrument. The test adapters are suitable for connectors with planar (PC) and angled (APC) end surfaces.The “Ordering Information” section lists the available adapter types.

To fit adapters

1. Remove the protective dust cap.2. Place the test adapter on the jack and secure it by

tightening the knurled screws.

Fig. 5 Mounting the adapter.

CAUTION

Possible damage due to dirt or

scratching.

! When fitting the adapter be careful not to touch the photo diode.

16 Acterna OLP-55

4 OPERATION

4 OPERATION

Power ON/OFF

⇒ Press to power on the device.

⇒ Press for more than 2 sec. to power off the device.

The OLP-55 provides two power modes:• Permanent ON (PERM):

The device remains powered on• Automatic OFF (ECON):

The device powers off 20 min. after last operation. This function is available only in battery mode.

To change power mode

✓ The device is switched on.1. Press shortly (for less than 2 sec.).

The power mode EDIT menu opens:

Fig. 6 Power mode EDIT menu

2. Select Permanent ON or Automatic OFF.3. Press to set power mode.

The menu window closes.

Tip: To power off the device, you also can use the Power OFF item in this menu instead of pressing the button.

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4 OPERATION

Measurement Display

After the device is powered up, the measurement display is showed.

Fig. 7 Measurement display

External power supplyWhen symbol is shown the OLP-55 is powered by the external AC adapter

Battery statusShows actual battery status. If it is not shown, only the AC adapter is in use.

USB Power supply via USBIn remote operation the device is powered via the USB interface.

dBm Measured power levelDisplay of power level (Single Lambda Mode in this case) and unit (dB, dBm, Watt)

PERM Power mode

• PERM: device remains powered on• ECON: device powers off 20 min. after

last operation.

CW Signal Modulation

• CW: Continuous Wave• Auto λ: Auto wavelength detection• 270 Hz, 1 kHz, 2 kHz: modulated light

detected

1310nm WavelengthSelected wavelength is displayed here.

18 Acterna OLP-55

4 OPERATION

Main Menu

⇒ Press to open the MAIN menu.

Fig. 8 MAIN menu

To select an item

1. Press ▲▼ to mark the desired item2. Press to select it.

To leave menu without changes

⇒ Press

Store ABS -> REF Store actual measured power level as new reference level (see page 26).

Edit Ref. Level Edit selected reference level manually (see page 26).

Manage Memory Open Memory Menu to view and manage stored measurement results (see chapter 5, page 28).

Configuration Open Config. Menu (see page 19).

Acterna OLP-55 19

4 OPERATION

Configuration Menu

✓ MAIN menu is open⇒ Select Configuration

The CONFIGURATION menu opens

Fig. 9 CONFIGURATION menu

Edit λ-Table Edit the wavelengths in the table and the view status of each entry (see page 21).

Set Auto λ Enable/disable the Automatic Wavelength Detection - only available with Acterna OLS-55 (see page 23).

Edit Contrast Adjust display contrast (see page 20).

Set Factory default

Reset device to factory defaults. This has no impact on stored measurement results!

Show Info View device information: device name, family, serial number, calibration date, software version, battery type.

Edit DateEdit Time

Adjust date and time.

20 Acterna OLP-55

4 OPERATION

Basic settings

Display contrast⇒ Select Edit Contrast in the CONFIGURATION menu

The CONTRAST menu opens.

Fig. 10 CONTRAST menu

1. Press ▲▼ buttons to increase or decrease contrast2. Press to store value and leave menu.

Factory default1. Select Set Factory default in the CONFIGURATION

menu.The FACTORY DEFAULT menu opens.

Fig. 11 FACTORY DEFAULT menu

2. Press to set factory default– or –

Press to leave menu without changes.

Note: Setting the factory default does not impact your stored measurement results.

Acterna OLP-55 21

4 OPERATION

Backlight⇒ Press to switch backlight on/off.

Note: The backlight does not switch off automatically.

Selecting a wavelength

The OLP-55 allows to define up to ten wavelengths in a table (λ-Table). Only the wavelengths defined in this table and marked as shown can be selected for measurement.

To select a wavelength

⇒ Press to scroll through the table.The wavelength is shown in the left bottom display field.

Editing the λ-Table

The λ-Table allows to store ten user defined wavelengths. For each entry you can decide, whether it shall be displayed or not when scrolling through the list with the key (in measurement mode).By reducing the amount of showed entries the wavelengths can be faster recalled. So for example just two wavelengths could be displayed and toggled be one key press.

selected wavelength

22 Acterna OLP-55

4 OPERATION

To edit the λ-Table

1. Press Edit λ-Table in the CONFIGURATION menuThe EDIT λ-TABLE menu opens

2. Highlight the entry to be edited and press

3. Press again to edit selected wavelength (Edit is already selected)

4. Press ▲▼ to change value- press once to change step by step- hold key to accelerate count speed

5. Press to accept new wavelength.The EDIT λ-TABLE window is displayed again.

6. To change view status again press 7. Select Show to show wavelength in the table

– or –8. Select Hide to hide wavelength in the table 9. Press to accept selection.

