diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..2156861
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,42 @@
+
+# Created by https://www.toptal.com/developers/gitignore/api/kicad
+# Edit at https://www.toptal.com/developers/gitignore?templates=kicad
+
+### KiCad ###
+# For PCBs designed using KiCad: http://www.kicad-pcb.org/
+# Format documentation: http://kicad-pcb.org/help/file-formats/
+
+# Temporary files
+*.000
+*.bak
+*.bck
+*.kicad_pcb-bak
+*.sch-bak
+*~
+_autosave-*
+*.tmp
+*-save.pro
+*-save.kicad_pcb
+fp-info-cache
+
+# Netlist files (exported from Eeschema)
+*.net
+
+# Autorouter files (exported from Pcbnew)
+*.dsn
+*.ses
+
+# Exported BOM files
+*.xml
+*.csv
+
+### KiCad Patch ###
+rescue-backup/
+
+*.tsv
+bom/
+
+# Gerber export output
+out/
+
+# End of https://www.toptal.com/developers/gitignore/api/kicad
diff --git a/README.md b/README.md
index 7645493..c461137 100644
--- a/README.md
+++ b/README.md
@@ -5,6 +5,7 @@ But the required hardware for simultaneous translation is quite expensive to ren
 So the idea was born to design an easy to use hardware with the special requirements of our interpreters in mind.
 
 
+
 ## Requirements
 The hardware unit should deliver the native audio (stage/ hall mix) to the interpreter's headset and provide a sum of all interpreter's microphone to the input of the video streaming/ recording chain.
 Mixing of the final translated audio (ducking the native audio with the translation) will be done as part of the streaming/ recording chain, so the interpreter unit should just provide the sum of all microphones.
@@ -20,7 +21,7 @@ General requirements:
 - 3x Microphone input (XLR) (at first just dynamic microphones)
     * VU-Meter for each input channel. (Perhaps with special color scheme: too quiet, good, too loud, clipping)
     * Fader/ Potentiometer for gain control
-    * Mute switch (on/ off position, with state LED)
+    * On-Air switch (on/ off position, with state LED)
     * Temporary mute button (momentary switch)
 - 3x Headphone output (6.3 mm mono/ stereo (2x mono) jack)
     * Should output mix of native audio and own microphone
@@ -34,7 +35,112 @@ All inputs (besides the microphones) and outputs should:
 - be transformer balanced and galvanically isolated
 
 
+
 ## Status
-Requirements collection done, first research for circuit design, but no real progress yet.
+
+### Tasks
+- [x] Requirements collection
+- [ ] Electrical design draft/ proof of concept (breadboard)
+- [ ] Proof of concept validation
+- [ ] First PCB layout
+- [ ] More testing/ validation
 
 Help is always appreciated!
+
+### Implemented Requirements
+- [x] Microphone input
+- [x] Line input
+- [x] Microphone summing and line output driver
+- [x] Adjustable headphone mix and output volume
+- [ ] ESD protection and galvanic isolation of line inputs and outputs
+- [ ] VU meter
+- [ ] Mute and On-Air buttons
+
+
+## Electrical Design
+This chapter contains some notes on the electrical design.
+Currently just the sources of the used circuit designs.
+
+
+### Sources and Design Considerations
+
+#### Microphone Input
+##### Preamplifier
+For the microphone preamp, we are using the NE5534 low-noise opamp with a circuit design from [circuitlib microphone pre-amp](https://www.circuitlib.com/index.php/schematics/product/29-balanced-microphone-preamplifier).
+
+##### Controllable Amplification
+In a normal mixer, you would be able to lower the microphone's volume to zero.
+But in our case we just need on/ off and some gain range to adjust for different microphones and loudness of different people.
+
+TODO: Try, if the preamp's gain of about 50 dB is enough and how much gain is need in this stage.
+From theoretical calculations, we might need another 30 to 40 dB here, which needs to be adjustable in a range of about 30 dB.
+
+TODO: Try out using the amp's feedback resistor for gain control or just use a potentiometer on the input of the next stage.
+
+TODO: Integrate the On-Air and mute buttons
+
+For long-lasting endurance of the microphone level potentiometer, we're using one with conductive plastic as resistor element (Bourns model 91).
+
+#### Line Input/ Input Module
+The line input must not be amplified at all, because loudness control of the headphones is done by the headphone amplifier section.
+But the differential line-level signal must be converted to a single-ended signal by the input stage.
+
+The current design uses a LM833N opamp to convert the balanced signal into a single ended signal and has a second LM833N to provide some degree (+- 6 dB) of "factory" adjustment.
+The second part of that circuit was taken from the [circuitlib audio mixer tutorial](https://www.circuitlib.com/index.php/tutorials/product/39-how-to-build-an-audio-mixer).
+
+TODO: How to achieve galvanic isolation?
+
+TODO: Use https://www.ti.com/product/INA134 for input conversion?
+
+#### Summing
+Summing is needed in two places: Creating the sum of all microphones (not adjustable, fixed output gain) and for the headphone mix (one input level adjustable).
+A simple summing circuit using one operational amplifier is enough for our application, like in [circuitlib audio mixer tutorial](https://www.circuitlib.com/index.php/tutorials/product/39-how-to-build-an-audio-mixer).
+
+#### Line Output Driver
+TODO: Either use https://www.ti.com/product/DRV134 or http://www.thatcorp.com/1600-series_Balanced_Line_Driver_ICs.shtml.
+
+TODO: How to achieve galvanic isolation?
+
+#### Headphone Output Driver
+The headphone output needs a maximum output power of about 0.1 W and should put the mono signal on both stereo channels of the TRS jack.
+
+For the first draft, we're using one LM386 audio power amplifier.
+
+TODO: Check, if driving the two speakers in parallel leads to any issues (besides cutting the speaker impedance in half).
+
+#### VU Meter
+Because the LM3916 LED bar graph driver is obsolete, we either have to re-create it's function with some comperators or have to use a microcontroller.
+
+TODO: Re-create the LM3916 with some LM339 or design/ program some small uC.
+
+
+
+## Notes
+A dynamic microphone needs at least 60 dB gain in the pre-amp, because a typical signal is at about 1 - 100 uV (-118 to -78 dBu or -120 to -80 dBV).
+
+Line level in professional audio gear is at +4 dBu, which is 1.228 V (RMS).
+Because 0 dBu is defined as 1 mW at a load of 600 Ohm, which needs a voltage of 0.77 V.
+Increasing the voltage by a factor of 10 is an amplification of 20 dB.
+
+
+
+## BoM
+Approximate prices in Euro.
+
+Connectors and Buttons (User Interface)
+
+| Count | Art. No.           | Description      | Price |
+|-------|--------------------|------------------|-------|
+| 1     | Neutrik NCJ 6 FAH  | Line Input       | 1,27  |
+| 1     | Neutrik NC3 FD-LX  | Microphone Input | 3,44  |
+| 1     | Neutrik NJ3 FP-6-C | Headphone Output | 5,40  |
+| 1     | Neutrik NC3 MD-LX  | Line Output      | 3,22  |
+| 1     | Neutrik NAC3 MPA-1 | Main Power Input | 3,33  |
+
+Sub-Components
+
+| Count | Art. No.           | Description      | Price  |
+|-------|--------------------|------------------|--------|
+| 1     | Traco Power TXL 035-1515D or TOP 60533 | Power Supply     | ~48,00 |
+
+PCB Components: TODO when schematic is finished
diff --git a/c3lingo-interpreter-unit-v0.1.pdf b/c3lingo-interpreter-unit-v0.1.pdf
new file mode 100644
index 0000000..98ec417
Binary files /dev/null and b/c3lingo-interpreter-unit-v0.1.pdf differ
diff --git a/schematics/c3lingo-interpreter-unit-cache.lib b/schematics/c3lingo-interpreter-unit-cache.lib
new file mode 100644
