EPR spectroscopy endstation

EPR spectroscopy endstation is a multi-functional setup located at the Novosibirsk Free Electron Laser Facility. The endstation consists of 3 EPR machines, namely (i) a pulsed X-band EPR; (ii) a continuous wave X-band EPR; (iii) a time-resolved X-band EPR equipped with a Lotis TII Nd:YAG laser. To be continued...

Hardware

Pulsed machine

Component	Model
Pulse generator / ADC / DAC	Insys FM214x3GDA (312.5 MHz TTL, 2.5 GHz ADC, 1.5 GHz DAC)
Magnetic field controller	BH15
Microwave bridge	Micran X-band v2
Temperature controller	Lakeshore 335

CW EPR machine

Component	Model
Lock-in amplifier	Stanford Research SR-850
Frequency counter	Agilent 53131A
Temperature controller	Lakeshore 335
Magnetic field controller	BH15

TR EPR machine

Component	Model
Oscilloscope (primary)	Keysight DSOX3034A
Oscilloscope (secondary)	Keysight DSOX2012A
Frequency counter	Agilent 53131A
Temperature controller	Lakeshore 335
Magnetic field controller	BH15

Other instruments

Component	Model
NMR gaussmeter	Sibir 1

Per-tool working directories

The endstation runs as several independent Qt processes — the main window plus each control-center tool in its own QProcess. Every open/save dialog uses the last-opened-directory helper so it reopens where you left off, remembered independently per tool and across relaunches.

On top of the common script and data categories, the endstation build adds one category per preset tool, so each remembers its own folder independently:

Key	Tool	File type
cw	CW EPR control	*.cw
tr	TR EPR control	*.tr
tune	resonator tune preset	*.tn
phase	RECT phasing	*.phase
phase_awg	AWG phasing	*.phase_awg
phase_cor	phase correction	*.csv

The data category here also covers the TR data-open dialogs in addition to the 1D / 2D ones.

On the endstation build these <key>_lastdir.txt notes are stored under the repo's libs/ runtime directory, next to the other runtime-IPC files (these files are git-ignored), rather than under the per-user config directory used by plain Atomize.