⇒ Repeat steps 2. to 7. if needed.

Acterna OLP-55 23

4 OPERATION

Auto λ mode

Auto λ is a special feature invented by Acterna to identify wavelengths automatically. Therefor the signal is modulated (in a light source equipped with AUTO λ like the Acterna OLS-55/-56) by a certain frequency, which can be detected from the Acterna OLP-55.In following cases it may not be possible to detect wavelengths reliably:• The receive level is too low.• The wavelength encoding cannot be detected due to

interference.• You are measuring the absolute level of a system that

does not have wavelength encoding like Acterna’s power sources.

Switching Auto λ mode on/off

1. Select Auto λ in the CONFIGURATION menu.The AUTO λ menu is displayed.

2. Select ENABLE to switch on Auto λ– or –

Select DISABLE to switch off Auto λ.3. Press to accept setting.

When Auto λ mode was activated a laser source is connected supporting Auto λ, Auto λ will be displayed in the center bottom display field if.

24 Acterna OLP-55

4 OPERATION

Auto λ mode display

When Auto λ mode is activated and wavelengths are detected, the measured power levels are displayed simultaneously.

Fig. 12 Display in Auto λ mode showing the detected wavelengths and power levels.

Modulated lightThe OLP-55 automatically detects the modulation frequency of light signals modulated at the fixed frequencies: 270 Hz, 1 kHz and 2 kHz.The detected frequency is shown in the center bottom display field.

Fig. 13 Detection of modulated light, e.g. 270 Hz.

Acterna OLP-55 25

4 OPERATION

Display absolute power level

In the absolute power level mode the power level is displayed in dBm or Watt (nW, µW, mW).⇒ Press dBm/W to display absolute power level and to

toggle between dBm or Watt.

Fig. 14 Displaying absolute power level in dBm.

Power level ranges

Dark current adjustment (Auto-Zeroing)Dark current adjustment is not needed, as the OLP-55 provides a patented Auto-Zeroing function.

Tester dBm Watt

OLP-55/01 -70 to +20 dBm 0.1 nW to 100 mW

OLP-55/02 -80 to +15 dBm 0.01 nW to 32 mW

OLP-55/03 -60 to +26 dBm 1 nW to 400 mW

OLP-55/04 -60 to +30 dBm 1 nW to 1000 mW

26 Acterna OLP-55

4 OPERATION

Display relative power level

The relative power display mode shows the actual measured power level relatively to a reference value. This reference value can be set by defining the actual power level as reference value and can be edited manually.

Setting the reference level

✓ The device is in absolute power level display mode1. Press to open Main menu

2. Press again to store reference level.The actual power level is set as new reference level. The reference level is displayed in the top display bar. Reference power level display mode is activated.

Note: The reference level must be stored for each wavelength separately and will be saved during power off.

Editing the reference levelA reference level can be also edited manually.1. Select Edit Ref. Level in the MAIN menu

The measurement display opens, showing EDIT in the top right corner.

2. Press ▲▼ to change value3. Press to accept setting.

Acterna OLP-55 27

4 OPERATION

Maintenance

Cleaning the test portOver time, dust can gather on the photo diode, particularly if you leave the cover open for a while or remove the adapter.To retain high measurement accuracy, we recommend that you clean the photo diode from time to time.

1. Pop open the cover on the front of the OLP.2. Unscrew the adapter by hand.

You can now access the photo diode.

3. Use a cotton swab dipped in isopropanol to wipe off the photo diode. This is an effective cleaning method that leaves no traces.

4. Blow off the test adapter with pressurized air (e.g. anti-dust spray available in cans).

5. Screw the adapter back on.6. Pop the cover back on.

Tip: To avoid premature soiling of the assembly, keep the adapter in place and the cover closed when you are not making measurements.

Cleaning the instrumentIf the instrument has become dirty through use, it can be cleaned using a soft cloth moistened with a mild solution of detergent.

Parts which have become very dirty may also be cleaned carefully using alcohol.

CAUTION

Damage of photo diode

! Do not touch the photo diode in order to avoid soiling or scratching the glass cover.

CAUTION

Damage of device

! Make sure that the cleaning solution does not get inside the instrument.