index 0000000..722b5a7
--- /dev/null
+++ b/schematics/c3lingo-interpreter-unit-cache.lib
@@ -0,0 +1,458 @@
+EESchema-LIBRARY Version 2.4
+#encoding utf-8
+#
+# Amplifier_Audio_LM386
+#
+DEF Amplifier_Audio_LM386 U 0 5 Y Y 1 F N
+F0 "U" 50 300 50 H V L CNN
+F1 "Amplifier_Audio_LM386" 50 200 50 H V L CNN
+F2 "" 100 100 50 H I C CNN
+F3 "" 200 200 50 H I C CNN
+$FPLIST
+ SOIC*3.9x4.9mm*P1.27mm*
+ DIP*W7.62mm*
+ MSSOP*P0.65mm*
+ TSSOP*3x3mm*P0.5mm*
+$ENDFPLIST
+DRAW
+P 4 0 1 10 200 0 -200 200 -200 -200 200 0 f
+X GAIN 1 0 -300 200 U 50 20 1 1 I
+X - 2 -300 -100 100 R 50 50 1 1 I
+X + 3 -300 100 100 R 50 50 1 1 I
+X GND 4 -100 -300 150 U 50 50 1 1 W
+X ~ 5 300 0 100 L 50 50 1 1 O
+X V+ 6 -100 300 150 D 50 50 1 1 W
+X BYPASS 7 0 300 200 D 50 20 1 1 I
+X GAIN 8 100 -300 250 U 50 20 1 1 I
+ENDDRAW
+ENDDEF
+#
+# Amplifier_Operational_LM358
+#
+DEF Amplifier_Operational_LM358 U 0 5 Y Y 3 L N
+F0 "U" 0 200 50 H V L CNN
+F1 "Amplifier_Operational_LM358" 0 -200 50 H V L CNN
+F2 "" 0 0 50 H I C CNN
+F3 "" 0 0 50 H I C CNN
+ALIAS LM358 AD8620 LMC6062 LMC6082 TL062 TL072 TL082 NE5532 SA5532 RC4558 RC4560 RC4580 LMV358 TS912 TSV912IDT TSV912IST TLC272 TLC277 MCP602 OPA1678 OPA2134 OPA2340 OPA2376xxD OPA2376xxDGK MC33078 MC33178 LM4562 OP249 OP275 ADA4075-2 MCP6002-xP MCP6002-xSN MCP6002-xMS LM7332 OPA2333xxD OPA2333xxDGK LMC6482 LT1492 LTC6081xMS8 LM6172 MCP6L92 NJM2043 NJM2114 NJM4556A NJM4558 NJM4559 NJM4560 NJM4580 NJM5532 ADA4807-2ARM OPA2691 LT6234 OPA2356xxD OPA2356xxDGK OPA1612AxD MC33172 OPA1602 TLV2372 LT6237 OPA2277 MCP6022
+$FPLIST
+ SOIC*3.9x4.9mm*P1.27mm*
+ DIP*W7.62mm*
+ TO*99*
+ OnSemi*Micro8*
+ TSSOP*3x3mm*P0.65mm*
+ TSSOP*4.4x3mm*P0.65mm*
+ MSOP*3x3mm*P0.65mm*
+ SSOP*3.9x4.9mm*P0.635mm*
+ LFCSP*2x2mm*P0.5mm*
+ *SIP*
+ SOIC*5.3x6.2mm*P1.27mm*
+$ENDFPLIST
+DRAW
+P 4 1 1 10 -200 200 200 0 -200 -200 -200 200 f
+P 4 2 1 10 -200 200 200 0 -200 -200 -200 200 f
+X ~ 1 300 0 100 L 50 50 1 1 O
+X - 2 -300 -100 100 R 50 50 1 1 I
+X + 3 -300 100 100 R 50 50 1 1 I
+X + 5 -300 100 100 R 50 50 2 1 I
+X - 6 -300 -100 100 R 50 50 2 1 I
+X ~ 7 300 0 100 L 50 50 2 1 O
+X V- 4 -100 -300 150 U 50 50 3 1 W
+X V+ 8 -100 300 150 D 50 50 3 1 W
+ENDDRAW
+ENDDEF
+#
+# Amplifier_Operational_NE5534
+#
+DEF Amplifier_Operational_NE5534 U 0 5 Y Y 1 F N
+F0 "U" 50 250 50 H V L CNN
+F1 "Amplifier_Operational_NE5534" 50 150 50 H V L CNN
+F2 "" 50 50 50 H I C CNN
+F3 "" 50 150 50 H I C CNN
+ALIAS SA5534 LM101 LM201 LM301 AD797 LT1012
+$FPLIST
+ DIP*W7.62mm*
+ SOIC*3.9x4.9mm*P1.27mm*
+ TO?5*
+$ENDFPLIST
+DRAW
+P 4 0 1 10 -200 200 200 0 -200 -200 -200 200 f
+X BAL 1 0 -300 200 U 50 20 1 1 I
+X - 2 -300 -100 100 R 50 50 1 1 I
+X + 3 -300 100 100 R 50 50 1 1 I
+X V- 4 -100 -300 150 U 50 50 1 1 W
+X COMP 5 100 -300 250 U 50 20 1 1 I
+X ~ 6 300 0 100 L 50 50 1 1 O
+X V+ 7 -100 300 150 D 50 50 1 1 W
+X C/B 8 0 300 200 D 50 20 1 1 I
+ENDDRAW
+ENDDEF
+#
+# Connector_AudioJack3_Ground
+#
+DEF Connector_AudioJack3_Ground J 0 20 Y Y 1 F N
+F0 "J" 0 350 50 H V C CNN
+F1 "Connector_AudioJack3_Ground" 0 250 50 H V C CNN
+F2 "" 0 0 50 H I C CNN
+F3 "" 0 0 50 H I C CNN
+$FPLIST
+ Jack*
+$ENDFPLIST
+DRAW
+S -200 -100 -250 -200 0 1 10 F
+S 100 150 -200 -200 0 1 10 f
+P 4 0 1 10 0 -100 25 -125 50 -100 100 -100 N
+P 5 0 1 10 -75 -100 -50 -125 -25 -100 -25 0 100 0 N
+P 5 0 1 10 100 100 -100 100 -100 -100 -125 -125 -150 -100 N
+X ~ G 0 -300 100 U 50 50 1 1 P
+X ~ R 200 0 100 L 50 50 1 1 P
+X ~ S 200 100 100 L 50 50 1 1 P
+X ~ T 200 -100 100 L 50 50 1 1 P
+ENDDRAW
+ENDDEF
+#
+# Connector_Conn_01x03_Male
+#
+DEF Connector_Conn_01x03_Male J 0 40 Y N 1 F N
+F0 "J" 0 200 50 H V C CNN
+F1 "Connector_Conn_01x03_Male" 0 -200 50 H V C CNN
+F2 "" 0 0 50 H I C CNN
+F3 "" 0 0 50 H I C CNN
+$FPLIST
+ Connector*:*_1x??_*
+$ENDFPLIST
+DRAW
+S 34 -95 0 -105 1 1 6 F
+S 34 5 0 -5 1 1 6 F
+S 34 105 0 95 1 1 6 F
+P 2 1 1 6 50 -100 34 -100 N
+P 2 1 1 6 50 0 34 0 N
+P 2 1 1 6 50 100 34 100 N
+X Pin_1 1 200 100 150 L 50 50 1 1 P
+X Pin_2 2 200 0 150 L 50 50 1 1 P
+X Pin_3 3 200 -100 150 L 50 50 1 1 P
+ENDDRAW
+ENDDEF
+#
+# Connector_XLR3_AudioJack3_Combo_Ground
+#
+DEF Connector_XLR3_AudioJack3_Combo_Ground J 0 20 Y N 2 F N
+F0 "J" 0 400 50 H V C CNN
+F1 "Connector_XLR3_AudioJack3_Combo_Ground" 0 300 50 H V C CNN
+F2 "" 0 0 50 H I C CNN
+F3 "" 0 0 50 H I C CNN
+$FPLIST
+ Jack*XLR*6.35mm*
+$ENDFPLIST
+DRAW
+C -140 0 40 1 1 0 N
+C 0 -140 40 1 1 0 N
+C 0 0 200 1 1 0 f
+C 140 0 40 1 1 0 N
+T 0 -140 70 40 0 1 1 1 Normal 1 C C
+T 0 140 70 40 0 1 1 2 Normal 1 C C
+T 0 0 -70 40 0 1 1 3 Normal 1 C C
+S -200 -100 -250 -200 2 1 10 F
+S 100 150 -200 -200 2 1 10 f
+P 2 1 1 0 -200 0 -180 0 N
+P 2 1 1 0 -100 -200 -100 -175 N
+P 2 1 1 0 0 -200 0 -180 N
+P 2 1 1 0 200 0 180 0 N
+P 4 2 1 10 0 -100 25 -125 50 -100 100 -100 N
+P 5 2 1 10 -75 -100 -50 -125 -25 -100 -25 0 100 0 N
+P 5 2 1 10 100 100 -100 100 -100 -100 -125 -125 -150 -100 N
+X ~ 1 -300 0 100 R 50 50 1 1 P
+X ~ 2 300 0 100 L 50 50 1 1 P
+X ~ 3 0 -300 100 U 50 50 1 1 P
+X ~ G -100 -300 100 U 50 50 1 1 P
+X ~ R 200 0 100 L 50 50 2 1 P
+X ~ S 200 100 100 L 50 50 2 1 P
+X ~ T 200 -100 100 L 50 50 2 1 P
+ENDDRAW
+ENDDEF
+#
+# Connector_XLR3_Ground
+#
+DEF Connector_XLR3_Ground J 0 20 Y N 1 F N
+F0 "J" 0 350 50 H V C CNN
+F1 "Connector_XLR3_Ground" 0 250 50 H V C CNN
+F2 "" 0 0 50 H I C CNN
+F3 "" 0 0 50 H I C CNN
+$FPLIST
+ Jack*XLR*
+$ENDFPLIST
+DRAW
+C -140 0 40 0 1 0 N
+C 0 -140 40 0 1 0 N
+C 0 0 200 0 1 0 f
+C 140 0 40 0 1 0 N
+T 0 -140 70 40 0 0 1 1 Normal 1 C C
+T 0 140 70 40 0 0 1 2 Normal 1 C C
+T 0 0 -70 40 0 0 1 3 Normal 1 C C
+P 2 0 1 0 -200 0 -180 0 N
+P 2 0 1 0 -100 -200 -100 -175 N
+P 2 0 1 0 0 -200 0 -180 N
+P 2 0 1 0 200 0 180 0 N
+X ~ 1 -300 0 100 R 50 50 0 1 P
+X ~ 2 300 0 100 L 50 50 0 1 P
+X ~ 3 0 -300 100 U 50 50 0 1 P
+X ~ G -100 -300 100 U 50 50 1 1 P
+ENDDRAW
+ENDDEF
+#
+# Converter_ACDC_TMLM04253
+#
+DEF Converter_ACDC_TMLM04253 PS 0 20 Y Y 1 F N
+F0 "PS" 0 250 50 H V C CNN
+F1 "Converter_ACDC_TMLM04253" 0 -250 50 H V C CNN
+F2 "Converter_ACDC:Converter_ACDC_TRACO_TMLM-04_THT" 0 -350 50 H I C CNN
+F3 "" 0 0 50 H I C CNN
+ALIAS TMLM04253
+$FPLIST
+ Converter*ACDC*TRACO*TMLM*04*
+$ENDFPLIST
+DRAW
+A -285 38 28 -1525 -275 0 1 0 N -310 25 -260 25
+A -235 11 29 292 1508 0 1 0 N -210 25 -260 25
+S -400 200 400 -200 0 1 10 f
+P 2 0 1 0 -310 -25 -210 -25 N
+P 2 0 1 0 0 -100 0 -150 N
+P 2 0 1 0 0 0 0 -50 N
+P 2 0 1 0 0 100 0 50 N
+P 2 0 1 0 0 200 0 150 N
+X Vout1 2 500 100 100 L 50 50 1 1 w
+X Common 3 500 0 100 L 50 50 1 1 w
+X Vout2 4 500 -100 100 L 50 50 1 1 w
+X AC(L) 5 -500 100 100 R 50 50 1 1 W
+X AC(N) 6 -500 -100 100 R 50 50 1 1 W
+ENDDRAW
+ENDDEF
+#
+# Device_C
+#
+DEF Device_C C 0 10 N Y 1 F N
+F0 "C" 25 100 50 H V L CNN
+F1 "Device_C" 25 -100 50 H V L CNN
+F2 "" 38 -150 50 H I C CNN
+F3 "" 0 0 50 H I C CNN
+$FPLIST
+ C_*
+$ENDFPLIST
+DRAW
+P 2 0 1 20 -80 -30 80 -30 N
+P 2 0 1 20 -80 30 80 30 N
+X ~ 1 0 150 110 D 50 50 1 1 P
+X ~ 2 0 -150 110 U 50 50 1 1 P
+ENDDRAW
+ENDDEF
+#
+# Device_CP
+#
+DEF Device_CP C 0 10 N Y 1 F N
+F0 "C" 25 100 50 H V L CNN
+F1 "Device_CP" 25 -100 50 H V L CNN
+F2 "" 38 -150 50 H I C CNN
+F3 "" 0 0 50 H I C CNN
+$FPLIST
+ CP_*
+$ENDFPLIST
+DRAW
+S -90 20 90 40 0 1 0 N
+S 90 -20 -90 -40 0 1 0 F
+P 2 0 1 0 -70 90 -30 90 N
+P 2 0 1 0 -50 110 -50 70 N
+X ~ 1 0 150 110 D 50 50 1 1 P
+X ~ 2 0 -150 110 U 50 50 1 1 P
+ENDDRAW
+ENDDEF
+#
+# Device_R
+#
+DEF Device_R R 0 0 N Y 1 F N
+F0 "R" 80 0 50 V V C CNN
+F1 "Device_R" 0 0 50 V V C CNN
+F2 "" -70 0 50 V I C CNN
+F3 "" 0 0 50 H I C CNN
+$FPLIST
+ R_*
+$ENDFPLIST
+DRAW
+S -40 -100 40 100 0 1 10 N
+X ~ 1 0 150 50 D 50 50 1 1 P
+X ~ 2 0 -150 50 U 50 50 1 1 P
+ENDDRAW
+ENDDEF
