Merge development: PCB design fixes

2020-12-13 22:05:00 +01:00 · 2020-12-13 22:05:00 +01:00 · cdfdfbcc50
parent 6062153db0 d8e0d7cb9f
commit cdfdfbcc50
11 changed files with 5417 additions and 5552 deletions
--- a/README.md
+++ b/README.md
@ -42,9 +42,9 @@ This results in a signal flow like this: ![](docs/signal-flow.jpg)

 ### Tasks
 - [x] Requirements collection
- [ ] Electrical design draft/ proof of concept (breadboard)
- [ ] Proof of concept validation
- [ ] First PCB layout
+- [x] Electrical design draft/ proof of concept (breadboard)
+- [x] Proof of concept validation
+- [x] First PCB layout
 - [ ] More testing/ validation

 Help is always appreciated!
@ -55,7 +55,7 @@ Help is always appreciated!
 - [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
+- [x] VU meter (own PCB)
 - [ ] Mute and On-Air buttons


@ -76,8 +76,6 @@ But in our case we just need on/ off and some gain range to adjust for different

 TODO: Integrate the On-Air button with it's LEDs

-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.
@ -87,14 +85,18 @@ The second part of that circuit was taken from the [circuitlib audio mixer tutor

 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).

+The mixer design uses inverting op-amp circuits, because they require less components and signal routing.
+Normally an audio mixer should take care of adding signals in-phase, because otherwise two microphones might cancel each other out.
+In our case, there are just two types of summing: All microphones for the interpreter unit's line-out and the individual headphone mixes.
+Because the stage input is quite independent of the interpreter's microphones, no special phase/ inversion considerations are needed.
+And the microphones connected to our unit will experience the same inversions anyways.
+
 #### Line Output Driver
-TODO: Either use https://www.ti.com/product/DRV134 or http://www.thatcorp.com/1600-series_Balanced_Line_Driver_ICs.shtml.
+Line Output conversion is done by the [DRV134](https://www.ti.com/product/DRV134) IC.

 TODO: How to achieve galvanic isolation?

@ -104,8 +106,17 @@ The headphone output needs a maximum output power of about 0.1 W and should put
 For the first draft, we're using one LM386 audio power amplifier even though it has a quite high minimal amplification of factor 20.

 #### 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.
+When searching for VU meter circuits, many use the LM3916 LED bar graph driver, which already has the right scaling built in.
+But this chip is obsolete and not produced any more, so we designed our own chain of comperators to drive a set of LEDs.

+#### User Interface Hardware
+For the potentiometers, we first wanted to use ones with a conductive plastic resistor element for maximum longevity from Bourns, but these are hard to find with logarithmic scaling.
+An affordable and easily obtainable (Reichelt) alternative was found in the Alps RK11K and RK14K series.
+They are available in linear and logarithmic scale, as well as single (mono) and dual (stereo) units and have a nice feeling.
+
+Another potentiometer from Omeg was tried, but it had a "jump" in the resistor value at some knob positions.
+
+TODO: On-Air button


 ## Notes
@ -122,18 +133,65 @@ 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  |
+| Count | Art. No.            | Description         | Price |
+|-------|---------------------|---------------------|-------|
+| 1     | Neutrik NAC3 MPA-1  | Main Power Input    | 3,33  |
+| 1     | Neutrik NCJ 6 FAH   | Line Input          | 1,27  |
+| 1     | Neutrik NC3 MD-LX   | Line Output         | 3,22  |
+| 1     |  |  | TODO  |
+
+| 3x1   | Neutrik NC3 FD-LX   | Microphone Input    | 3,44  |
+| 3x1   | Neutrik NJ3 FP-6-C  | Headphone Output    | 5,40  |
+| 3x1   | TODO                | Mute Button         | TODO  |
+| 3x1   | TODO                | On-Air Button       | TODO  |
+| 3x4   | Alps RK11K1120-A503 | 50K log. Gain/ Vol. | 1,32  |
+| 3x1   | Alps RK14K12B0A0R   | 50K log. Vol. (st.) | 1,50  |
+| 1     | Vishay M64{Y,Z}104  | 100K Trim Pot.      | 0,95  |