28 Acterna OLP-55

5 MEMORY MANAGEMENT

5 MEMORY

MANAGEMENT

General Information

The OLP allows you to save the measured level values in a structured data memory and recall them as required. Up to 350 results can be stored. All data is saved to a non-volatile memory (E2PROM).Data can also be downloaded via the USB interface to a PC for further evaluation.Two methods of recording values are available to meet individual requirements:• Measured values stored in successive memory

positions.• Measured values stored in pre-defined memory

positions.

Result memory structureThe OLP-55 is equipped with a data memory which is structured according to the typical device under test, i.e. a cable made up from several fibers. This hierarchical structure predetermines the memory positions which are generally made up from the following data: • Group number: 001 to 350• Meas(urement) number: 001 to 350• WavelengthA combination of these three values is assigned to each memory position with each value being separately accessible.

Acterna OLP-55 29

5 MEMORY MANAGEMENT

Saving results successively

Results are stored simply by pressing the STORE key. Each time the key is pressed, the next memory position will be used to store the current result. If the memory is initially empty, memory begins with Group 001 and Meas 001. The Meas # is then incremented each time the key is pressed (up to a maximum of 350).This method is ideal for simple measurement sequences, e.g. when a limited number of level values for a single item under test is to be recorded.

To save current results successively

✓ The complete result memory is empty or the first and following memory positions are empty.

✓ The device is in measure mode.

1. Press the STORE key to save the first result.The display briefly indicates the first memory position, i.e. Group 033, Meas 001.

Fig. 15 Brief display of memory position confirms that first result value has been saved

2. Press the STORE key again every time you want to save a further result value.The display briefly shows the memory position used. The Meas # will be incremented each time.

If the results are to be stored starting from a different memory position such as Group 015, Meas 005, these values must be specified in advance (see “Saving results at a selected position”, page 32).

30 Acterna OLP-55

5 MEMORY MANAGEMENT

If you try storing data on memory positions that have been already occupied by the results of previous measurements, a warning will be displayed:

Fig. 16 Display if selected memory position is already occupied.

⇒ Press to overwrite data with new data.

⇒ Press if you do not want to overwrite existing data.

Displaying stored results

Displaying your last stored measurement results will surely be the function mostly used. Thus this memory position will be displayed when entering the MANAGE MEMORY menu. As default the Meas # is highlighted to allow quick access to all measurements of a fixed Group.

Displaying the last stored results

⇒ Select Manage Memory in the MAIN menuThe last stored results are displayed.

Fig. 17 Example for stored results: Group 025, Meas 004: 3 wavelengths detected, relative measurement mode with measured levels and reference values.

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5 MEMORY MANAGEMENT

Select another Measurement of actual Group

⇒ Press ▲▼ keys to increase/decrease Meas #.

Fig. 18 Display of stored results, select Meas #.

Select another Group and Measurement

1. Press The MANAGE MEMORY menu opens,

2. Press to select Select Group.Actual Group and Meas 001 will be displayed.

3. Press ▲▼ keys to increase/decrease Group #.4. Press

MEAS # will be highlighted

5. Press ▲▼ keys to increase/decrease Meas # .

⇒ Press to leave menu.

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5 MEMORY MANAGEMENT

Saving results at a selected position

When pressing the STORE key in measurement mode the results are stored at the active memory position. Each press increments the Meas # at a fixed Group. In measurement mode you can not set the memory position, neither the Meas nor the Group number.If you do not want to overwrite existing data or if you want to set a specific Group and Meas number, you must enter the MANAGE MEMORY menu and select the position.This is identical to display a memory position (see “Displaying stored results”, page 30), as the last displayed memory position always becomes the actual memory position when storing data.

To save results at a selected position

1. Set wavelength and measurement mode as needed.2. Select Manage Memory in the MAIN menu.3. Press ▲▼ keys to edit Meas # only.

If you just want to edit Meas # proceed with step 9.

4. Press The MANAGE MEMORY menu opens.

5. Press again (Select Group is highlighted)Actual Group # and Meas 001 are displayed.

6. Press ▲▼ keys to edit Group-Nr.7. Press

Meas # is highlighted8. Press ▲▼ keys to edit Meas #.9. Press to leave menu.

⇒ Press STORE to store results.

