J. Kissel"
As is all over the aLOG this morning, LHO had back-to-back site-wide power-outages this past Saturday 2025-05-30 -- LHO:90395. Here's the quick, pain-free record of recovering the SPI pathfinder's function to the levels we left it on Friday 2026-05-29 (LHO:90382). 

LASER
State of laser as I found it (entering the lab with laser safety googles ON):
    - Yellow chain and signage across the entry warning of "laser running unattended" still blocking entry. 
    - Magnetic lock of "outer" curtain released, manually hook-locked "inner" curtain still closed.
    - Laser hazard sign OFF
    - Laser STOP Button still "OUT" (in the ON position)
    - Laser Hazard sign still keyed "ON"
    - NPRO shuttered, still keyed ON, but not powered.

In short -- everything worked as expected in the event of a power outage if it happened while a laser system was running unattended.

    RECOVERY (all with laser safety glasses ON; obviously but just saying it "out loud"):
    - Unchained and stored "unattended laser" sign.
    - Pushed in ("OFF") laser stop button.
    - Keyed OFF laser hazard sign.
    - Pulled out ("ON") laser stop button to allow for re-energizing of interlock.
    - Keyed ON laser hazard sign.
    - Closed magnetic "outer" curtain and swiped in, laser hazard sign lit up as expected.
    - Confirmed NPRO laser output is shuttered. 
    - Looked at NPRO controller, red light ON under the OFF button (as expected because it was already/still keyed ON).
    - Plugged in and turned on PD100D interface for on-board S304C power monitor PD (installed within the laser conditioning/fiber collimating bread-board), confirming 1064 [nm] wavelength readout settings.
    - Waited ~2 minutes for the diodes' controllers to settle, then hit the green ON button
    - No issues with diode temp transients, laser worked just fine.
    - Unshuttered laser, and on-board S304C power monitor PD happily confirmed the expect ~198 [mW].

ELECTRONICS
State of electronics as I found it: 
    - Electronics +/-18 V and +/-24.0 V power supplies were ON, with their outputs producing voltage at their nominal settings.
    - Laser prep chassis and PD TIA chassis all showed happy green lights.
    - Keysight 33600A RF source had reset, with outputs off and all the wrong settings.

    RECOVERY (all with laser safety glasses ON; obviously but just saying it "out loud"):
    - Ran through T2600039 to restore all frequency settings
    - Exported March 2026 notes to LHO:90409 and restored CH1 (REF) and CH2 (MEAS) amplitude settings to -1.7 and -1.4 [dBm], respectively
    - Turned CH1 and CH2 output ON.
    
    Laser Prep Chassis SM05PD01A monitor PD ADC voltage: 7.83 [V].
    Laser Prep Chassis RF monitors M2 (REF) and M3 (MEAS) ADC voltage: ~750 and ~750 [mV]
    FBR_PWRIN_REF On-board power monitor PD ADC voltage: 4.68 [V].
    In short :: All these monitor ADC voltages are at normal values.

SPI IFOs
    No actions required after turning on LASER and ELECTRONICS.
    REF IFO Efficiency -- 4.96 V / (2 * 2.69V) = 0.922
    MEAS IFO Efficiency -- 3.00 V / (2*3.95 V) = 0.38

Recovered! 
Hopping back into The Mystery Machine...