+#
+# Device_R_POT
+#
+DEF Device_R_POT RV 0 40 Y N 1 F N
+F0 "RV" -175 0 50 V V C CNN
+F1 "Device_R_POT" -100 0 50 V V C CNN
+F2 "" 0 0 50 H I C CNN
+F3 "" 0 0 50 H I C CNN
+$FPLIST
+ Potentiometer*
+$ENDFPLIST
+DRAW
+S 40 100 -40 -100 0 1 10 N
+P 2 0 1 0 100 0 60 0 N
+P 4 0 1 0 45 0 90 20 90 -20 45 0 F
+X 1 1 0 150 50 D 50 50 1 1 P
+X 2 2 150 0 50 L 50 50 1 1 P
+X 3 3 0 -150 50 U 50 50 1 1 P
+ENDDRAW
+ENDDEF
+#
+# JBeyerstedt-Library_DRV134PA
+#
+DEF JBeyerstedt-Library_DRV134PA U 0 10 Y Y 1 F N
+F0 "U" 800 500 60 H V C CNN
+F1 "JBeyerstedt-Library_DRV134PA" 800 400 60 H V C CNN
+F2 "Package_DIP:DIP-8_W7.62mm" 800 340 60 H I C CNN
+F3 "" 0 -300 60 H I C CNN
+$FPLIST
+ P8_TEX
+$ENDFPLIST
+DRAW
+P 2 1 1 5 300 -900 1300 -900 N
+P 2 1 1 5 300 300 300 -900 N
+P 2 1 1 5 1300 -900 1300 300 N
+P 2 1 1 5 1300 300 300 300 N
+X VO- 1 1600 -450 300 L 59 59 1 1 O
+X SENSE- 2 1600 -300 300 L 59 59 1 1 I
+X GND 3 1600 -750 300 L 59 59 1 1 W
+X VIN 4 0 -300 300 R 59 59 1 1 I
+X V- 5 0 -750 300 R 59 59 1 1 W
+X V+ 6 0 150 300 R 59 59 1 1 W
+X SENSE+ 7 1600 0 300 L 59 59 1 1 I
+X VO+ 8 1600 150 300 L 59 59 1 1 O
+ENDDRAW
+ENDDEF
+#
+# JBeyerstedt-Library_INA134PA
+#
+DEF JBeyerstedt-Library_INA134PA U 0 10 Y Y 1 F N
+F0 "U" 800 500 60 H V C CNN
+F1 "JBeyerstedt-Library_INA134PA" 800 400 60 H V C CNN
+F2 "Package_DIP:DIP-8_W7.62mm" 800 340 60 H I C CNN
+F3 "" 0 -200 60 H I C CNN
+$FPLIST
+ P8
+$ENDFPLIST
+DRAW
+S 300 300 1300 -900 0 1 0 N
+X REF 1 0 -750 300 R 59 59 1 1 W
+X IN- 2 0 -200 300 R 59 59 1 1 I
+X IN+ 3 0 -450 300 R 59 59 1 1 I
+X V- 4 1600 -750 300 L 59 59 1 1 W
+X SENSE 5 1600 -200 300 L 59 59 1 1 I
+X OUTPUT 6 1600 -450 300 L 59 59 1 1 O
+X V+ 7 1600 150 300 L 59 59 1 1 W
+X NC 8 0 150 300 R 59 59 1 1 N
+ENDDRAW
+ENDDEF
+#
+# Switch_SW_Push_Open
+#
+DEF Switch_SW_Push_Open SW 0 40 N N 1 F N
+F0 "SW" 0 100 50 H V C CNN
+F1 "Switch_SW_Push_Open" 0 -75 50 H V C CNN
+F2 "" 0 200 50 H I C CNN
+F3 "" 0 200 50 H I C CNN
+DRAW
+C -80 0 20 0 1 0 N
+C 80 0 20 0 1 0 N
+P 2 0 1 0 -100 -25 100 -25 N
+P 2 0 1 0 0 -25 0 50 N
+X A 1 -200 0 100 R 50 50 0 1 P
+X B 2 200 0 100 L 50 50 1 1 P
+ENDDRAW
+ENDDEF
+#
+# Switch_SW_SPST_LED
+#
+DEF Switch_SW_SPST_LED SW 0 40 Y N 1 F N
+F0 "SW" 25 225 50 H V L CNN
+F1 "Switch_SW_SPST_LED" 0 -125 50 H V C CNN
+F2 "" 0 300 50 H I C CNN
+F3 "" 0 300 50 H I C CNN
+DRAW
+C -80 100 20 0 1 0 N
+C 80 100 20 0 1 0 N
+P 2 0 0 0 -150 -75 -100 -25 N
+P 2 0 0 0 -100 -75 -50 -25 N
+P 2 0 0 0 -100 0 100 0 N
+P 2 0 0 0 -25 50 -25 -50 N
+P 3 0 0 0 -150 -50 -150 -75 -125 -75 N
+P 3 0 0 0 -100 -50 -100 -75 -75 -75 N
+P 4 0 0 0 -25 0 50 50 50 -50 -25 0 F
+P 2 0 1 0 -60 110 80 170 N
+X 1 1 -200 100 100 R 50 50 0 1 P
+X 2 2 200 100 100 L 50 50 0 1 P
+X K 3 -200 0 100 R 50 50 0 1 P
+X A 4 200 0 100 L 50 50 0 1 P
+ENDDRAW
+ENDDEF
+#
+# power_+15V
+#
+DEF power_+15V #PWR 0 0 Y Y 1 F P
+F0 "#PWR" 0 -150 50 H I C CNN
+F1 "power_+15V" 0 140 50 H V C CNN
+F2 "" 0 0 50 H I C CNN
+F3 "" 0 0 50 H I C CNN
+DRAW
+P 2 0 1 0 -30 50 0 100 N
+P 2 0 1 0 0 0 0 100 N
+P 2 0 1 0 0 100 30 50 N
+X +15V 1 0 0 0 U 50 50 1 1 W N
+ENDDRAW
+ENDDEF
+#
+# power_-15V
+#
+DEF power_-15V #PWR 0 0 Y Y 1 F P
+F0 "#PWR" 0 100 50 H I C CNN
+F1 "power_-15V" 0 150 50 H V C CNN
+F2 "" 0 0 50 H I C CNN
+F3 "" 0 0 50 H I C CNN
+DRAW
+P 6 0 1 0 0 0 0 50 30 50 0 100 -30 50 0 50 F
+X -15V 1 0 0 0 U 50 50 0 0 W N
+ENDDRAW
+ENDDEF
+#
+# power_Earth_Protective
+#
+DEF power_Earth_Protective #PWR 0 0 Y Y 1 F P
+F0 "#PWR" 250 -250 50 H I C CNN
+F1 "power_Earth_Protective" 450 -150 50 H I C CNN
+F2 "" 0 -100 50 H I C CNN
+F3 "" 0 -100 50 H I C CNN
+DRAW
+C 0 -150 100 0 1 0 N
+P 2 0 1 0 -25 -175 25 -175 N
+P 2 0 1 0 -5 -200 5 -200 N
+P 2 0 1 0 0 -150 0 0 N
+P 2 0 1 0 50 -150 -50 -150 N
+X Earth_Protective 1 0 0 0 D 50 50 1 1 W N
+ENDDRAW
+ENDDEF
+#
+# power_GNDREF
+#
+DEF power_GNDREF #PWR 0 0 Y Y 1 F P
+F0 "#PWR" 0 -250 50 H I C CNN
+F1 "power_GNDREF" 0 -150 50 H V C CNN
+F2 "" 0 0 50 H I C CNN
+F3 "" 0 0 50 H I C CNN
+DRAW
+P 2 0 1 0 -25 -75 25 -75 N
+P 2 0 1 0 -5 -100 5 -100 N
+P 2 0 1 0 0 -50 0 0 N
+P 2 0 1 0 50 -50 -50 -50 N
+X GNDREF 1 0 0 0 D 50 50 1 1 W N
+ENDDRAW
+ENDDEF
+#
+#End Library
diff --git a/schematics/c3lingo-interpreter-unit.kicad_pcb b/schematics/c3lingo-interpreter-unit.kicad_pcb
new file mode 100644
index 0000000..02c8ecb
--- /dev/null
+++ b/schematics/c3lingo-interpreter-unit.kicad_pcb
@@ -0,0 +1 @@
+(kicad_pcb (version 4) (host kicad "dummy file") )
diff --git a/schematics/c3lingo-interpreter-unit.pro b/schematics/c3lingo-interpreter-unit.pro
new file mode 100644
index 0000000..47dc702
--- /dev/null
+++ b/schematics/c3lingo-interpreter-unit.pro
@@ -0,0 +1,14 @@
+update=Monday, 12 October 2020 at 12:14:27
+last_client=kicad
+[general]
+version=1
+[schematic_editor]
+version=1
+PageLayoutDescrFile=
+PlotDirectoryName=
+SubpartIdSeparator=0
+SubpartFirstId=65
+NetFmtName=Pcbnew
+SpiceAjustPassiveValues=0
+LabSize=50
+ERC_TestSimilarLabels=1
diff --git a/schematics/c3lingo-interpreter-unit.sch b/schematics/c3lingo-interpreter-unit.sch
new file mode 100644
index 0000000..ab6446d
--- /dev/null
+++ b/schematics/c3lingo-interpreter-unit.sch
@@ -0,0 +1,2049 @@
+EESchema Schematic File Version 4
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+EELAYER END
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+F 3 "https://www.neutrik.com/de/produkt/nc3fd-lx.pdf" H 900 1900 50  0001 C CNN
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+	1    0    0    -1  
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+F 3 "https://www.neutrik.com/de/produkt/ncj6fa-h.pdf" H 850 8900 50  0001 C CNN
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+F 3 "https://www.neutrik.com/de/produkt/nc3md-lx.pdf" H 15300 4400 50  0001 C CNN
+	1    15300 4400
+	-1   0    0    -1  
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+F 3 "https://www.neutrik.com/de/produkt/nj3fp6c.pdf" H 15200 1800 50  0001 C CNN
+	1    15200 1800
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+F 3 "" H 700 2300 50  0001 C CNN
+	1    700  2300
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+F 2 "" H 3288 3150 50  0001 C CNN
+F 3 "~" H 3250 3300 50  0001 C CNN
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+F 3 "" H 3600 2600 50  0001 C CNN
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+F 2 "" H 2400 3000 50  0001 C CNN
+F 3 "" H 2400 3000 50  0001 C CNN
+	1    2400 3000
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+F 0 "C2" V 2698 1100 50  0000 C CNN
+F 1 "100nF" V 2789 1100 50  0000 C CNN
+F 2 "" H 2988 950 50  0001 C CNN
+F 3 "~" H 2950 1100 50  0001 C CNN
+	1    2950 1100
+	0    1    1    0   
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+L power:GNDREF #PWR04
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+F 1 "GNDREF" H 3705 827 50  0000 C CNN
+F 2 "" H 3700 1000 50  0001 C CNN
+F 3 "" H 3700 1000 50  0001 C CNN
+	1    3700 1000
+	1    0    0    -1  
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+F 1 "10uF" V 4014 2000 50  0000 C CNN
+F 2 "" H 3888 1850 50  0001 C CNN
+F 3 "~" H 3850 2000 50  0001 C CNN
+	1    3850 2000
+	0    -1   -1   0   
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+U 1 1 5F86655E
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+F 0 "R7" H 4030 2204 50  0000 R CNN
+F 1 "5.6K" H 4030 2295 50  0000 R CNN
+F 2 "" V 4030 2250 50  0001 C CNN
+F 3 "~" H 4100 2250 50  0001 C CNN
+	1    4100 2250
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+Wire Wire Line
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+Wire Wire Line
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+Wire Wire Line