Acterna OLP-55 33

5 MEMORY MANAGEMENT

Clearing the memory

The OLP-55 allows to store 350 data sets with up to 3 measurement in Multi λ mode (together with Acterna OLS-55 light source). A data set consists of the wavelength, relative power level and reference value or absolute power level and date/time when it was stored.Even there may be no need to clear the complete memory because of missing capacity you may clear single Meas or Group positions to have access to specific numbers. The OLP-55 allows to clear• Clear Actual Meas

Clear data of selected measurement• Clear Group

Clear all measurements of the selected Group• Clear All

Clear all memory data

To clear memory data1. Select Manage Memory in the MAIN menu

The last stored results are displayed

2. Press to open the MANAGE MEMORY menu.

Fig. 19 MANAGE MEMORY menu

Clearing data of actual measurement:

1. Set Group and Meas number to be cleared (see page 32f)

2. Press ▲▼ keys to select Clear Actual Meas

3. Press to clear actual Meas data

4. Press to leave menu

34 Acterna OLP-55

5 MEMORY MANAGEMENT

When now storing results, memory position will be at the cleared Meas number of the last displayed Group.

Clearing all data of a Group

1. Set Group number to be cleared.2. Press ▲▼ keys to select Clear Group.

3. Press to clear all Meas data of the selected Group #.

4. Press key to leave menu.When now storing results, memory position will be at Meas 001 of last displayed Group.

To clear memory

1. Press ▲▼ keys to select Clear All.

2. Press to clear all memory data.

3. Press key to leave menu.When now storing results, memory position will be at Group 001 and Meas 001.

Read out the result memory

All results stored in the memory can be read out via the USB interface to a PC for further evaluation or print out.INF file (Windows 2000 and XP) can be downloaded from www.acterna.com.

Acterna OLP-55 35

6 REMOTE CONTROL

6 REMOTE CONTROL

Communication interface

The OLP-55 provides a USB interface for communication.INF file (Windows 2000 and XP) can be downloaded from www.acterna.com.

Key

These are the adjustable values for the remote control commands.

Key

<STRING RESPONSE_DATA>: IEEE4888.2, 8.7.1

Not A Number (NAN)Not a number is represented as 9.91 E 37. Not a number is defined in IEEE 754. Typical applications are dividing zero by zero or subtracting infinity from infinity. Not a number is also used to represent missing data.

<NR1> Integer value. Examples 23 90<NR2> Real number. Examples 23.45 1.225<NR3> Exponential number.

Examples 4.3E-3 -8.9456E8 123E-5<NRf> <NR1> | <NR2> | <NR3>

36 Acterna OLP-55

6 REMOTE CONTROL

<contrast> • contrast of display <NR1> | MINimum | MAXimum | DEFault

• MINimum 0 • MAXimum 20 • DEFault 10

<pow_refval> • reference value of power meter <NRf> | MINimum | MAXimum | DEFault

• MINimum -60 dBm• MAXimum 30 dBm• DEFault 0 dBm• suffix dBm• fundamental unit dBm

<powrange> • power meter measurement <NR1> | MINimum | MAXimum | DEFault

• MINimum 1• MAXimum 5• DEFault 3

<group_id> • group identifier <NR1> | MINimum | MAXimum | DEFault


<meas_id> • meas identifier for storing, deleting or recalling measurements to or from memory

• <NR1> | MINimum | MAXimum | DEFault


<wavval> • wavelength <NRf> | MINimum | MAXimum | DEFault

• MINimum 780• MAXimum 1650• DEFault 1550 • suffix m | mm | µm | nm• fundamental unit nm

Acterna OLP-55 37

6 REMOTE CONTROL

Parameters

Non-Instrument Mode commands

Command string

Parameter type / Response type / Unit / Info

DISP:CONT

Parameter type: <contrast>

Sets the display contrastRange 0 ... 15(0: min, 15: max.)

DISP:CONT?

Returns the display contrastRange 0 ... 15(0: min, 15: max.)

SYST:CAL:WAV:

<wav> selects the calibration wavelength from the λ-Table. See SYST:CAL:WAV:TAB? for more details.

e.g. SYST:CAL:WAV 850

SYST:CAL:WAV?

Returns the calibration wavelength currently used in the instrument.

SYST:CAL:WAV:TAB

Sets 10 wavelengths in the λ-Table. The wavelengths must be entered in order of increasing values.

e.g. SYST:CAL:WAV:TAB 820,850,980,1280,1300,1310,1480,1510,1550,1625

38 Acterna OLP-55

6 REMOTE CONTROL

SYST:CAL:WAV:TAB?

Returns the contents of the λ-Table.

SYST:ERR?

Response type: <NR1>,<STRING RESPONSE_DATA>

Returns the oldest error in the error queue,

e.g. -100, “Command error"

SYST:PERM:POW

Ensures the device is on permanently i.e. that it does not power down after 20 minutes

Command string


Acterna OLP-55 39

6 REMOTE CONTROL

Power Meter

Command string


DISP:UNIT

Parameter type: LIN | LOG

Selects whether power level reading is displayed linearly or logarithmically.

