Sudarshan K, Rick S, Darkhan T.

Pcal beam power measurements were taken at EndY.

Measurements inside TX module:
OFS PD outputs 3720 counts, 2.25 V.
TX PD outputs 1592 counts.
Laser power: 2 W.
Servo loop is open.
Heat sink is not installed.

Power measurements before any optics (after the laser shutter) at different voltages:
1.05 W   at 3.0 V
1.35 W      3.5 V
1.60 W      4.0 V
1.86 W      4.5 V
2.07 W      5.0 V

Power measurements, laser power set at 5 V:
OFS PD: 9.06 V    14850 cts.     2.72 mW
TX PD:  4.2  V     6930 cts.    10.1  mW


Power meter is used with OD1.

NE01A-B + NE02A-B attenuators attached to OFS PD.

Power reading inside of TX module between two lenses (combined power of two beams going to ETMY): 1.69 W.


Measurements of two beams at the TX module:
Inner beam: 844 mW
Outer beam: 824 mW


Measurements of two beams at the RX module:
Inner beam: 827 mW
Outer beam: 810 mW
Both beams combined: 1.63 W
RX PD mon (both beams combined) output: 10.3 V


Pictures of Pcal spots on ETMY (f/22, 30 sec):
LHOetm_0250.jpeg - inner beam only on ETMY (outer beam is blocked)
LHOetm_0251.jpeg - outer beam only on ETMY
LHOetm_0252.jpeg - both beams


We left Pcal laser ON, beams on ETMY.