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+Wire Wire Line
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+Wire Wire Line
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+Wire Wire Line
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+Wire Wire Line
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+Wire Wire Line
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+U 1 1 5F863B13
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+F 1 "100uF" V 3414 800 50  0000 C CNN
+F 2 "" H 3288 650 50  0001 C CNN
+F 3 "~" H 3250 800 50  0001 C CNN
+	1    3250 800 
+	0    -1   -1   0   
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+Text Notes 1600 3000 0    50   ~ 0
+Mic Preamp\nGain: 50 dB
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+F 2 "" H 1400 9400 50  0001 C CNN
+F 3 "" H 1400 9400 50  0001 C CNN
+	1    1400 9400
+	1    0    0    -1  
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+F 2 "" H 15500 4700 50  0001 C CNN
+F 3 "" H 15500 4700 50  0001 C CNN
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+F 2 "" H 15200 2100 50  0001 C CNN
+F 3 "" H 15200 2100 50  0001 C CNN
+	1    15200 2100
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+Connection ~ 15200 2100
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+F 1 "NE5534" H 3094 1955 50  0000 L CNN
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+F 3 "" H 2800 2150 50  0001 C CNN
+	1    2750 2000
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+F 2 "Package_DIP:DIP-8_W7.62mm" H 3100 9000 50  0001 C CNN
+F 3 "" H 3100 9000 50  0001 C CNN
+	1    3100 9000
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+F 3 "" H 5800 9200 50  0001 C CNN
+	2    5800 9200
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+F 3 "~" H 4650 8500 50  0001 C CNN
+	1    4650 8500
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+F 3 "~" H 2450 9200 50  0001 C CNN
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+	0    1    1    0   
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+F 2 "" V 3080 8450 50  0001 C CNN
+F 3 "~" H 3150 8450 50  0001 C CNN
+	1    3150 8450
+	0    1    1    0   
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+	1    2700 9450
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+F 3 "" H 2700 9600 50  0001 C CNN
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+	1    0    0    -1  
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+Wire Wire Line
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+Wire Wire Line
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+Wire Wire Line
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+Wire Wire Line
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+Wire Wire Line
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+Wire Wire Line
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+Wire Wire Line
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+Wire Wire Line
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+F 2 "" V 1680 2500 50  0001 C CNN
+F 3 "~" H 1750 2500 50  0001 C CNN
+	1    1750 2500
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+Wire Wire Line
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+U 1 1 5FAA4C23
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+F 0 "R20" V 3843 9100 50  0000 C CNN
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+F 2 "" V 3980 9100 50  0001 C CNN
+F 3 "~" H 4050 9100 50  0001 C CNN
+	1    4050 9100
+	0    1    1    0   
+$EndComp
+Wire Wire Line
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+Wire Wire Line
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+L Device:R R19
+U 1 1 5FAC6B3E
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+F 0 "R19" V 4443 8900 50  0000 C CNN
+F 1 "22K" V 4534 8900 50  0000 C CNN
+F 2 "" V 4580 8900 50  0001 C CNN
+F 3 "~" H 4650 8900 50  0001 C CNN
+	1    4650 8900
+	0    1    1    0   
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+F 1 "100K" V 4844 8900 50  0000 C CNN
+F 2 "Potentiometer_THT:Potentiometer_Vishay_148-149_Single_Horizontal" H 5050 8900 50  0001 C CNN
+F 3 "~" H 5050 8900 50  0001 C CNN
+	1    5050 8900
+	0    -1   -1   0   
+$EndComp
+Wire Wire Line
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+Wire Wire Line
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+Wire Wire Line
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+Wire Wire Line
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+Wire Wire Line
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+Wire Wire Line
+	5150 8650 5150 8500
+Wire Wire Line
+	5150 8500 4800 8500
+Wire Wire Line
+	4800 8900 4900 8900
+$Comp
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+U 1 1 5FAF156D
+P 5400 9500
+F 0 "#PWR020" H 5400 9250 50  0001 C CNN
+F 1 "GNDREF" H 5405 9327 50  0000 C CNN
+F 2 "" H 5400 9500 50  0001 C CNN
+F 3 "" H 5400 9500 50  0001 C CNN
+	1    5400 9500
+	1    0    0    -1  
+$EndComp
+$Comp
+L power:GNDREF #PWR021
+U 1 1 5FAF1C49
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+F 0 "#PWR021" H 6400 9250 50  0001 C CNN
+F 1 "GNDREF" H 6405 9327 50  0000 C CNN
+F 2 "" H 6400 9500 50  0001 C CNN
+F 3 "" H 6400 9500 50  0001 C CNN
+	1    6400 9500
+	1    0    0    -1  
+$EndComp
+$Comp
+L Device:R R22
+U 1 1 5FAF225E
+P 6400 9250
+F 0 "R22" H 6470 9296 50  0000 L CNN
+F 1 "22K" H 6470 9205 50  0000 L CNN
+F 2 "" V 6330 9250 50  0001 C CNN
+F 3 "~" H 6400 9250 50  0001 C CNN
+	1    6400 9250
+	1    0    0    -1  
+$EndComp
+Wire Wire Line
+	6200 8650 6200 9000
+Wire Wire Line
+	6200 9200 6100 9200
+Wire Wire Line
+	5500 9300 5400 9300
+Wire Wire Line
+	5400 9300 5400 9500
+Wire Wire Line
+	5300 9100 5300 9200
+Connection ~ 5150 8650
+Wire Wire Line
+	4400 8900 4400 9100
+Wire Wire Line
+	4800 9200 5300 9200
+Wire Wire Line
+	3800 9100 3900 9100
+Connection ~ 3500 9000
+Wire Wire Line
+	4200 9100 4400 9100
+Connection ~ 6200 9000
+Wire Wire Line
+	6200 9000 6200 9200
+Wire Wire Line
+	6400 9000 6400 9100
+Wire Wire Line
+	6400 9400 6400 9500
+Wire Wire Line
+	4800 9200 4800 9100
+Wire Wire Line
+	4800 9100 4400 9100
+Connection ~ 4400 9100
+Wire Wire Line
+	3800 9100 3800 9000
+Wire Wire Line
+	3500 9000 3800 9000
+Text GLabel 6850 9000 2    50   Output ~ 0
+Stage
+Wire Wire Line
+	6200 9000 6400 9000
+Connection ~ 6400 9000
+Wire Wire Line
+	6400 9000 6850 9000
+$Comp
+L Amplifier_Operational:LM358 U3
+U 1 1 5FCC6AFD
+P 2700 5300
+F 0 "U3" H 2700 4933 50  0000 C CNN
+F 1 "LM833N" H 2700 5024 50  0000 C CNN
+F 2 "Package_DIP:DIP-8_W7.62mm" H 2700 5300 50  0001 C CNN
+F 3 "" H 2700 5300 50  0001 C CNN
+	1    2700 5300
+	1    0    0    1   
+$EndComp
+$Comp
+L power:GNDREF #PWR026
+U 1 1 5F93633D
+P 4150 10550
+F 0 "#PWR026" H 4150 10300 50  0001 C CNN
+F 1 "GNDREF" H 4155 10377 50  0000 C CNN
+F 2 "" H 4150 10550 50  0001 C CNN
+F 3 "" H 4150 10550 50  0001 C CNN
+	1    4150 10550
+	1    0    0    -1  
+$EndComp
+$Comp
+L power:GNDREF #PWR025
+U 1 1 5F9381DA
+P 3350 10550
+F 0 "#PWR025" H 3350 10300 50  0001 C CNN
+F 1 "GNDREF" H 3355 10377 50  0000 C CNN
+F 2 "" H 3350 10550 50  0001 C CNN
+F 3 "" H 3350 10550 50  0001 C CNN
+	1    3350 10550
+	1    0    0    -1  
+$EndComp
+$Comp
+L Device:C C15
+U 1 1 5F93A49E
+P 3350 10400
+F 0 "C15" H 3235 10354 50  0000 R CNN
+F 1 "100nF" H 3235 10445 50  0000 R CNN
+F 2 "" H 3388 10250 50  0001 C CNN
+F 3 "~" H 3350 10400 50  0001 C CNN
+	1    3350 10400
+	-1   0    0    1   
+$EndComp
+$Comp
+L Device:C C16
+U 1 1 5F93AE68
+P 4150 10400
+F 0 "C16" H 4035 10354 50  0000 R CNN
+F 1 "100nF" H 4035 10445 50  0000 R CNN
+F 2 "" H 4188 10250 50  0001 C CNN
+F 3 "~" H 4150 10400 50  0001 C CNN
