GAOTek Two Wavelength Optical Light Source with Power Meter

This Optical Light Source with Power Meter

provides a modulated light which is used in determining the

amount of loss in an optical fiber cable and comes with 1310 nm/1550 nm

wavelength options.




The GAOTek Two Wavelength Optical Light Source with Power Meter is used as an optical fiber light source and, along with an optical meter, can determine the loss of an optical fiber cable. This device provides two wavelength outputs (1310 nm/1550 nm wavelength) for single-mode fiber. This device comes with a battery life of 60 hours. It is widely used in the field of cable construction and maintenance, optical fiber transmission, optical fiber communication, fiber optical sensors, and CATV.

Key Features

  • Provides two wavelength output: 1310 nm, 1550 nm, which can be selected according to customer’s needs
  • CW: 0 Hz modulation output at 650 nm, and CW: 270 Hz, 1 KHz, 2 KHz modulation output at other wavelengths
  • High stability output power
  • FC/SC/ST general-purpose interface
  • Battery serving time is 60 hours
  • Compact, portable and user-friendly
  • Large LCD, ease of operation with LCD backlight
  • Auto-off function (15 min)

Technical Specifications

Wavelength 1310 nm, 1550 nm
Emitter Type FP-LD
Modulation Frequencies CW/2 Hz (650)/270 Hz, 1 KHz, 2 KHz
Fiber Type SM, MM
Output Stability ±0.04 dBm @20 ℃ @15 min
Operating Temperature 14 °F to 140 °F (-10 ℃ to 60 ℃)
Storage Temperature -13 °F to 158 °F (-25 ℃ to 70 ℃)
Automatic Shutdown Time 15 min
Battery Serving Time 60 h
Overall Dimension 7.28 in x 4.13 in x 1.96 in (185 mm × 105 mm × 50 mm)
Power Supply 9 V battery, AC adapter
Weight 0.77 lbs (350 g)

Additional Information

Functional Description

1.   Press button to startup and shutdown

2.   Auto-off function: The unit will turn off after 15 mins if non-operational.

3.   Backlight: The backlight is on when the tester is turned on and when any key is pressed. The backlight times out after approximately 30 seconds of inactivity to conserve battery cover.

Description of Front Panel keys

1.   Power Key :

  • This key is used to turn on the tester, pressing it for 2 s continuously will cause the meter to get turned off.
  • Auto-off function selection: This key can be used to activate or shut down the Auto-off function. In addition, if there is no operation for over 15 mins, the power meter will shut off automatically.

2.   Wave key

This key is used for wavelength selection.

3.   Mode key

Modulation control output and modulated light output can be selected by pushing the Mode key. When modulated light output is selected, a dot appears in LCD.

Description of the Information on LCD

After pressing power key to start the meter, the following information will be shown on LCD:

  1. If the meter is supplied by battery, the icon   at the left bottom will be ON. With the reduction of electric amount of battery, the display segment of battery becomes less and less till empty.
  2. When connected with an AC adapter, an icon will be lit at the middle of screen, at the same time, the electric amount icon will turn ON as well.
  3. At the left lower position, it is an “Auto-off” icon. After start, the Auto-off function is activated simultaneously and the icon is lightened as well, but if there is no operation, the meter will shut down 15 mins later.
  4. At the middle display-area of the screen, the value of wavelength will be displayed, the unit is nm.
  5. At right upper display-area of screen, shows reference frequency value, the unit is Hz.


  1. Connect the tested bridle wire to light source and power meter as shown in the following figure:
  2. Turn on the light source to enter working mode and press the wave key to select the wavelength to be tested.
  3. Press the mode key , choose the 0 Hz, 270 Hz, 1 KHz or 2 KHz light output.
  4. Turn on the fiber power meter and select specified wavelength.
  5. Press the power key to turn the tester off.


  • If not in use for a long time, please take out the battery.
  • If the Handheld Light Source is not used for a long time, the light output port must be protected with the dustproof cover.
  • Do not look into Handheld Light Source adapters directly when light source is on, as the laser output can cause harm to your eyes.


As a high sensitive electrical and optical instrument, this optical power meter must be maintained carefully so as to acquire high precision and flexibility. So, please pay close attention to the following points:

  • Before use, clean the optical fiber connector all the time
  • Keep it away from dust
  • Only store this instrument in a dry and clean place and keep away from direct sunshine.
  • Avoid high temperatures or large temperature variation.
  • Keep away from unnecessary impact or vibration.
  • If any liquid is splashed onto the surface or the inner part of the instrument, cut off the power supply and restart it only after drying completely.

Cleaning the Probe

Clean the probe of optical power meter regularly.

  1. Open the dustproof cap
  2. Screw off the adapter of power meter
  3. Use 0.09 in (2.5 mm) special cotton swab with some anhydrous alcohol to clean the surface of the probe slightly.

WARNING: when cleaning the probe of optical power meter, it is forbidden to use any hard object to touch the surface of the probe in case damage is caused to the probe. In addition, keep away from strong force to avoid cracking of the probe. Otherwise, the accuracy of the measurement value will be reduced, and could even lead to failure to carry out any measurement.

ATTENTION: when the optical power meter is not operated, cover using the dust-cap to keep the optical power meter clean.

9 V Battery Replacement

Open the back cover to install or take out the battery. When installing or taking out the battery, the following information may be helpful for your operation:

  • When the battery energy is lower or no 9 V battery installed, an icon will be displayed on the screen.
  • Only a suitable 9 V battery can be engaged
  • If not in use for a long time, take out the 9 V battery as it may cause corrosion and damage to internal components.

Calibration and Measurement

Under proper conditions, if this meter is used in a right way, a better performance can be guaranteed. In order to guarantee the performance, it is strongly suggested that one calibration per year should be implemented. If there is deviation, please calibrate it again.


Common Faults Possible Reason Solution
Inaccurate measurement of result Mismatch wavelength of light source Check that the correct wavelength has been selected
Unable to start or no screen display Inadequate 9 V Battery Replace with new battery
Dim LCD display Inadequate battery Use power adaptor or change the battery
Some variation of optical power of light source No preheating for optical meter Turn on the light source and activate the operating wave -length, then carry out measurement after 30 min pre-heating
Lower output power of light source Unclean connectivity port of light source Clean the connectivity port completely

Standard Configuration

  • Handheld light source – 1 pc
  • Operation Manual – 1 pc
  • AC Adapter – 1 pc
  • 9 V battery – 1 pc
  • Cotton swab – 1 pc
  • Tool kit – 1 pc