LIN: linear display of power levelLOG: logarithmic display of power level

DISP:UNIT?

Response type: LIN | LOG

Returns whether power level reading is displayed linearly or logarithmically:

LIN: linear display of powerLOG: logarithmic display of power

FETC:AM:AUTO:FREQ?

Returns whether an “Auto λ”modulation frequency detected on the incoming.

0: Auto λ modulationfrequency detected

1: no Auto λ modulationfrequency detected

FETC:AM:INT:FREQ?

Response type: <NR2>

Unit: Hz

Returns the modulation frequency on the incoming signal

40 Acterna OLP-55

6 REMOTE CONTROL

FETC:POW:INP?


Unit: dBm, W, dB

Returns the power at the input port of the device.

Response:

Absolute display (:REF:STAT 0)- in dBm for DISP:UNIT LOG- in W for DISP:UNIT LIN

Relative display (REF:STAT 1) in dB

+9.91E37 overflow-9.91E37 underflow

MEM:DEL:ALL

Deletes the entire measurement results memory.

MEM:DEL:GROU

Deletes the measurement in the group specified by <NR1>

1 ≤<NR1> ≤1000

MEM:DEL:MEAS

Deletes the current measurement. If command is repeated, the next measurement is deleted.

MEM:FREE?

Returns number of how many measurements can still be stored until memory is full.

MEM:GROU

Selects the group in which measurement is stored, deleted or recalled.

1 ≤ <NR1> ≤350

MEM:GROU?

Returns the group in which measurement is stored, deleted or recalled.

1 ≤ <NR1> ≤350

Command string


Acterna OLP-55 41

6 REMOTE CONTROL

MEM:GROUMEAS

Sets the measurement number within the current group at which the measurement is stored, deleted or recalled.

1 ≤ <NR1> ≤350

MEM:GROUMEAS?

Returns the measurement number within the current group at which the measurement is stored, deleted or recalled.

1 ≤ <NR1> ≤350

MEM:IDMEAS?

Returns the current group and measurement number at which the measurement is stored, deleted or recalled.

Return value: <group>,<offset>

MEM:REC:ALL?

Recalls all the measurement stored in EEPROM at the current group/index value.

For each measurement<group>, <meas>,<time>, <date>, <measdata> [;<measdata.]

MEM:REC:MEAS?

Recalls the measurement stored in EEPROM at the current group/meas value.

<group>, <offs>,<time>, <date>, <measdata> [;<measdata.]

Command string


42 Acterna OLP-55

6 REMOTE CONTROL

MEM:STOR:MEAS

Stores the current measurement under the current group/measurement number selected.

NOTE: If this command is repeated immediately (i.e. with no other commands, such as MEM:REC:MEAS? in between), the identifier is subsequently incremented by 1 for the next store.

REF:STAT

Parameter type: <BOOLEAN>

Determines whether power level reading is displayed as an absolute or relative value.

0: absolute value1: relative value

Default setting: 0

REF:STAT?


Returns how the power reading is displayed

0: absolute value1: relative value

REF:VAL

Parameter type: <pow_refval>ABS

Sets the value which the power level reading refers to in relative mode where:

• <pow_refval> is the floating point value of the required reference value or

• ABS: reference value = absolute power level value.

Default setting: 0 dBm

Command string


Acterna OLP-55 43

6 REMOTE CONTROL

REF:VAL?


Unit: dBm

Returns the value which the power level reading refers to in relative mode.

WAV:AUTO

Parameter type: <BOOLEAN>

Determines whether device recognizes Auto λ modulation frequencies which automatically sets the system calibration wavelength.

0: Auto λ recognition off1: Auto λ recognition on

Default setting: 0

WAV:AUTO?

Returns whether Auto-λ recognition on or off

0: Auto λ detection off1: Auto λ detection on

SYST:DATE

Sets the date (yy,mm,dd)

e.g. 04,10,21

SYST:DATE?

Returns the date (yy,mm,dd)

e.g. 04,10,21

SYST:TIME

Sets the time (hh:mm:ss)

e.g. 16.01 h is set by 16,01,00

Note: 24 h system is used: 16.01 h means 4.01 pm.

SYST:TIME?

Returns the time (hh:mm:ss)

e.g. 16,01,00

Command string


44 Acterna OLP-55

7 MEASUREMENT EXAMPLE

7 MEASUREMENT

EXAMPLE

Example: Attenuation measurement

The optical attenuation of cable # 3 containing a total of 6 fibers (1310 nm) is to be measured as per IEC 874-1, Method 6.The first step is to make a reference measurement at point A. The second step measures the loss due to the fiber path at point B.