+	1    4150 10400
+	-1   0    0    1   
+$EndComp
+Wire Wire Line
+	3350 10150 3450 10150
+Connection ~ 3350 10150
+Wire Wire Line
+	3350 10050 3350 10150
+Wire Wire Line
+	3350 10150 3350 10250
+Connection ~ 4150 10150
+Wire Wire Line
+	4150 10150 4150 10250
+Wire Wire Line
+	4150 10150 4150 10050
+Wire Wire Line
+	4050 10150 4150 10150
+$Comp
+L power:+15V #PWR024
+U 1 1 5F939835
+P 4150 10050
+F 0 "#PWR024" H 4150 9900 50  0001 C CNN
+F 1 "+15V" H 4165 10223 50  0000 C CNN
+F 2 "" H 4150 10050 50  0001 C CNN
+F 3 "" H 4150 10050 50  0001 C CNN
+	1    4150 10050
+	1    0    0    -1  
+$EndComp
+$Comp
+L power:-15V #PWR023
+U 1 1 5F938A79
+P 3350 10050
+F 0 "#PWR023" H 3350 10150 50  0001 C CNN
+F 1 "-15V" H 3365 10223 50  0000 C CNN
+F 2 "" H 3350 10050 50  0001 C CNN
+F 3 "" H 3350 10050 50  0001 C CNN
+	1    3350 10050
+	1    0    0    -1  
+$EndComp
+$Comp
+L Amplifier_Operational:LM358 U4
+U 3 1 5F92849F
+P 3750 10250
+F 0 "U4" V 3425 10250 50  0000 C CNN
+F 1 "LM833N" V 3516 10250 50  0000 C CNN
+F 2 "Package_DIP:DIP-8_W7.62mm" H 3750 10250 50  0001 C CNN
+F 3 "" H 3750 10250 50  0001 C CNN
+	3    3750 10250
+	0    1    1    0   
+$EndComp
+$Comp
+L power:GNDREF #PWR017
+U 1 1 5FCF1258
+P 5700 5300
+F 0 "#PWR017" H 5700 5050 50  0001 C CNN
+F 1 "GNDREF" H 5705 5127 50  0000 C CNN
+F 2 "" H 5700 5300 50  0001 C CNN
+F 3 "" H 5700 5300 50  0001 C CNN
+	1    5700 5300
+	1    0    0    -1  
+$EndComp
+$Comp
+L power:GNDREF #PWR016
+U 1 1 5FCF125E
+P 4900 5300
+F 0 "#PWR016" H 4900 5050 50  0001 C CNN
+F 1 "GNDREF" H 4905 5127 50  0000 C CNN
+F 2 "" H 4900 5300 50  0001 C CNN
+F 3 "" H 4900 5300 50  0001 C CNN
+	1    4900 5300
+	1    0    0    -1  
+$EndComp
+$Comp
+L Device:C C11
+U 1 1 5FCF1264
+P 4900 5150
+F 0 "C11" H 4785 5104 50  0000 R CNN
+F 1 "100nF" H 4785 5195 50  0000 R CNN
+F 2 "" H 4938 5000 50  0001 C CNN
+F 3 "~" H 4900 5150 50  0001 C CNN
+	1    4900 5150
+	-1   0    0    1   
+$EndComp
+$Comp
+L Device:C C12
+U 1 1 5FCF126A
+P 5700 5150
+F 0 "C12" H 5585 5104 50  0000 R CNN
+F 1 "100nF" H 5585 5195 50  0000 R CNN
+F 2 "" H 5738 5000 50  0001 C CNN
+F 3 "~" H 5700 5150 50  0001 C CNN
+	1    5700 5150
+	-1   0    0    1   
+$EndComp
+Wire Wire Line
+	4900 4900 5000 4900
+Connection ~ 4900 4900
+Wire Wire Line
+	4900 4800 4900 4900
+Wire Wire Line
+	4900 4900 4900 5000
+Connection ~ 5700 4900
+Wire Wire Line
+	5700 4900 5700 5000
+Wire Wire Line
+	5700 4900 5700 4800
+Wire Wire Line
+	5600 4900 5700 4900
+$Comp
+L power:+15V #PWR014
+U 1 1 5FCF1278
+P 5700 4800
+F 0 "#PWR014" H 5700 4650 50  0001 C CNN
+F 1 "+15V" H 5715 4973 50  0000 C CNN
+F 2 "" H 5700 4800 50  0001 C CNN
+F 3 "" H 5700 4800 50  0001 C CNN
+	1    5700 4800
+	1    0    0    -1  
+$EndComp
+$Comp
+L power:-15V #PWR013
+U 1 1 5FCF127E
+P 4900 4800
+F 0 "#PWR013" H 4900 4900 50  0001 C CNN
+F 1 "-15V" H 4915 4973 50  0000 C CNN
+F 2 "" H 4900 4800 50  0001 C CNN
+F 3 "" H 4900 4800 50  0001 C CNN
+	1    4900 4800
+	1    0    0    -1  
+$EndComp
+$Comp
+L Amplifier_Operational:LM358 U3
+U 3 1 5FCF1284
+P 5300 5000
+F 0 "U3" V 4975 5000 50  0000 C CNN
+F 1 "LM833N" V 5066 5000 50  0000 C CNN
+F 2 "Package_DIP:DIP-8_W7.62mm" H 5300 5000 50  0001 C CNN
+F 3 "" H 5300 5000 50  0001 C CNN
+	3    5300 5000
+	0    1    1    0   
+$EndComp
+Text GLabel 6800 2250 2    50   Output ~ 0
+Mic1
+Text GLabel 1150 4800 0    50   Input ~ 0
+Mic1
+Text GLabel 8350 2350 0    50   Input ~ 0
+Stage
+$Comp
+L Device:R R12
+U 1 1 5FD14A6B
+P 1750 4800
+F 0 "R12" V 1543 4800 50  0000 C CNN
+F 1 "22K" V 1634 4800 50  0000 C CNN
+F 2 "" V 1680 4800 50  0001 C CNN
+F 3 "~" H 1750 4800 50  0001 C CNN
+	1    1750 4800
+	0    1    1    0   
+$EndComp
+$Comp
+L Device:R R14
+U 1 1 5FD2515A
+P 1750 5150
+F 0 "R14" V 1543 5150 50  0000 C CNN
+F 1 "22K" V 1634 5150 50  0000 C CNN
+F 2 "" V 1680 5150 50  0001 C CNN
+F 3 "~" H 1750 5150 50  0001 C CNN
+	1    1750 5150
+	0    1    1    0   
+$EndComp
+$Comp
+L Device:R R16
+U 1 1 5FD258D7
+P 1750 5500
+F 0 "R16" V 1543 5500 50  0000 C CNN
+F 1 "22K" V 1634 5500 50  0000 C CNN
+F 2 "" V 1680 5500 50  0001 C CNN
+F 3 "~" H 1750 5500 50  0001 C CNN
+	1    1750 5500
+	0    1    1    0   
+$EndComp
+$Comp
+L Device:R R13
+U 1 1 5FD25F73
+P 2850 4800
+F 0 "R13" V 2643 4800 50  0000 C CNN
+F 1 "22K" V 2734 4800 50  0000 C CNN
+F 2 "" V 2780 4800 50  0001 C CNN
+F 3 "~" H 2850 4800 50  0001 C CNN
+	1    2850 4800
+	0    1    1    0   
+$EndComp
+$Comp
+L Device:C C10
+U 1 1 5FD269DB
+P 2550 4450
+F 0 "C10" V 2298 4450 50  0000 C CNN
+F 1 "22pF" V 2389 4450 50  0000 C CNN
+F 2 "" H 2588 4300 50  0001 C CNN
+F 3 "~" H 2550 4450 50  0001 C CNN
+	1    2550 4450
+	0    1    1    0   
+$EndComp
+$Comp
+L Device:C C13
+U 1 1 5FD26AFE
+P 3350 5300
+F 0 "C13" V 3098 5300 50  0000 C CNN
+F 1 "4.7pF" V 3189 5300 50  0000 C CNN
+F 2 "" H 3388 5150 50  0001 C CNN
+F 3 "~" H 3350 5300 50  0001 C CNN
+	1    3350 5300
+	0    1    1    0   
+$EndComp
+$Comp
+L Device:R R15
+U 1 1 5FD26ECA
+P 3750 5300
+F 0 "R15" V 3543 5300 50  0000 C CNN
+F 1 "47R" V 3634 5300 50  0000 C CNN
+F 2 "" V 3680 5300 50  0001 C CNN
+F 3 "~" H 3750 5300 50  0001 C CNN
+	1    3750 5300
+	0    1    1    0   
+$EndComp
+Text Notes 2700 5800 0    50   ~ 0
+Summing Module\nGain: 0 dB\nIf feedback res. is variable,\ngain can be -inf to 0 dB
+Wire Wire Line
+	1900 4800 2000 4800
+Wire Wire Line
+	2000 4800 2000 5150
+Wire Wire Line
+	2000 5150 1900 5150
+Wire Wire Line
+	2000 5150 2000 5200
+Wire Wire Line
+	2000 5500 1900 5500
+Connection ~ 2000 5150
+Wire Wire Line
+	2400 5200 2300 5200
+Wire Wire Line
+	2300 5200 2300 4800
+Wire Wire Line
+	2300 4800 2700 4800
+Wire Wire Line
+	5300 9100 5500 9100
+Wire Wire Line
+	5150 8650 6200 8650
+$Comp
+L power:GNDREF #PWR018
+U 1 1 5FD7D2A6
+P 2300 5600
+F 0 "#PWR018" H 2300 5350 50  0001 C CNN
+F 1 "GNDREF" H 2305 5427 50  0000 C CNN
+F 2 "" H 2300 5600 50  0001 C CNN
+F 3 "" H 2300 5600 50  0001 C CNN
+	1    2300 5600
+	1    0    0    -1  
+$EndComp
+Text Notes 13050 5300 0    50   ~ 0
+Line driver\nGain: 6 dB
+Wire Wire Line
+	2300 4800 2300 4450
+Wire Wire Line
+	2300 4450 2400 4450
+Connection ~ 2300 4800
+Wire Wire Line
+	3000 4800 3100 4800
+Wire Wire Line
+	3100 4800 3100 4450
+Wire Wire Line
+	3100 4450 2700 4450
+Wire Wire Line
+	3100 4800 3100 5300
+Wire Wire Line
+	3100 5300 3000 5300
+Connection ~ 3100 4800
+Connection ~ 3100 5300
+Wire Wire Line
+	3500 5300 3600 5300
+Wire Wire Line
+	3100 5300 3200 5300
+Wire Wire Line
+	2400 5400 2300 5400
+Wire Wire Line
+	2300 5400 2300 5600
+Wire Wire Line
+	1150 4800 1600 4800
+Wire Wire Line
+	2000 5200 2300 5200
+Connection ~ 2000 5200
+Wire Wire Line
+	2000 5200 2000 5500
+Connection ~ 2300 5200
+Text GLabel 4350 5000 2    50   Output ~ 0
+MicSum
+Wire Wire Line
+	4350 5000 4000 5000
+Wire Wire Line
+	4000 5300 3900 5300
+$Comp
+L power:GNDREF #PWR06
+U 1 1 5FFAA880
+P 11550 1450
+F 0 "#PWR06" H 11550 1200 50  0001 C CNN
+F 1 "GNDREF" H 11555 1277 50  0000 C CNN
+F 2 "" H 11550 1450 50  0001 C CNN
+F 3 "" H 11550 1450 50  0001 C CNN
+	1    11550 1450
+	1    0    0    -1  
+$EndComp
+$Comp
+L power:GNDREF #PWR05
+U 1 1 5FFAA886
+P 10750 1450
+F 0 "#PWR05" H 10750 1200 50  0001 C CNN
+F 1 "GNDREF" H 10755 1277 50  0000 C CNN
+F 2 "" H 10750 1450 50  0001 C CNN
+F 3 "" H 10750 1450 50  0001 C CNN
+	1    10750 1450
+	1    0    0    -1  
+$EndComp
+$Comp
+L Device:C C4
+U 1 1 5FFAA88C
+P 10750 1300
+F 0 "C4" H 10635 1254 50  0000 R CNN
+F 1 "100nF" H 10635 1345 50  0000 R CNN
+F 2 "" H 10788 1150 50  0001 C CNN
+F 3 "~" H 10750 1300 50  0001 C CNN
+	1    10750 1300
+	-1   0    0    1   
+$EndComp
