Differences

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--- d2:laser_servo [2018/11/14 17:37] – [Right Side Panel] Michael Radunsky
+++ d2:laser_servo [2018/11/14 17:39] – [Front Panel] Michael Radunsky
@@ Line 164: / Line 164: @@
 **Coarse Gain (seven-position switch)**
-The COARSE GAIN sets the overall proportional gain of the circuit without changing the location of any zeros or poles in the loop filter transfer function.  Relative to the DC ERROR MONITOR, the Coarse Gain adjusts the gain from 0dB to -60dB.
+The COARSE GAIN sets the overall proportional gain of the circuit without changing the location of any corners or poles in the loop filter transfer function.  Relative to the DC ERROR MONITOR, the Coarse Gain adjusts the gain from 0dB to -60dB.
 The overall loop gain (controlled by both the COARSE GAIN and the FINE GAIN) should be set around the point that minimizes the RMS noise on the DC ERROR MONITOR. This can sometimes result in setting the gain too high because the DC ERROR MONITOR filters high frequencies and thus hides some of the gain peaking with high gain. To precisely set the gain, look at the noise with a spectrum analyzer through the AC ERROR MONITOR.
@@ Line 204: / Line 204: @@
 {{ :d2:d2-125:d2-125_side_panel.jpg?direct&400 |}}</imgcaption></WRAP>
-The feedback loop is defined by the Gain vs Frequency plot shown above. ƒ<sub>I</sub>, ƒ<sub>PI</sub> and ƒ<sub>D</sub> define three zeros in the transfer function. ƒ<sub>I</sub> and ƒ<sub>PI</sub> are the frequencies where the first and second integrators respectively switch from having integral gain to having proportional gain. ƒ<sub>D</sub> is the frequency where the gain switches from proportional to differential. ƒ<sub>I</sub>, ƒ<sub>PI</sub> and ƒ<sub>D</sub> are controlled by two rotary switches, where the upper switch is used to select higher frequencies, and the lower switch is used for selecting the lower frequencies. The upper switch must be in the "low freq" position to engage the lower switch.
+The feedback loop is defined by the Gain vs Frequency plot shown above. ƒ<sub>I</sub>, ƒ<sub>PI</sub> and ƒ<sub>D</sub> define three corners in the transfer function. ƒ<sub>I</sub> and ƒ<sub>PI</sub> are the frequencies where the first and second integrators respectively switch from having integral gain to having proportional gain. ƒ<sub>D</sub> is the frequency where the gain switches from proportional to differential. ƒ<sub>I</sub>, ƒ<sub>PI</sub> and ƒ<sub>D</sub> are controlled by two rotary switches, where the upper switch is used to select higher frequencies, and the lower switch is used for selecting the lower frequencies. The upper switch must be in the "low freq" position to engage the lower switch.
-//NOTE: Adjusting the loop filter poles and zeros while locked may result in loss of lock. If this happens, unlock laser before adjusting poles and zeros and relock laser after adjustment. //
+//NOTE: Adjusting the loop filter corners while locked may result in loss of lock. If this happens, unlock laser before adjusting poles and corners and relock laser after adjustment. //
 //NOTE: The triangle embedded in the rounded side of each click switch points to the selected value. //