 Sub-Components

-| Count | Art. No.           | Description      | Price  |
-|-------|--------------------|------------------|--------|
+| 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
+
+| Count | Art. No.            | Description         | Price |
+|-------|---------------------|---------------------|-------|
+| 3     | NE5534              | Low-noise Op-Amp    | 0,54  |
+| 8     | LM833               | Generic Op-Amp      | 0,88  |
+| 3     | LM386N-4            | Audio Power Amp     | 0,83  |
+| 1     | DRV143              | Line Driver         | 4,50  |
+| TODO  | TODO                | El. Capacitor       | TODO  |
+| TODO  | TODO                | Cer. Capacitor      | TODO  |
+| TODO  | TODO                | Resistor            | TODO  |
+
+VU Meter Components
+
+| Count | Art. No.            | Description         | Price |
+|-------|---------------------|---------------------|-------|
+| 1     | Vishay M64{Y,Z}104  | 50K Trim Pot.       | 0,95  |
+| 1     | LM833               | Generic Op-Amp      | 0,88  |
+| 2     | 1N4148              | Signal Diode        | 0,02  |
+| 1     | 1k Metal Film       | Resistor            | TODO  |
+| 1     | 3.9k Metal Film     | Resistor            | TODO  |
+| 1     | 47 uF               | El. Capacitor       | TODO  |
+| 1     | 100k Metal Film     | Resistor            | TODO  |
+| 3     | LM339               | Quad-Ch. Comperator | 0,29  |
+| 5     | 100 nF              | Cer. Capacitor      | TODO  |
+| 1     | 1 uF                | El. Capacitor       | TODO  |
+| 5     | Vishay TLHR 5404    | LED red             | 0,18  |
+| 4     | Vishay TLHY 5404    | LED yellow          | 0,14  |
+| 3     | Vishay TLHG 5404    | LED green           | 0,17  |
+| 12    | 390R                | Resistor            | TODO  |
+| 1     | 39R                 | Resistor            | TODO  |
+| 2     | 68R                 | Resistor            | TODO  |
+| 1     | 100R                | Resistor            | TODO  |
+| 1     | 150R                | Resistor            | TODO  |
+| 1     | 270R                | Resistor            | TODO  |
+| 1     | 390R                | Resistor            | TODO  |
+| 1     | 680R                | Resistor            | TODO  |
+| 1     | 1K                  | Resistor            | TODO  |
+| 1     | 1.5K                | Resistor            | TODO  |
+| 2     | 2.7K                | Resistor            | TODO  |
+| 1     | 3.9K                | Resistor            | TODO  |
--- a/c3lingo-mixer.pdf
+++ b/c3lingo-mixer.pdf
--- a/schematics/mixer/c3lingo-interpreter-unit-cache.lib
+++ b/schematics/mixer/c3lingo-interpreter-unit-cache.lib
@ -360,53 +360,6 @@ 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
-#
-# Jumper_Jumper_3_Bridged12
-#
-DEF Jumper_Jumper_3_Bridged12 JP 0 0 Y N 1 F N
-F0 "JP" -100 -100 50 H V C CNN
-F1 "Jumper_Jumper_3_Bridged12" 0 110 50 H V C CNN
-F2 "" 0 0 50 H I C CNN
-F3 "" 0 0 50 H I C CNN
-$FPLIST
- Jumper*
- TestPoint*3Pads*
- TestPoint*Bridge*
-$ENDFPLIST
-DRAW
-A -65 -50 89 1282 518 0 1 0 N -120 20 -10 20
-C -130 0 20 0 0 0 N
-C 0 0 20 0 0 0 N
-C 130 0 20 0 0 0 N
-P 2 0 1 0 0 -50 0 -20 N
-X A 1 -250 0 100 R 50 50 1 1 P
-X C 2 0 -150 100 U 50 50 1 1 I
-X B 3 250 0 100 L 50 50 1 1 P
-ENDDRAW
-ENDDEF
-#
 # Switch_SW_Push
 #
 DEF Switch_SW_Push SW 0 40 N N 1 F N
--- a/schematics/mixer/c3lingo-interpreter-unit.kicad_pcb