+$Comp
+L Device:C C5
+U 1 1 5FFAA892
+P 11550 1300
+F 0 "C5" H 11435 1254 50  0000 R CNN
+F 1 "100nF" H 11435 1345 50  0000 R CNN
+F 2 "" H 11588 1150 50  0001 C CNN
+F 3 "~" H 11550 1300 50  0001 C CNN
+	1    11550 1300
+	-1   0    0    1   
+$EndComp
+Wire Wire Line
+	10750 1050 10850 1050
+Connection ~ 10750 1050
+Wire Wire Line
+	10750 950  10750 1050
+Wire Wire Line
+	10750 1050 10750 1150
+Connection ~ 11550 1050
+Wire Wire Line
+	11550 1050 11550 1150
+Wire Wire Line
+	11550 1050 11550 950 
+Wire Wire Line
+	11450 1050 11550 1050
+$Comp
+L power:+15V #PWR03
+U 1 1 5FFAA8A0
+P 11550 950
+F 0 "#PWR03" H 11550 800 50  0001 C CNN
+F 1 "+15V" H 11565 1123 50  0000 C CNN
+F 2 "" H 11550 950 50  0001 C CNN
+F 3 "" H 11550 950 50  0001 C CNN
+	1    11550 950 
+	1    0    0    -1  
+$EndComp
+$Comp
+L power:-15V #PWR02
+U 1 1 5FFAA8A6
+P 10750 950
+F 0 "#PWR02" H 10750 1050 50  0001 C CNN
+F 1 "-15V" H 10765 1123 50  0000 C CNN
+F 2 "" H 10750 950 50  0001 C CNN
+F 3 "" H 10750 950 50  0001 C CNN
+	1    10750 950 
+	1    0    0    -1  
+$EndComp
+$Comp
+L Amplifier_Operational:LM358 U1
+U 3 1 5FFAA8AC
+P 11150 1150
+F 0 "U1" V 10825 1150 50  0000 C CNN
+F 1 "LM833N" V 10916 1150 50  0000 C CNN
+F 2 "Package_DIP:DIP-8_W7.62mm" H 11150 1150 50  0001 C CNN
+F 3 "" H 11150 1150 50  0001 C CNN
+	3    11150 1150
+	0    1    1    0   
+$EndComp
+Text GLabel 8350 1550 0    50   Input ~ 0
+MicSum
+Text Notes 12200 2900 0    50   ~ 0
+Headphone driver\nGain: TODO
+Text GLabel 11650 4500 0    50   Input ~ 0
+MicSum
+Text GLabel 12250 2000 0    50   Input ~ 0
+Head1
+Text GLabel 11550 2000 2    50   Output ~ 0
+Head1
+$Comp
+L Amplifier_Operational:LM358 U1
+U 2 1 5FFF673D
+P 9900 2300
+F 0 "U1" H 9900 1933 50  0000 C CNN
+F 1 "LM833N" H 9900 2024 50  0000 C CNN
+F 2 "Package_DIP:DIP-8_W7.62mm" H 9900 2300 50  0001 C CNN
+F 3 "" H 9900 2300 50  0001 C CNN
+	2    9900 2300
+	1    0    0    1   
+$EndComp
+$Comp
+L Device:R R9
+U 1 1 5FFF6743
+P 8950 2350
+F 0 "R9" V 8743 2350 50  0000 C CNN
+F 1 "22K" V 8834 2350 50  0000 C CNN
+F 2 "" V 8880 2350 50  0001 C CNN
+F 3 "~" H 8950 2350 50  0001 C CNN
+	1    8950 2350
+	0    1    1    0   
+$EndComp
+$Comp
+L Device:R_POT R3
+U 1 1 5FFF6755
+P 10050 1600
+F 0 "R3" V 9935 1600 50  0000 C CNN
+F 1 "22K" V 9844 1600 50  0000 C CNN
+F 2 "Potentiometer_THT:Potentiometer_Vishay_148-149_Single_Horizontal" V 9980 1600 50  0001 C CNN
+F 3 "~" H 10050 1600 50  0001 C CNN
+	1    10050 1600
+	0    1    -1   0   
+$EndComp
+$Comp
+L Device:C C3
+U 1 1 5FFF675B
+P 9750 1250
+F 0 "C3" V 9498 1250 50  0000 C CNN
+F 1 "22pF" V 9589 1250 50  0000 C CNN
+F 2 "" H 9788 1100 50  0001 C CNN
+F 3 "~" H 9750 1250 50  0001 C CNN
+	1    9750 1250
+	0    1    1    0   
+$EndComp
+$Comp
+L Device:C C7
+U 1 1 5FFF6761
+P 10550 2300
+F 0 "C7" V 10298 2300 50  0000 C CNN
+F 1 "4.7pF" V 10389 2300 50  0000 C CNN
+F 2 "" H 10588 2150 50  0001 C CNN
+F 3 "~" H 10550 2300 50  0001 C CNN
+	1    10550 2300
+	0    1    1    0   
+$EndComp
+$Comp
+L Device:R R8
+U 1 1 5FFF6767
+P 10950 2300
+F 0 "R8" V 10743 2300 50  0000 C CNN
+F 1 "47R" V 10834 2300 50  0000 C CNN
+F 2 "" V 10880 2300 50  0001 C CNN
+F 3 "~" H 10950 2300 50  0001 C CNN
+	1    10950 2300
+	0    1    1    0   
+$EndComp
+Text Notes 9900 2800 0    50   ~ 0
+Summing Module\nGain: -inf to 0 dB
+Wire Wire Line
+	9100 1800 9200 1800
+Wire Wire Line
+	9200 2350 9100 2350
+Wire Wire Line
+	9500 1600 9900 1600
+$Comp
+L power:GNDREF #PWR010
+U 1 1 5FFF6777
+P 9500 2600
+F 0 "#PWR010" H 9500 2350 50  0001 C CNN
+F 1 "GNDREF" H 9505 2427 50  0000 C CNN
+F 2 "" H 9500 2600 50  0001 C CNN
+F 3 "" H 9500 2600 50  0001 C CNN
+	1    9500 2600
+	1    0    0    -1  
+$EndComp
+Wire Wire Line
+	9500 1600 9500 1250
+Wire Wire Line
+	9500 1250 9600 1250
+Connection ~ 9500 1600
+Wire Wire Line
+	10700 2300 10800 2300
+Wire Wire Line
+	9600 2400 9500 2400
+Wire Wire Line
+	9500 2400 9500 2600
+Wire Wire Line
+	11550 2000 11200 2000
+Wire Wire Line
+	11200 2000 11200 2300
+Wire Wire Line
+	11200 2300 11100 2300
+Wire Wire Line
+	9200 1800 9200 2200
+Wire Wire Line
+	4000 5000 4000 5300
+Wire Wire Line
+	9200 2200 9200 2350
+Connection ~ 9200 2200
+Wire Wire Line
+	9200 2200 9500 2200
+Wire Wire Line
+	10200 2300 10300 2300
+Wire Wire Line
+	10050 1450 10050 1400
+Wire Wire Line
+	10050 1400 10200 1400
+Wire Wire Line
+	9500 1600 9500 2200
+Wire Wire Line
+	9500 2200 9600 2200
+Wire Wire Line
+	10300 1400 10300 2300
+Connection ~ 10300 2300
+Wire Wire Line
+	10300 2300 10400 2300
+Wire Wire Line
+	9900 1250 10200 1250
+Wire Wire Line
+	10200 1250 10200 1400
+Connection ~ 10200 1400
+Wire Wire Line
+	10200 1400 10300 1400
+$Comp
+L Device:R_POT R4
+U 1 1 6016D9DA
+P 8950 1800
+F 0 "R4" H 8881 1754 50  0000 R CNN
+F 1 "22K" H 8881 1845 50  0000 R CNN
+F 2 "Potentiometer_THT:Potentiometer_Vishay_148-149_Single_Horizontal" V 8880 1800 50  0001 C CNN
+F 3 "~" H 8950 1800 50  0001 C CNN
+	1    8950 1800
+	1    0    0    1   
+$EndComp
+Wire Wire Line
+	8350 2350 8800 2350
+Wire Wire Line
+	8950 1550 8950 1650
+Wire Wire Line
+	8350 1550 8950 1550
+Connection ~ 9500 2200
+Wire Wire Line
+	1050 9000 1200 9000
+Wire Wire Line
+	1050 8800 1300 8800
+Wire Wire Line
+	1100 8900 1050 8900
+$Comp
+L Connector:XLR3_AudioJack3_Combo_Ground J4
+U 1 1 5F81E1F3
+P 1600 8900
+F 0 "J4" H 1582 9217 50  0000 C CNN
+F 1 "Stage Line-In" H 1582 9126 50  0000 C CNN
+F 2 "" H 1600 8900 50  0001 C CNN
+F 3 "https://www.neutrik.com/de/produkt/ncj6fa-h.pdf" H 1600 8900 50  0001 C CNN
+	1    1600 8900
+	1    0    0    -1  
+$EndComp
+Wire Wire Line
+	1300 8800 1300 8900
+Connection ~ 1300 8900
+Wire Wire Line
+	1300 8900 1300 9200
+Connection ~ 1900 8900
+$Comp
+L Connector:Conn_01x03_Male J5
+U 1 1 602993B3
+P 13250 9100
+F 0 "J5" H 13358 9381 50  0000 C CNN
+F 1 "Mains_PowerTwist" H 13358 9290 50  0000 C CNN
+F 2 "" H 13250 9100 50  0001 C CNN
+F 3 "https://www.neutrik.com/de/produkt/nac3mpa-1.pdf" H 13250 9100 50  0001 C CNN
+	1    13250 9100
+	1    0    0    -1  
+$EndComp
+$Comp
+L Converter_ACDC:TMLM04253 PS1
+U 1 1 6029F857
+P 14600 9100
+F 0 "PS1" H 14600 9467 50  0000 C CNN
+F 1 "TXL 035-1515D" H 14600 9376 50  0000 C CNN
+F 2 "" H 14600 8750 50  0001 C CNN
+F 3 "https://www.tracopower.com/de/model/txl-035-1515d" H 14600 9100 50  0001 C CNN
+	1    14600 9100
+	1    0    0    -1  
+$EndComp
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+L power:GNDREF #PWR028
+U 1 1 602A0CDE
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+F 0 "#PWR028" H 15600 8950 50  0001 C CNN
+F 1 "GNDREF" H 15605 9027 50  0000 C CNN
+F 2 "" H 15600 9200 50  0001 C CNN
+F 3 "" H 15600 9200 50  0001 C CNN
+	1    15600 9200
+	1    0    0    -1  
+$EndComp
+Wire Wire Line
+	13450 9200 13550 9200
+Wire Wire Line
+	13550 9200 13550 9400
+$Comp
+L power:+15V #PWR027
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+F 0 "#PWR027" H 15300 8750 50  0001 C CNN
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+F 2 "" H 15300 8900 50  0001 C CNN
+F 3 "" H 15300 8900 50  0001 C CNN
+	1    15300 8900
+	1    0    0    -1  
+$EndComp
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+L power:-15V #PWR029
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+P 15300 9300
+F 0 "#PWR029" H 15300 9400 50  0001 C CNN
+F 1 "-15V" H 15315 9473 50  0000 C CNN
+F 2 "" H 15300 9300 50  0001 C CNN
+F 3 "" H 15300 9300 50  0001 C CNN
+	1    15300 9300
+	-1   0    0    1   
+$EndComp
+$Comp
+L power:Earth_Protective #PWR030
+U 1 1 602C4CA6
+P 13550 9400
+F 0 "#PWR030" H 13800 9150 50  0001 C CNN
+F 1 "Earth_Protective" H 14000 9250 50  0001 C CNN