Fig. 20 Item under test: Cable 3, fibers 1 to 6

Test equipment

• OLP-55 Optical Power Meter• OLS-55 Optical Laser Source• 1 test adapter, BN 2014/00.xx• 2 adapter cables, K 31xx (9/125 µm)• 2 adapters, S 31xx• 1 test adapter, BN 2150/00.xx

Acterna OLP-55 45


Step 1: Reference measurement

Fig. 21 Test setup for ref. measurement at point A

Test procedure at point A

1. Fit the OLP and OLS with test adapters.2. Fit the OLP and OLS with one adapter cable each and

link them together using the S 31xx adapter.3. Set the OLS and OLP to 1310 nm4. Set the OLS to CW mode.5. Set the OLP to absolute level display mode.6. Save the measured level as reference level (ABS ->

REF).7. Set the OLP to relative level display mode.8. Leave cable K 31xx at OLS and OLP connected

during the complete attenuation measurement.9. Connect the OLS with cable K 31xx at point A to the

item under test (cable 3, fiber 2).10.Move the OLP to point B.

46 Acterna OLP-55


Step 2: Att. measurement

Fig. 22 Test setup for measuring attenuation

Test procedure at point B

⇒ Connect the OLP at point B with the item under test (cable 3, fiber 2).The insertion loss for fiber 2 will be displayed.

Step 3: Saving the results⇒ Press Store

The measured value will be stored at the memory location defined in the MANAGE MEMORY menu:– Memory location is not yet occupied: Storing...

shows the successful process.– Memory location is already occupied:

You will be asked to overwrite data.For further information how to store measurement results at a specific memory position please see “Saving results at a selected position”, page 32.

Acterna OLP-55 47

8 SPECIFICATIONS

8 SPECIFICATIONS

BN 2277/01

Adjustable wavelength range

780 to 1650 nm,in 1 nm steps

Calibrated wavelengths

850 nm, 1310 nm,1550 nm, 1625 nm

Photo diode GermaniumFiber type 9/125 to 100/140Display range -70 to +20 dBmResolution1) 0.01 dB, 0.001 µWMax. permitted level +20 dBmIntrinsic uncertainty2) ± 0.13 dB (± 3%)Overall measurement uncertainty850 nm1300, 1310 nm1550 nm1625 nm3)

-60 to +18 dBm

± 0.25 dB ± 0.8 nW± 0.20 dB ± 0.2 nW± 0.40 dB ± 0.2 nW± 0.60 dB ± 0.6 nW

1) For levels < -60 dBm: 0.1 dB2) Under reference conditions: -20 dBm (CW), 1310 nm ±1 nm,

23 °C ±3K, 45 to 75% relative humidity, 9 to 50 µm test fiber with DIN connector

3) Under reference conditions: -20dBm (CW), 1625 nm ±1 nm, 23 °C ±3K, 45 to 75% relative humidity, 9 µm test fiber with DIN connector

48 Acterna OLP-55

8 SPECIFICATIONS

BN 2277/02




850 nm, 1310 nm,1550 nm, 1625 nm

Photo diode InGaAsFiber type 9/125 to 50/125Display range -80 to +15 dBmResolution1) 0.01 dB, 0.001 µWMax. permitted level +15 dBmIntrinsic uncertainty2) ± 0.13 dB (± 3%)Overall measurement uncertainty850 nm1300, 1310 nm1550 nm1625 nm3)

-70 to +11 dBm

± 0.3 dB ± 0.15 nW± 0.2 dB ± 0.02 nW± 0.2 dB ± 0.02 nW± 0.4 dB ± 0.02 nW

1) For levels < -70 dBm: 0.1 dB2) Under reference conditions: -20 dBm (CW), 1310 nm ±1 nm,

23 °C ±3K, 45 to 75% relative humidity, 9 to 50 µm test fiber with DIN connector.

3) Under reference conditions: -20 dBm (CW), 1625 nm ±1 nm, 23 °C ±3K, 45 to 75% relative humidity, 9 µm test fiber with DIN connector.

Acterna OLP-55 49

8 SPECIFICATIONS

BN 2277/03




850 nm, 1310 nm,1550 nm, 1625 nm

Photo diode filtered InGaAsFiber type 9/125 to 50/125Display range -60 to +26 dBmResolution1) 0.01 dB, 0.001 µWMax. permitted level +26 dBmIntrinsic uncertainty2) ± 0.13 dB (± 3%)Overall measurement uncertainty850 nm1300, 1310 nm1550 nm1625 nm3)

-47 to +26 dBm

± 0.33 dB ± 25 nW± 0.25 dB ± 4 nW± 0.25 dB ± 4 nW

± 0.5 dB ± 4 nW1) For levels < -50 dBm: 0.1 dB2) Under reference conditions: -20 dBm (CW), 1310 nm ±1 nm,


3) Under reference conditions: -20dBm(CW), 1625 nm ±1 nm, 23 °C ±3K, 45 to 75% relative humidity, 9 µm test fiber with DIN connector.

