======FFC-100 Fiber Frequency Comb Quick Start Guide======

Model No. FFC-100-100 and FFC-100-200\\
Document Last Updated on ~~LASTMOD~~

Please read [[:limited_warranty|Limited Warranty]] and [[:warnings_cautions|General Warnings and Cautions]] prior to operating the FFC-100.

{{d2:d2-100:class_iiib.png?nolink&200}}
<imgcaption ffc|The FFC-100 Fiber Frequency Comb>{{ ffc:ffc_front_250_kb.png?350|}}</imgcaption>

====Useful Links====
Click here for the [[http://www.vescent.com/manuals/doku.php?id=manuals|Vescent manuals page]].\\
Click here for the [[ffc:100:api|FFC-100 API]].\\
Click here for the [[ffc:locking_electronics:slice-fpga|SLICE-FPGA Locking Manual]]\\
Click here for the [[ffc:locking_electronics:slice-fpga-ii|SLICE-FPGA-II Locking Manual]]\\
Click here for the [[https://www.vescent.com/products/lasers/ffc-100-frequency-comb/|FFC-100 web page]].\\
/*Click here for the [[https://github.com/Vescent/FFC_Firmware_Upgrade-and-FPGA-Software-Firmware|Github page for FFC-100 firmware revisions]]\\ */
/*Click here for the [[https://www.vescent.com/manuals/doku.php?id=ffc:100m|FFC-100 Manual]]\\ */
Please check back for added functionality.  Contact [[sales@vescent.com|sales [at] vescent [dot] com]] for questions and corrections, or to request added functionality.

===== Notice =====
| {{ :warning-sign.png?100&nolink }}  | Do not block the airflow vents on the side of the chassis or the fan inputs & outputs on either the FFC-100 or the SLICE-FPGA. |
|:::| The mode-lock indicator on the GUI front panel cannot detect CW breakthrough. Keep the oscillator current within the range specified in your product's final test documentation or CoC.  |
=====Operating the FFC=====
This document provides instructions on how to operate the Vescent Photonics FFC-100 when controlled by the Vescent SLICE-FPGA or SLICE-FPGA-II.
=====Purchase Includes=====
  * FFC-100 rack-mountable Fiber Frequency Comb
  * Power cord for your country (if known)
  * Certificate of Conformance

===== Absolute Maximum Ratings and Power Input =====
Note: Reported specs are under laboratory conditions. Performance degradation can occur in deployed operation depending on the environment

<WRAP center round box 60%><tabcaption abs_max_rat |Absolute Maximum Ratings>
| **Parameter** | **Rating** |
| Environmental Temperature | 15°C<T<30°C|
| Environmental Humidity | <60% | 
| Environmental Dew Points | <15°C |
| Maximum AC Line Input Current | 2 A |
</tabcaption></WRAP>

The FFC-100 employs a proprietary design hybrid power supply that is both low noise and capable of accepting a range of AC input line voltages.  It will accept input line voltages within the ranges shown in <tabref v_rng>.
<WRAP center round box 60%><tabcaption v_rng |Input Voltage Specifications>
| **Parameter**                                                       | **Value**       | **Units**  |
| Input Line Voltage                                                  | 100-240         | VAC        |
| Frequency                                                           | 50-60           | Hz         |
| Phase                                                               | 1 phase                     ||
| User-serviceable fuse((Located in power receptacle on rear panel))  | T 2.0 A L 250V              ||
</tabcaption></WRAP>

===== Proper Usage =====
| {{ :warning-sign.png?100&nolink }}  | If this instrument is used in a manner not specified by the manufacturer in this manual or other relevant literature, protection provided by the instrument may be impaired. |
|:::| Successful implementation of the FFC-100 depends critically on the design of the whole system: FFC-100, phase locking electronics, and any references to which the FFC is locked or //vice versa//. |


=====Initial Set-up=====
  - Ensure all cables and fibers are connected according to the connection diagram <imgref conn>.((Single frequency reference laser: for instance a [[https://rio-lasers.com/1550nm-laser-diode/|RIO Planex]]<sup>TM</sup> 1550 nm laser.))
  - Ensure the RF input amplitudes to the FPGA are between -30 dBm and -15 dBm. If power levels are higher than -15 dBm, utilize an appropriate RF attenuator.
  - Turn on the power to the Fiber Frequency Comb (FFC) and the FPGA, as well as the reference laser.
  - Ensure the optical input power to the ƒOPT input port is < 1.5 mW.