+F 2 "" H 13550 9300 50  0001 C CNN
+F 3 "~" H 13550 9300 50  0001 C CNN
+	1    13550 9400
+	1    0    0    -1  
+$EndComp
+Wire Wire Line
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+Wire Wire Line
+	15300 9200 15300 9300
+Wire Wire Line
+	15100 9000 15300 9000
+Wire Wire Line
+	15300 9000 15300 8900
+Wire Wire Line
+	15600 9100 15600 9200
+Wire Wire Line
+	14100 9200 14000 9200
+Wire Wire Line
+	14000 9200 14000 9100
+Wire Wire Line
+	14000 9100 13450 9100
+Wire Wire Line
+	13450 9000 14100 9000
+NoConn ~ 8950 1950
+NoConn ~ 5200 8900
+NoConn ~ 1600 5150
+NoConn ~ 1600 5500
+NoConn ~ 10200 1600
+NoConn ~ 2750 2300
+NoConn ~ 2850 2300
+NoConn ~ 2750 1700
+Wire Wire Line
+	15100 9100 15600 9100
+NoConn ~ 13250 9000
+NoConn ~ 13250 9100
+NoConn ~ 13250 9200
+Text Notes 5850 1250 0    50   ~ 0
+TODO: On-Air and Mute buttons
+Text Notes 8150 2700 0    50   ~ 0
+TODO: Try 10K or 100K poti\nwith matching feedback R
+$Comp
+L JBeyerstedt-Library:DRV134PA U5
+U 1 1 603FAC5E
+P 12750 4200
+F 0 "U5" H 13550 4687 60  0000 C CNN
+F 1 "DRV134PA" H 13550 4581 60  0000 C CNN
+F 2 "Package_DIP:DIP-8_W7.62mm" H 13550 4540 60  0001 C CNN
+F 3 "https://www.ti.com/lit/ds/symlink/drv134.pdf" H 13550 4581 60  0001 C CNN
+	1    12750 4200
+	1    0    0    -1  
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+L power:-15V #PWR0101
+U 1 1 6044025E
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+F 0 "#PWR0101" H 12650 5150 50  0001 C CNN
+F 1 "-15V" H 12665 5223 50  0000 C CNN
+F 2 "" H 12650 5050 50  0001 C CNN
+F 3 "" H 12650 5050 50  0001 C CNN
+	1    12650 5050
+	-1   0    0    1   
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+L power:+15V #PWR0102
+U 1 1 60441414
+P 12650 3950
+F 0 "#PWR0102" H 12650 3800 50  0001 C CNN
+F 1 "+15V" H 12665 4123 50  0000 C CNN
+F 2 "" H 12650 3950 50  0001 C CNN
+F 3 "" H 12650 3950 50  0001 C CNN
+	1    12650 3950
+	1    0    0    -1  
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+L power:GNDREF #PWR0103
+U 1 1 604420CE
+P 12150 4150
+F 0 "#PWR0103" H 12150 3900 50  0001 C CNN
+F 1 "GNDREF" H 12155 3977 50  0000 C CNN
+F 2 "" H 12150 4150 50  0001 C CNN
+F 3 "" H 12150 4150 50  0001 C CNN
+	1    12150 4150
+	1    0    0    -1  
+$EndComp
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+L power:GNDREF #PWR0104
+U 1 1 60442CD0
+P 12150 5050
+F 0 "#PWR0104" H 12150 4800 50  0001 C CNN
+F 1 "GNDREF" H 12155 4877 50  0000 C CNN
+F 2 "" H 12150 5050 50  0001 C CNN
+F 3 "" H 12150 5050 50  0001 C CNN
+	1    12150 5050
+	1    0    0    -1  
+$EndComp
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+L Device:C C18
+U 1 1 60444365
+P 12400 4950
+F 0 "C18" V 12148 4950 50  0000 C CNN
+F 1 "1uF" V 12239 4950 50  0000 C CNN
+F 2 "" H 12438 4800 50  0001 C CNN
+F 3 "~" H 12400 4950 50  0001 C CNN
+	1    12400 4950
+	0    1    1    0   
+$EndComp
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+L Device:C C17
+U 1 1 604659B0
+P 12400 4050
+F 0 "C17" V 12148 4050 50  0000 C CNN
+F 1 "1uF" V 12239 4050 50  0000 C CNN
+F 2 "" H 12438 3900 50  0001 C CNN
+F 3 "~" H 12400 4050 50  0001 C CNN
+	1    12400 4050
+	0    1    1    0   
+$EndComp
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+L power:GNDREF #PWR0105
+U 1 1 6049ECFC
+P 14450 5050
+F 0 "#PWR0105" H 14450 4800 50  0001 C CNN
+F 1 "GNDREF" H 14455 4877 50  0000 C CNN
+F 2 "" H 14450 5050 50  0001 C CNN
+F 3 "" H 14450 5050 50  0001 C CNN
+	1    14450 5050
+	1    0    0    -1  
+$EndComp
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+	14350 4950 14450 4950
+Wire Wire Line
+	14450 4950 14450 5050
+Wire Wire Line
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+Wire Wire Line
+	14350 4200 14450 4200
+Wire Wire Line
+	14450 4200 14450 4050
+Wire Wire Line
+	14450 4050 14350 4050
+Wire Wire Line
+	14350 4500 14450 4500
+Wire Wire Line
+	14450 4500 14450 4650
+Wire Wire Line
+	14450 4650 14350 4650
+Wire Wire Line
+	14450 4050 14900 4050
+Wire Wire Line
+	14900 4050 14900 4400
+Wire Wire Line
+	14900 4400 15000 4400
+Connection ~ 14450 4050
+Wire Wire Line
+	14450 4650 14900 4650
+Wire Wire Line
+	14900 4650 14900 4800
+Wire Wire Line
+	14900 4800 15300 4800
+Connection ~ 14450 4650
+Wire Wire Line
+	11650 4500 12750 4500
+Wire Wire Line
+	12550 4950 12650 4950
+Wire Wire Line
+	12650 4950 12650 5050
+Connection ~ 12650 4950
+Wire Wire Line
+	12650 4950 12750 4950
+Wire Wire Line
+	12250 4950 12150 4950
+Wire Wire Line
+	12150 4950 12150 5050
+Wire Wire Line
+	12150 4150 12150 4050
+Wire Wire Line
+	12150 4050 12250 4050
+Wire Wire Line
+	12550 4050 12650 4050
+Connection ~ 12650 4050
+Wire Wire Line
+	12650 4050 12750 4050
+Wire Wire Line
+	12650 3950 12650 4050
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+L JBeyerstedt-Library:INA134PA U6
+U 1 1 606D5988
+P 2350 6950
+F 0 "U6" H 3150 7437 60  0000 C CNN
+F 1 "INA134PA" H 3150 7331 60  0000 C CNN
+F 2 "Package_DIP:DIP-8_W7.62mm" H 3150 7290 60  0001 C CNN
+F 3 "https://www.ti.com/lit/ds/symlink/ina134.pdf" H 2350 6750 60  0001 C CNN
+	1    2350 6950
+	1    0    0    -1  
+$EndComp
+Wire Wire Line
+	3950 7150 4050 7150
+Wire Wire Line
+	4050 7150 4050 7400
+Wire Wire Line
+	4050 7400 3950 7400
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+L power:-15V #PWR0106
+U 1 1 606E64F7
+P 4050 7800
+F 0 "#PWR0106" H 4050 7900 50  0001 C CNN
+F 1 "-15V" H 4065 7973 50  0000 C CNN
+F 2 "" H 4050 7800 50  0001 C CNN
+F 3 "" H 4050 7800 50  0001 C CNN
+	1    4050 7800
+	1    0    0    1   
+$EndComp
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+L power:+15V #PWR0107
+U 1 1 606E64FD
+P 4050 6700
+F 0 "#PWR0107" H 4050 6550 50  0001 C CNN
+F 1 "+15V" H 4065 6873 50  0000 C CNN
+F 2 "" H 4050 6700 50  0001 C CNN
+F 3 "" H 4050 6700 50  0001 C CNN
+	1    4050 6700
+	-1   0    0    -1  
+$EndComp
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+L power:GNDREF #PWR0108
+U 1 1 606E6503
+P 4550 6900
+F 0 "#PWR0108" H 4550 6650 50  0001 C CNN
+F 1 "GNDREF" H 4555 6727 50  0000 C CNN
+F 2 "" H 4550 6900 50  0001 C CNN
+F 3 "" H 4550 6900 50  0001 C CNN
+	1    4550 6900
+	-1   0    0    -1  
+$EndComp
+$Comp
+L Device:C C20
+U 1 1 606E650F
+P 4300 7700
+F 0 "C20" V 4048 7700 50  0000 C CNN
+F 1 "1uF" V 4139 7700 50  0000 C CNN
+F 2 "" H 4338 7550 50  0001 C CNN
+F 3 "~" H 4300 7700 50  0001 C CNN
+	1    4300 7700
+	0    -1   1    0   
+$EndComp
+$Comp
+L Device:C C19
+U 1 1 606E6515
+P 4300 6800
+F 0 "C19" V 4048 6800 50  0000 C CNN
+F 1 "1uF" V 4139 6800 50  0000 C CNN
+F 2 "" H 4338 6650 50  0001 C CNN
+F 3 "~" H 4300 6800 50  0001 C CNN
+	1    4300 6800
+	0    -1   1    0   
+$EndComp
+Wire Wire Line
+	4050 7400 5150 7400
+Wire Wire Line
+	4150 7700 4050 7700
+Wire Wire Line
+	4050 7700 4050 7800
+Connection ~ 4050 7700
+Wire Wire Line
+	4050 7700 3950 7700
+Wire Wire Line
+	4450 7700 4550 7700
+Wire Wire Line
+	4550 7700 4550 7800
+Wire Wire Line
+	4550 6900 4550 6800
+Wire Wire Line
+	4550 6800 4450 6800
+Wire Wire Line
+	4150 6800 4050 6800
+Connection ~ 4050 6800
+Wire Wire Line
+	4050 6800 3950 6800
+Wire Wire Line
+	4050 6700 4050 6800
+Connection ~ 4050 7400
+$Comp
+L power:GNDREF #PWR0109
+U 1 1 606E6509
+P 4550 7800
+F 0 "#PWR0109" H 4550 7550 50  0001 C CNN
+F 1 "GNDREF" H 4555 7627 50  0000 C CNN
+F 2 "" H 4550 7800 50  0001 C CNN
+F 3 "" H 4550 7800 50  0001 C CNN
+	1    4550 7800
+	-1   0    0    -1  
+$EndComp
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+L power:GNDREF #PWR0110
+U 1 1 6073643F
+P 2250 7800
+F 0 "#PWR0110" H 2250 7550 50  0001 C CNN
+F 1 "GNDREF" H 2255 7627 50  0000 C CNN
+F 2 "" H 2250 7800 50  0001 C CNN
+F 3 "" H 2250 7800 50  0001 C CNN