50 Acterna OLP-55

8 SPECIFICATIONS

BN 2277/04




850 nm, 1310 nm,1550 nm, 1625 nm

Photo diode filtered InGaAsFiber type 9/125 to 50/125Display range -60 to +30 dBmResolution1) 0.01 dB, 0.001 µWMax. permitted level +30 dBmIntrinsic uncertainty2) ± 0.13 dB (± 3%)Overall measurement uncertainty850 nm1300, 1310 nm1550 nm1625 nm3)

-47 to +30 dBm

± 0.33 dB ± 25 nW± 0.25 dB ± 4 nW± 0.25 dB ± 4 nW

± 0.5 dB ± 4 nW1) For levels < -50 dBm: 0.1 dB2) Under reference conditions: -20 dBm (CW), 1310 nm ±1 nm,


3) Under reference conditions: -20 dBm (CW), 1625 nm ±1 nm, 23 °C ±3K, 45 to 75% relative humidity, 9 µm test fiber with DIN connector.

Acterna OLP-55 51

8 SPECIFICATIONS

General specifications

Display

Memory

Wavelength detection1)

Automatic switching and displaying upto three wavelengths simultaneously

Referencelevel

Transfer of measured value or entry ofany reference level

in the range -80 to +30 dBm,one Reference Level for

each wavelengthModulationdetection2)

270 Hz, 1 kHz, 2 kHz

Optical adapter system

Interchangeable adapter from BN2014/00.X range, suitable for PC and APC

systems1) Only together with Acterna OLS-55 Optical Light Sources.

Only works when power difference is < 20 dB.2) BN 2277/01: from -45 dBm (780 to 1299 nm),

from -50 dBm (1300 to 1625 nm), BN 2277/02: from -55 dBm (850 to 1299 nm), from -60 dBm (1300 to 1625 nm)BN 2277/03/04: from -32 dBm (850 to 1299 nm), from -37 dBm (1300 to 1625 nm)

Display type Graphical display,64 x 128, b/w.

backlight function

Memory capacity 1000 measurement resultsData readout/Remote control

via USB interface (INF filefor Windows 2000 and XP

included)

52 Acterna OLP-55

8 SPECIFICATIONS

Power supply

Ambient temperature

Air humidity

Occasional condensation is tolerable as a limit condition.

Dimensions and weight

Dry batteries 4 x AA, 1.5 VRechargeable batteries

NiCd, NiMH,4 x AA, 1.2 V

Operating life dry/rechargeable batteries typ. 100 hAC line operation with separate

AC adapterPower saving mode auto power-off after appr.

20 min(can be disabled)

Electromagnetic compatibility (EMC)

IEC 61321

Recommended calibration interval

3 years

Nominal range of useBN 2277/01/02BN 2277/03BN 2277/04

-10 to +55 °C-10 to +45 °C-10 to +40 °C

Storage and transport -40 to +70 °CSNT-121A AC Adapter/Charger

0 to +40 °C

Relative humidity up to +30 °C 5 to 95%Absolute humidity, > +30 °C 1 to 29 g/m3

Dimensions (w x h x d) 95 x 60 x 190 mmWeight approx. 500 g

(including batteries)

Acterna OLP-55 53

9 ORDERING INFORMATION

9 ORDERING

INFORMATION

Accessories

OLP-55/01 Optical Power Meter BN 2277/01




Calibration report BN 2277/90.03

Optical adapter BN 2014/00.xxOCK-10 Optical cleaning kit BN 2229/90.21Cleaning tape for optical connectors BN 2229/90.07Spare tape for optical cleaning tape BN 2229/90.08

NiMh cells (AA size, 1.2 V) BN 2237/90.02SNT-121A AC Adapter/Charger(worldwide compatible)

BN 2277/90.01

Belt bag MT-1S BN 2277/90.02Soft case 2 instruments MT-2S BN 2126/03Soft case 3 instruments MT-3S BN 2126/04Hard case 3 instruments MK-3S BN 2093/31

Acterna OLP-55

Index

Index

A

AC line plug adapter 14Accessories 53Attenuation measurement 46Auto lambda mode 23Auto-Zeroing 25

