SRS Labs Lock-In Amplifier, SR530 manual Phase Controls

Phase Controls	Adjust phase in smoothly accelerating 0.025° steps, or by
	90° steps. Press both 90° buttons to zero the phase.
Reference LCD	Display reference phase setting or reference frequency
Time Constants	Pre-filter has time constants from 1 mS to 100 S (6 dB/Octave)
	Post-filter has time constants of 0, 0.1 or 1.0 S (6 dB/Octave)
ENBW	Equivalent Noise Bandwidth. Specifies the bandwidth when making
	Noise measurements. (1Hz or 10 Hz ENBW)
Power Switch	Instrument settings from the last use are recalled on power-up

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