+	1    2250 7800
+	-1   0    0    -1  
+$EndComp
+Wire Wire Line
+	2350 7700 2250 7700
+Wire Wire Line
+	2250 7700 2250 7800
+$Comp
+L Amplifier_Audio:LM386 U7
+U 1 1 6079E119
+P 13300 2000
+F 0 "U7" H 13644 2046 50  0000 L CNN
+F 1 "LM386N-4" H 13644 1955 50  0000 L CNN
+F 2 "" H 13400 2100 50  0001 C CNN
+F 3 "http://www.ti.com/lit/ds/symlink/lm386.pdf" H 13500 2200 50  0001 C CNN
+	1    13300 2000
+	1    0    0    -1  
+$EndComp
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+L power:GNDREF #PWR034
+U 1 1 607AFD33
+P 13000 2550
+F 0 "#PWR034" H 13000 2300 50  0001 C CNN
+F 1 "GNDREF" H 13005 2377 50  0000 C CNN
+F 2 "" H 13000 2550 50  0001 C CNN
+F 3 "" H 13000 2550 50  0001 C CNN
+	1    13000 2550
+	1    0    0    -1  
+$EndComp
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+L power:+15V #PWR031
+U 1 1 607B11F4
+P 13000 1600
+F 0 "#PWR031" H 13000 1450 50  0001 C CNN
+F 1 "+15V" H 13015 1773 50  0000 C CNN
+F 2 "" H 13000 1600 50  0001 C CNN
+F 3 "" H 13000 1600 50  0001 C CNN
+	1    13000 1600
+	1    0    0    -1  
+$EndComp
+$Comp
+L Device:CP C24
+U 1 1 607B2909
+P 13450 2650
+F 0 "C24" V 13705 2650 50  0000 C CNN
+F 1 "10uF" V 13614 2650 50  0000 C CNN
+F 2 "" H 13488 2500 50  0001 C CNN
+F 3 "~" H 13450 2650 50  0001 C CNN
+	1    13450 2650
+	0    -1   -1   0   
+$EndComp
+Wire Wire Line
+	13200 2400 13000 2400
+Wire Wire Line
+	13200 2300 13200 2400
+Wire Wire Line
+	13300 2300 13300 2650
+Wire Wire Line
+	13400 2300 13600 2300
+Wire Wire Line
+	13600 2300 13600 2650
+$Comp
+L Device:CP C22
+U 1 1 60836DA2
+P 14350 2000
+F 0 "C22" V 14605 2000 50  0000 C CNN
+F 1 "250pF" V 14514 2000 50  0000 C CNN
+F 2 "" H 14388 1850 50  0001 C CNN
+F 3 "~" H 14350 2000 50  0001 C CNN
+	1    14350 2000
+	0    -1   -1   0   
+$EndComp
+$Comp
+L power:GNDREF #PWR033
+U 1 1 6084D8C2
+P 12750 1800
+F 0 "#PWR033" H 12750 1550 50  0001 C CNN
+F 1 "GNDREF" H 12755 1627 50  0000 C CNN
+F 2 "" H 12750 1800 50  0001 C CNN
+F 3 "" H 12750 1800 50  0001 C CNN
+	1    12750 1800
+	1    0    0    -1  
+$EndComp
+$Comp
+L Device:R_POT R24
+U 1 1 6084E670
+P 12400 2250
+F 0 "R24" H 12331 2204 50  0000 R CNN
+F 1 "10K" H 12331 2295 50  0000 R CNN
+F 2 "Potentiometer_THT:Potentiometer_Vishay_148-149_Single_Horizontal" V 12330 2250 50  0001 C CNN
+F 3 "~" H 12400 2250 50  0001 C CNN
+	1    12400 2250
+	1    0    0    1   
+$EndComp
+$Comp
+L Device:C C23
+U 1 1 60871875
+P 14100 2250
+F 0 "C23" H 14215 2296 50  0000 L CNN
+F 1 "0.05uF" H 14215 2205 50  0000 L CNN
+F 2 "" H 14138 2100 50  0001 C CNN
+F 3 "~" H 14100 2250 50  0001 C CNN
+	1    14100 2250
+	1    0    0    -1  
+$EndComp
+$Comp
+L Device:R R25
+U 1 1 60872DD8
+P 14100 2550
+F 0 "R25" H 14170 2596 50  0000 L CNN
+F 1 "10K" H 14170 2505 50  0000 L CNN
+F 2 "" V 14030 2550 50  0001 C CNN
+F 3 "~" H 14100 2550 50  0001 C CNN
+	1    14100 2550
+	1    0    0    -1  
+$EndComp
+Wire Wire Line
+	13000 1900 13000 1750
+Wire Wire Line
+	13000 1750 12750 1750
+Wire Wire Line
+	12750 1750 12750 1800
+Wire Wire Line
+	13000 2100 12900 2100
+Wire Wire Line
+	12900 2250 12550 2250
+Wire Wire Line
+	12400 2400 12400 2500
+Wire Wire Line
+	12400 2500 13000 2500
+Wire Wire Line
+	12250 2000 12400 2000
+Wire Wire Line
+	12400 2000 12400 2100
+Wire Wire Line
+	13200 1600 13200 1700
+$Comp
+L Device:C C21
+U 1 1 60913A5C
+P 13550 1600
+F 0 "C21" V 13298 1600 50  0000 C CNN
+F 1 "10-100 uF" V 13389 1600 50  0000 C CNN
+F 2 "" H 13588 1450 50  0001 C CNN
+F 3 "~" H 13550 1600 50  0001 C CNN
+	1    13550 1600
+	0    1    1    0   
+$EndComp
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+L power:GNDREF #PWR032
+U 1 1 60915929
+P 13800 1600
+F 0 "#PWR032" H 13800 1350 50  0001 C CNN
+F 1 "GNDREF" H 13805 1427 50  0000 C CNN
+F 2 "" H 13800 1600 50  0001 C CNN
+F 3 "" H 13800 1600 50  0001 C CNN
+	1    13800 1600
+	1    0    0    -1  
+$EndComp
+Wire Wire Line
+	13400 1600 13300 1600
+Wire Wire Line
+	13300 1600 13300 1700
+Wire Wire Line
+	13700 1600 13800 1600
+Wire Wire Line
+	13000 1600 13200 1600
+Wire Wire Line
+	13600 2000 14100 2000
+Wire Wire Line
+	14100 2000 14100 2100
+Connection ~ 14100 2000
+Wire Wire Line
+	14100 2000 14200 2000
+Wire Wire Line
+	13000 2400 13000 2500
+Connection ~ 13000 2500
+Wire Wire Line
+	13000 2500 13000 2550
+Wire Wire Line
+	12900 2100 12900 2250
+$Comp
+L power:GNDREF #PWR035
+U 1 1 609E4DD0
+P 14100 2700
+F 0 "#PWR035" H 14100 2450 50  0001 C CNN
+F 1 "GNDREF" H 14105 2527 50  0000 C CNN
+F 2 "" H 14100 2700 50  0001 C CNN
+F 3 "" H 14100 2700 50  0001 C CNN
+	1    14100 2700
+	1    0    0    -1  
+$EndComp
+Wire Wire Line
+	14500 2000 14600 2000
+Wire Wire Line
+	14600 2000 14600 1900
+Wire Wire Line
+	14600 1800 15000 1800
+Wire Wire Line
+	15000 1900 14600 1900
+Connection ~ 14600 1900
+Wire Wire Line
+	14600 1800 14600 1900
+Text Notes 9950 7000 0    50   ~ 0
+TODO: VU Meter !!!!
+Text GLabel 8450 6600 0    50   Input ~ 0
+Mic1
+$Comp
+L Amplifier_Operational:LM358 U1
+U 1 1 60A8F329
+P 5350 2250
+F 0 "U1" H 5350 1883 50  0000 C CNN
+F 1 "LM833N" H 5350 1974 50  0000 C CNN
+F 2 "Package_DIP:DIP-8_W7.62mm" H 5350 2250 50  0001 C CNN
+F 3 "" H 5350 2250 50  0001 C CNN
+	1    5350 2250
+	1    0    0    1   
+$EndComp
+$Comp
+L Device:C C25
+U 1 1 60AA92C3
+P 5200 1150
+F 0 "C25" V 4948 1150 50  0000 C CNN
+F 1 "0.1uF" V 5039 1150 50  0000 C CNN
+F 2 "" H 5238 1000 50  0001 C CNN
+F 3 "~" H 5200 1150 50  0001 C CNN
+	1    5200 1150
+	0    1    1    0   
+$EndComp
+$Comp
+L Device:R R26
+U 1 1 60AAAB08
+P 5200 1550
+F 0 "R26" V 4993 1550 50  0000 C CNN
+F 1 "120R" V 5084 1550 50  0000 C CNN
+F 2 "" V 5130 1550 50  0001 C CNN
+F 3 "~" H 5200 1550 50  0001 C CNN
+	1    5200 1550
+	0    1    1    0   
+$EndComp
+$Comp
+L Device:R_POT R27
+U 1 1 60B0D55A
+P 5600 1550
+F 0 "R27" V 5485 1550 50  0000 C CNN
+F 1 "25K" V 5394 1550 50  0000 C CNN
+F 2 "Potentiometer_THT:Potentiometer_Vishay_148-149_Single_Horizontal" V 5530 1550 50  0001 C CNN
+F 3 "~" H 5600 1550 50  0001 C CNN
+	1    5600 1550
+	0    -1   -1   0   
+$EndComp
+$Comp
+L power:GNDREF #PWR0111
+U 1 1 60BBC462
+P 4950 2550
+F 0 "#PWR0111" H 4950 2300 50  0001 C CNN
+F 1 "GNDREF" H 4955 2377 50  0000 C CNN
+F 2 "" H 4950 2550 50  0001 C CNN
+F 3 "" H 4950 2550 50  0001 C CNN
+	1    4950 2550
+	1    0    0    -1  
+$EndComp
+Wire Wire Line
+	5050 1550 4950 1550
+Wire Wire Line
+	4950 2150 5050 2150
+Wire Wire Line
+	4950 1150 5050 1150
+Wire Wire Line
+	4950 1150 4950 1550
+Connection ~ 4950 1550
+Wire Wire Line
+	5350 1550 5450 1550
+Wire Wire Line
+	5350 1150 5700 1150
+Wire Wire Line
+	5700 1150 5700 1400
+Wire Wire Line
+	5700 1400 5600 1400
+Wire Wire Line
+	5700 1400 5850 1400
+Wire Wire Line
+	5850 1400 5850 2250
+Wire Wire Line
+	5850 2250 5650 2250
+Connection ~ 5700 1400
+Wire Wire Line
+	5850 2250 6800 2250
+Connection ~ 5850 2250
+Wire Wire Line
+	5050 2350 4950 2350
+Wire Wire Line
+	4950 2350 4950 2550
+Wire Wire Line
+	4950 1550 4950 2000
+Wire Wire Line
+	4500 2000 4950 2000
+Connection ~ 4950 2000
+Wire Wire Line
+	4950 2000 4950 2150
+$Comp
+L Switch:SW_Push_Open SW1
+U 1 1 60D151FD
+P 6050 1050
+F 0 "SW1" H 6050 1265 50  0000 C CNN
+F 1 "Mute_1" H 6050 1174 50  0000 C CNN
+F 2 "" H 6050 1250 50  0001 C CNN
+F 3 "~" H 6050 1250 50  0001 C CNN
+	1    6050 1050
+	1    0    0    -1  
+$EndComp
+$Comp
+L Switch:SW_SPST_LED SW2
+U 1 1 60D16A9A
+P 6750 1050
+F 0 "SW2" H 6750 1385 50  0000 C CNN
+F 1 "OnAir_1" H 6750 1294 50  0000 C CNN
+F 2 "" H 6750 1350 50  0001 C CNN
+F 3 "~" H 6750 1350 50  0001 C CNN
+	1    6750 1050
+	1    0    0    -1  
+$EndComp
+NoConn ~ 5750 1550
+$EndSCHEMATC