B

BatteriesOperation 12Recharging 12Replacing 11

Battery Operation 6

C

CleaningInstrument 27Test port 27

Clearing the memory 33Common features 1Condensation 8Contrast 20

D

Dark current adjustment 25Data memory 28Default 20Device overview 9Differences between the de-vices 2Display 17Display contrast 20

E

E2PROM 28Environmental protection 13

F

Factory default 20

I

IEC 874-1 44Insertion loss 46

L

Lambda-Tableedit 21

Laser safety 5

M

Measurement display 17Memory position 32Memory structure 28Menu

Configuration 19Main 18

Modulated light 24

N

NAN 35Not A Number 35

O

Operation from AC power 14Overview 9

P

Package contents 8Packing material 8Plug connector 15Power

change mode 16ON/OFF 16

Power levelAbsolute 25Relative 26

Power level ranges 25Power mode 16Proper usage 5

R

Rechargeable batteries 13Recovery 8Recycling 13Reference measurement 45Results 29

S

Saving results 29SNT-121A

Environmental conditions 6Safety class 6

SNT-121A AC Adapter/Charger Unit 14

T

Test equipment 44Test procedure 45

Acterna Environmental Management Program

Superb performance and high quality have always characterized Acterna datacom and telecom measurement technology prod-ucts. In this same world-class tradition, Acterna has an estab-lished, proactive program of environmental management.

Environmental management is an integral part of Acterna’s busi-ness philosophy and strategy requiring the development of long-term, productive solutions to problems in the key areas of eco-nomics, technology, and ecology.

A systematic environmental management program at Acterna is essential in regard to environmental policy and enhances cooper-ation between ourselves and our business partners.

The Acterna Environmental Management Program considers:

Product design and manufactureEnvironmental restrictions and requirements are taken into account during planning and manufacture of Acterna products. This attention ranges form the raw materials and finished compo-nents selected for use and the manufacturing processes employed, through to the use of energy in the factory, and right on up to the final stages in the life of a product, including disman-tling.

Hazardous materialsActerna avoids or uses with care any hazardous or dangerous material in themanufacturing process or the end product. If the use of a dangerous material cannot be avoided, it is identified in product documentation and clearly labeled on the product itself.

Packaging materialsPreference is given to reusable or biodegradable single-sub-stance packaging materials whenever possible.

Environmental management partnershipsActerna encourages our customers and suppliers who take this responsibility seriously to join Acterna in establishing their own environmental management programs.

Recycling used productsActerna has an effective program for the recycling and/or dis-posal of used equipment. Our customers in Germany can already take advantage of our return service for used instruments. In Europe, all new equipment purchased from Acterna can be returned for scrapping at the end of its useful life, free of charge.

If you would like specific information about the Acterna Environ-mental Management Program, please contact us at:

GermanyEnvironmental Management:Tel. +49-(0)7121 86 1470Fax +49-(0)7121 86 1502

United KingdomDesign Office:Tel. +44-1752 772 773Fax +44-1752 709 897

United StatesEnvironmental Management:Tel. +1-919 941 5730Fax +1-919 941 5751

FranceEnvironmental Management:Tel. +33-(0)2 99 84 70 40Fax +33-(0)2 99 84 70 44

Worldwide Headquarters

12410 Milestone Center DriveGermantown, Maryland20876-7100USA

Acterna is present in more than 80 countries. To find your local sales office go to: www.acterna.com

Regional Sales Headquarters

North America12410 Milestone Center DriveGermantown, Maryland20876-7100USAToll Free +1 866 ACTERNAToll Free +1 866 228 3762Tel. +1 301 353 1560 x 2850Fax +1 301 353 9216

Latin AmericaAv. Eng. Luis Carlos Berrini936/8o e 9o andares04571-000 São PauloSP-BrasilTel. +55 11 5503 3800Fax +55 11 5505 1598

Asia/Pacific42 Clarendon StreetPO Box 141South MelbourneVictoria 3205AustraliaTel. +61 3 9690 6700Fax +61 3 9690 6750

Western EuropeArbachtalstraße 672800 Eningen u.A.GermanyTel. +49 7121 86 2222Fax +49 7121 86 1222

Eastern Europe, Middle East & AfricaAredstrasse 16-182544 LeobersdorfAustriaTel. +43 2256 65610Fax +43 2256 65610-22

Prospect Mira 26, stroenie 5 RF 129090 Moscow RussiaTel. +7 095 937 88 04Tel. +7 095 775 26 04Tel. +7 095 775 26 07Tel. +7 095 775 26 08Fax +7 095 775 26 05

Notes:

OLP-55

Documents

121a ac adaptercharger

original packing

dark current

bold type

mignon aa

ac adaptercharger

battery changed

manage memory