(kicad_sch (version 20231120) (generator eeschema)
  (paper "A4")
  (title_block
    (title "Wien-Brücken-Oszillator 801 kHz")
    (company "DM8ANE")
    (comment 1 "Optimiert für TL072 Slew-Rate (max 5Vss)")
  )
  (lib_symbols
    (symbol "Simulation_SPICE:OPAMP" (pin_names (offset 0.127)) (in_bom yes) (on_board yes)
      (property "Reference" "X" (at 0 5.08 0))
      (property "Value" "TL072" (at 0 -5.08 0))
      (property "Footprint" "" (at 0 0 0))
      (property "Datasheet" "" (at 0 0 0))
      (property "Sim.Pins" "1=+ 2=- 3=V+ 4=V- 5=out" (at 0 0 0))
      (symbol "OPAMP_0_1"
        (polyline (pts (xy -5.08 5.08) (xy -5.08 -5.08) (xy 5.08 0) (xy -5.08 5.08)))
        (pin input inverted line (at -7.62 -2.54 0) (length 2.54)
          (name "-") (number "2"))
        (pin input non_inverted line (at -7.62 2.54 0) (length 2.54)
          (name "+") (number "1"))
        (pin power_in pos line (at 0 5.08 270) (length 2.54)
          (name "V+") (number "3"))
        (pin power_in neg line (at 0 -5.08 90) (length 2.54)
          (name "V-") (number "4"))
        (pin output output line (at 7.62 0 180) (length 2.54)
          (name "") (number "5"))
      )
    )
    (symbol "Device:R" (pin_numbers hide) (pin_names (offset 0)) (in_bom yes) (on_board yes)
      (property "Reference" "R" (at 2.032 0 90))
      (property "Value" "R" (at -2.032 0 90))
      (symbol "R_0_1"
        (rectangle (start -1.016 -2.54) (end 1.016 2.54))
        (pin passive line (at 0 3.81 270) (length 1.27) (name "~") (number "1"))
        (pin passive line (at 0 -3.81 90) (length 1.27) (name "~") (number "2"))
      )
    )
    (symbol "Device:C" (pin_numbers hide) (pin_names (offset 0)) (in_bom yes) (on_board yes)
      (property "Reference" "C" (at 2.032 0 90))
      (property "Value" "C" (at -2.032 0 90))
      (symbol "C_0_1"
        (polyline (pts (xy -2.032 0.635) (xy 2.032 0.635)))
        (polyline (pts (xy -2.032 -0.635) (xy 2.032 -0.635)))
        (pin passive line (at 0 3.81 270) (length 3.175) (name "~") (number "1"))
        (pin passive line (at 0 -3.81 90) (length 3.175) (name "~") (number "2"))
      )
    )
    (symbol "Device:D" (pin_numbers hide) (pin_names (offset 0)) (in_bom yes) (on_board yes)
      (property "Reference" "D" (at -2.032 0 90))
      (property "Value" "D" (at 2.032 0 90))
      (symbol "D_0_1"
        (polyline (pts (xy -1.27 1.27) (xy -1.27 -1.27)))
        (polyline (pts (xy -1.27 0) (xy 1.27 1.27) (xy 1.27 -1.27) (xy -1.27 0)))
        (pin passive line (at -2.54 0 0) (length 1.27) (name "K") (number "1"))
        (pin passive line (at 2.54 0 180) (length 1.27) (name "A") (number "2"))
      )
    )
    (symbol "power:GND" (power) (pin_names (offset 0)) (in_bom no) (on_board yes)
      (property "Reference" "#PWR" (at 0 -2.54 0))
      (property "Value" "GND" (at 0 -1.905 0))
      (symbol "GND_0_1"
        (polyline (pts (xy 0 0) (xy 0 -1.27)))
        (polyline (pts (xy -1.905 -1.27) (xy 1.905 -1.27)))
        (polyline (pts (xy -1.27 -1.905) (xy 1.27 -1.905)))
        (polyline (pts (xy -0.635 -2.54) (xy 0.635 -2.54)))
