====== Photodiode Étienne ======
These photodiodes were developed by Étienne in cooperation with the AEI and altered to peak at about 16.2MHz.// //

===== Schematics Used =====
  * {{ :groups:mg:private:resonatoren:photodiodeetienne:schematic.pdf |Schematic}}
  * {{ :groups:mg:private:resonatoren:photodiodeetienne:interactive_schematic.zip |Interactive Schematic}}
  * {{ :groups:mg:private:resonatoren:photodiodeetienne:s5971_etc_kpin1025e.pdf |HAMAMATSU S5971: Photodiode @ 960NM, 100MHz}}

===== Notable Changes Made =====
To achieve a peak at around 16.2MHz, components had to be changed.\\
Changed components:
|      ^ Schematic Component                     ^ Used Component  ^
^ L1   | 6u8                                     | 6u8             |
^ C3   | 6p                                      | 2 x 4.7p        |
^ R2   | 40.2R                                   | 40.2R           |
|      ^ Changed only for the 3rd and 4th build                   ||
^ U5   | AD587                                   | LT1236A-10      |
^ C19  | 1u                                      | none            |

  * For Coil L1 the part [[https://www.coilcraft.com/pdfs/1812cs.pdf|1812CS-682XJLC]] (or at least a part with the same form factor) has to be used
  * C3 influences at which frequency the peak will be
  * Instead of the AD587, LT1236A-10 can be used
    * When doing this, the C19 component must not be soldered.
    * C19 connects pin 8 of U5 to ground. Pin 8 is not in use in LT1236A-10.


===== Using The Photodiode =====
  * The photodiode requires a power input of +/- 15V
  * AC Output: right SMA connector
  * DC Output: left SMA connector
  * When using a spectrum-analyzer (e.g. RIGOL DSA815) in combination with the ROHDE&SCHWARZ signal-generator, a 50Ω terminator must be used, too



{{:groups:mg:private:resonatoren:photodiodeetienne:pd_front.jpeg?direct&400|}}
{{:groups:mg:private:resonatoren:photodiodeetienne:pd_rear.jpeg?direct&400|}}

===== Measured Data =====
The {{ :groups:mg:private:resonatoren:photodiodeetienne:messwerte.zip |traces}} of the amplitude and phase were measured.
  * A <color #ff0000>RIGOL Network Analyzer</color> was used to gather that {{ :groups:mg:private:resonatoren:photodiodeetienne:messwerte.zip |data}} from the AC output
  * A 9V test-laser with a modulation of -10dB @ 100MHz was used in this experimental setup
  * The traces of the diodes were fitted in {{ :groups:mg:private:resonatoren:photodiodeetienne:gaussian_fit.py |Python}}

==== The results: ====
^ Diode^ Resonance frequency [MHz]  ^ Peak to 15MHz Ratio [dB]  ^ P14R [dB] ^ P17R [dB] ^ P18R [dB] ^ FWHM with Gauß-Fit [kHz]     ^ Phase #1     ^ Comment  ^
|  1   | 16.11 [+/- 0.015]          | 8.65                      | 13.71     | 6.99      | 12.44     | 271.75                       |              |          |
|  2   | 16.14 [+/- 0.01]           | 8.92                      | 13.46     | 6.53      | 11.34     | 270.98                       |              |          |
|  3   | 16.13 [+/- 0.01]           | 9.17                      | 14.75     | 6.66      | 12.13     | 271.45                       |              |          |
|  4   | 16.16 [+/- 0.01]           | 9.39                      | 14.81     | 6.5       | 12.09     | 269.72                       |              |          |

#1 
<color #ff00ff>Was bedeutet P17 etc?</color>
#2 <color #00ff00>Peak to 17MHz Ratio [Name sollte besser noch geändert werden]</color>
  * X = MAx dazu Y Wert = Peak hight over ..
  * <color #ff0000>Es feht der Fehler von der Linienbreite und des Max Peaks</color>
  * Höhe des Resonanz-Peaks über Rauschen

{{:groups:mg:private:resonatoren:photodiodeetienne:fit1.png |FWHM [Diode 1]: 271750.86662876786Hz}}\\
{{:groups:mg:private:resonatoren:photodiodeetienne:fit2.png|FWHM [Diode 2]: 270984.2391765082Hz}}\\
{{:groups:mg:private:resonatoren:photodiodeetienne:fit3.png |FWHM [Diode 3]: 271450.8282159102Hz}}\\
{{:groups:mg:private:resonatoren:photodiodeetienne:fit4.png|FWHM [Diode 4]: 269724.22527546244Hz}}\\


===== Wechselwirkung (WW) EOM und PD Nr.4 =====

Spektrometer Rhode&Schwarz
RBW: 100Hz
VBW: 10Hz
SWT: 30s 
Ref: 0dBm
Att: 10dB

{{:groups:mg:private:resonatoren:photodiodeetienne:ww_pd_eom_wdh.messung_3.png?400|}}