<imgcaption conn|FFC-100 electrical and optical connection diagram (Click for larger image)>{{ :ffc:updated_ffc_connection_diagram.png?direct&600 |}}</imgcaption>\\
  

<WRAP center round box 60%><tabcaption set_up |Operating Parameters>
| **Parameter** | **Rating** |
|ƒ<sub>opt</sub> Power Input  | <1.5 mW max |
</tabcaption></WRAP>

=====FFC-100 Operation=====
====FFC Start Up GUI====
  - Touch the “System Off” button at the top of the front panel screen (<imgref gui_off>) to bring up a drop-down menu. Select “Standby” (<imgref system_state>) to turn on temperature control of the pump diodes and oscillator cavity. Temperatures will appear yellow as they approach stability, and turn green when stabilized within a predefined temperature range around the setpoint.\\ <imgcaption gui_off|The FFC-100 GUI in off state>{{updated_off_state.png?400 |ffc_gui_off.png}}</imgcaption><imgcaption system_state|Select Standby laser state>{{ updated_standby.png?400 | ffc_gui_choose_state.png}}</imgcaption>\\
  - Once the temperature servos have stabilized and “Standby” has stopped blinking, touch the “Standby” drop-down menu (<imgref stdby>) and select “Laser On” (<imgref stdby_to_on>).  After a 5 second safety delay where the Laser On button blinks, the FFC should commence lasing and the Laser On button should turn solid white (<imgref sys_on>). \\ <imgcaption stdby|The FFC-100 GUI: in Standby mode>{{ffc:updated_standby_on.png?400 | ffc:updated_standby_on.png}}</imgcaption> <imgcaption stdby_to_on|The FFC-100 GUI: Standby to System On>{{ ffc:updated_laser.png?400 | ffc:updated_laser.png }} \\ </imgcaption><imgcaption sys_on|System On>{{ ffc:updated_laser_on.png?400 | ffc:ffc_gui_on.png }}</imgcaption> \\
  - Touch the “PZT” touch screen button (<imgref pzt>) to bring up a drop-down menu and select “Full Range x10” to enable the PZT servo.\\ <imgcaption pzt|Select PZT Gain>{{ :ffc:updated_pzt_menu.png?direct&400 |}}</imgcaption>
====FPGA Control====

| {{ :take-note.png?50&nolink }}  | Visit these pages for the appropriate offset phase lock servo manual \\ [[ffc:locking_electronics:slice-fpga|SLICE-FPGA manual]] \\ [[ffc:locking_electronics:slice-fpga-ii|SLICE-FPGA-II manual]]  |\\

The two channels of the SLICE-FPGA or SLICE-FPGA-II Offset Phase Lock Servo can be used to control a self-referenced phase lock of ƒ<sub>CEO</sub> and a lock of ƒ<sub>opt</sub> to a reference laser such as [[https://stabilaser.dk/stabilized-laser/|the Sabilaser 1542]] or [[https://rio-lasers.com/1550nm-laser-diode/|the RIO Planex]].
{{ :ffc:updated_ss_home_menu_off.svg |}}====Slow Loop Feedback====
Slow servo functionality is designed to allow indefinite FOPT locking times despite long-term drifts in the reference laser’s frequency outside the dynamic range of the FFC’s PZT feedback. This is achieved by slow temperature feedback to the oscillator of the FFC, which locks the PZT output voltage to a setpoint voltage near the middle of its dynamic range. To enable the slow servo, first lock FOPT normally, with the DAC 1 slider as close to centered as possible. Next, navigate to the home screen of the FFC-100 and press the “Slow Servo” button at the top of the screen (<imgref ss_home> and <imgref ss_enabled> ).

<imgcaption ss_home|The slow servo button is located on the home screen to the right of the System Off/Laser On button.>{{ :ffc:updated_ss_home_menu_off.png?400 |}}</imgcaption>

This will activate the slow servo but does not turn on the feedback. You can tell that the slow servo has been activated by the blue background on the “Setpoint [°C]” button. 

<imgcaption ss_enabled | When the slow servo is activated, the slow servo button will turn green, and the temperature “Target [°C]” and “Actual [°C]” buttons will turn yellow or green according to the current state.>{{ :ffc:updated2_ss_enabled.png?400 |}}</imgcaption>

This will activate the slow servo. On the FPGA software under the “Optical Lock” tab, the “DAC 1” slider should be gradually pushed and eventually stabilize in the center of its dynamic range. The gain of the slow servo comes preconfigured for each unit but can be adjusted via a menu accessed by pressing and holding the “Slow Servo” button on the FFC GUI (<imgref ss_menu>) **(We do not advise changing the gain without input from the Vescent technical staff)**.

<imgcaption ss_menu | The slow servo menu allows the user to change the setpoint, gain, and polarity of the servo, and also to turn it on or off.>{{ :ffc:updated2_ss_menu.png?400 |}}</imgcaption>

While the slow servo is on, the color of the “Setpoint [°C]” button will change as the slow servo adjusts the temperature setpoint. A yellow color indicates that the PZT voltage is > 6V away from the setpoint (30V) and the temperature setpoint is being changed to compensate. This box will turn green when the PZT voltage is within the range of ±6V of the voltage setpoint. The color of the “Actual [°C]” box may also momentarily turn yellow as the temperature control servo corrects the cavity temperature when the temperature setpoint changes.

Remember to shut off the slow servo by pressing the On/Off button in the slow servo menu, when unlocking the FFC-100.