        (pin power_in line (at 0 0 270) (length 0) (name "GND") (number "1"))
      )
    )
  )
  ;; SPICE Simulationsparameter als Text auf dem Schaltplan platziert
  (text "--- SPICE CONTROL ---\n.tran 50ns 150us 0us 50ns\n.ic V(n_pos)=0.1\n.model 1N4148 D(Is=2.52n Rs=0.568 N=1.752 Cjo=4p M=0.333 Vj=0.5)\n" 
    (at 20 25 0))
  ;; --- Bauteile Platzierung (Koordinaten in mm) ---
  ;; OPV1 (Oszillator)
  (symbol (lib_id "Simulation_SPICE:OPAMP") (at 100 60 0) (unit 1)
    (property "Reference" "X1" (at 100 52 0))
    (property "Value" "TL072" (at 100 68 0))
  )
  ;; Wien-Brücke (Frequenzbestimmung)
  (symbol (lib_id "Device:C") (at 70 45 90) (unit 1)
    (property "Reference" "C1" (at 70 40 0))
    (property "Value" "1nF" (at 70 50 0))
  )
  (symbol (lib_id "Device:R") (at 85 45 90) (unit 1)
    (property "Reference" "R1" (at 85 40 0))
    (property "Value" "198.7" (at 85 50 0))
  )
  (symbol (lib_id "Device:C") (at 85 75 0) (unit 1)
    (property "Reference" "C2" (at 90 75 0))
    (property "Value" "1nF" (at 90 78 0))
  )
  (symbol (lib_id "Device:R") (at 75 75 0) (unit 1)
    (property "Reference" "R2" (at 70 75 0))
    (property "Value" "198.7" (at 70 78 0))
  )
  ;; Gegenkopplung / Amplitudenstabilisierung
  (symbol (lib_id "Device:R") (at 100 40 90) (unit 1)
    (property "Reference" "R_ff" (at 100 35 0))
    (property "Value" "2k" (at 100 45 0))
  )
  (symbol (lib_id "Device:R") (at 90 40 0) (unit 1)
    (property "Reference" "R_fb" (at 85 40 0))
    (property "Value" "1k" (at 85 43 0))
  )
  (symbol (lib_id "Device:D") (at 90 15 270) (unit 1)
    (property "Reference" "D1" (at 95 15 0))
    (property "Value" "1N4148" (at 95 18 0))
  )
  (symbol (lib_id "Device:D") (at 90 5 90) (unit 1)
    (property "Reference" "D2" (at 85 5 0))
    (property "Value" "1N4148" (at 85 2 0))
  )
  ;; Massepunkte (GND)
  (symbol (lib_id "power:GND") (at 75 82 0) (unit 1))
  (symbol (lib_id "power:GND") (at 85 82 0) (unit 1))
  (symbol (lib_id "power:GND") (at 90 0 0) (unit 1))
  ;; --- Verdrahtung (Wires) ---
  ;; Verbindung Ausgang X1 zu C1/R_ff
  (polyline (pts (xy 107.62 60) (xy 115 60) (xy 115 45) (xy 103.81 45)))
  (polyline (pts (xy 115 45) (xy 115 40) (xy 103.81 40)))
  ;; Wien-Brücke Pfad oben
  (polyline (pts (xy 66.19 45) (xy 60 45) (xy 60 62.54) (xy 92.38 62.54))) ; zu Pin + von X1
  (polyline (pts (xy 73.81 45) (xy 81.19 45)))
  (polyline (pts (xy 88.81 45) (xy 92.38 62.54)))
  ;; Parallelglieder der Wien-Brücke zu GND
  (polyline (pts (xy 92.38 62.54) (xy 92.38 71.19)))
  (polyline (pts (xy 92.38 71.19) (xy 85 71.19)))
  (polyline (pts (xy 92.38 71.19) (xy 75 71.19)))
  (polyline (pts (xy 85 71.19) (xy 85 71.19)))
  (polyline (pts (xy 75 71.19) (xy 75 71.19)))
  ;; Invertierender Knoten (Minus-Eingang)
  (polyline (pts (xy 92.38 57.46) (xy 90 57.46) (xy 90 43.81)))
  (polyline (pts (xy 96.19 40) (xy 90 40)))
  (polyline (pts (xy 90 36.19) (xy 90 20)))
  ;; Diodennetzwerk
  (polyline (pts (xy 90 20) (xy 90 17.54)))
  (polyline (pts (xy 90 12.46) (xy 90 7.54)))
  (polyline (pts (xy 90 2.46) (xy 90 0)))
  ;; Net-Labels für Oszilloskop-Abgriff
  (label "n_out" (at 115 52 90))
  (label "n_pos" (at 62 45 0))
)