+++ b/schematics/mixer/c3lingo-interpreter-unit.kicad_pcb
--- a/schematics/mixer/c3lingo-interpreter-unit.pro
+++ b/schematics/mixer/c3lingo-interpreter-unit.pro
@ -1,4 +1,4 @@
-update=Thursday, 12 November 2020 at 23:33:32
+update=Sunday, 13 December 2020 at 21:49:58
 last_client=kicad
 [general]
 version=1
@ -242,7 +242,7 @@ dPairViaGap=0.25
 [schematic_editor]
 version=1
 PageLayoutDescrFile=
-PlotDirectoryName=
+PlotDirectoryName=../../
 SubpartIdSeparator=0
 SubpartFirstId=65
 NetFmtName=Pcbnew
--- a/schematics/mixer/c3lingo-interpreter-unit.sch
+++ b/schematics/mixer/c3lingo-interpreter-unit.sch
--- a/schematics/vu_meter/vu_meter-cache.lib
+++ b/schematics/vu_meter/vu_meter-cache.lib
@ -74,26 +74,29 @@ X V+ 3 -100 300 150 D 50 50 5 1 W
 ENDDRAW
 ENDDEF
 #
-# Connector_Conn_01x03_Male
+# Connector_Conn_01x04_Male
 #
-DEF Connector_Conn_01x03_Male J 0 40 Y N 1 F N
+DEF Connector_Conn_01x04_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
+F1 "Connector_Conn_01x04_Male" 0 -300 50 H V C CNN
 F2 "" 0 0 50 H I C CNN
 F3 "" 0 0 50 H I C CNN
 $FPLIST
 Connector*:*_1x??_*
 $ENDFPLIST
 DRAW
+S 34 -195 0 -205 1 1 6 F
 S 34 -95 0 -105 1 1 6 F
 S 34 5 0 -5 1 1 6 F
 S 34 105 0 95 1 1 6 F
+P 2 1 1 6 50 -200 34 -200 N
 P 2 1 1 6 50 -100 34 -100 N
 P 2 1 1 6 50 0 34 0 N
 P 2 1 1 6 50 100 34 100 N
 X Pin_1 1 200 100 150 L 50 50 1 1 P
 X Pin_2 2 200 0 150 L 50 50 1 1 P
 X Pin_3 3 200 -100 150 L 50 50 1 1 P
+X Pin_4 4 200 -200 150 L 50 50 1 1 P
 ENDDRAW
 ENDDEF
 #
@ -217,6 +220,21 @@ X 3 3 0 -150 50 U 50 50 1 1 P
 ENDDRAW
 ENDDEF
 #
+# Mechanical_MountingHole
+#
+DEF Mechanical_MountingHole H 0 40 Y Y 1 F N
+F0 "H" 0 200 50 H V C CNN
+F1 "Mechanical_MountingHole" 0 125 50 H V C CNN
+F2 "" 0 0 50 H I C CNN
+F3 "" 0 0 50 H I C CNN
+$FPLIST
+ MountingHole*
+$ENDFPLIST
+DRAW
+C 0 0 50 0 1 50 N
+ENDDRAW
+ENDDEF
+#
 # power_+15V
 #
 DEF power_+15V #PWR 0 0 Y Y 1 F P
@ -232,6 +250,19 @@ 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_GNDREF
 #
 DEF power_GNDREF #PWR 0 0 Y Y 1 F P
--- a/schematics/vu_meter/vu_meter.kicad_pcb
+++ b/schematics/vu_meter/vu_meter.kicad_pcb
--- a/schematics/vu_meter/vu_meter.pro
+++ b/schematics/vu_meter/vu_meter.pro
@ -1,4 +1,4 @@
-update=Thursday, 12 November 2020 at 23:38:27
+update=Sunday, 13 December 2020 at 21:47:42
 version=1
 last_client=kicad
 [general]
@ -12,16 +12,6 @@ NetIExt=net
 version=1
 LibDir=
 [eeschema/libraries]
-[schematic_editor]
-version=1
-PageLayoutDescrFile=
-PlotDirectoryName=
-SubpartIdSeparator=0
-SubpartFirstId=65
-NetFmtName=Pcbnew
-SpiceAjustPassiveValues=0
-LabSize=50
-ERC_TestSimilarLabels=1
 [pcbnew]
 version=1
 PageLayoutDescrFile=
@ -259,3 +249,13 @@ uViaDrill=0.1
 dPairWidth=0.2
 dPairGap=0.25
 dPairViaGap=0.25
+[schematic_editor]
+version=1
+PageLayoutDescrFile=
+PlotDirectoryName=../../
+SubpartIdSeparator=0
+SubpartFirstId=65
+NetFmtName=Pcbnew
+SpiceAjustPassiveValues=0
+LabSize=50
+ERC_TestSimilarLabels=1
--- a/schematics/vu_meter/vu_meter.sch
+++ b/schematics/vu_meter/vu_meter.sch
@ -5,10 +5,10 @@ $Descr A4 8268 11693 portrait
 encoding utf-8
 Sheet 1 1
 Title "VU Meter Module"
-Date "2020-11-12"
-Rev "v0.1"
+Date "2020-12-06"
+Rev "v0.2"
 Comp "Jannik Beyerstedt"
-Comment1 "Experimentation Prototype"
+Comment1 "Fixed Prototype"
 Comment2 ""
 Comment3 ""
 Comment4 ""
@ -22,7 +22,7 @@ AR Path="/5FA7BAE6/5FA97E57" Ref="U8"  Part="1"
 F 0 "U2" H 5600 1667 50  0000 C CNN
 F 1 "LM339" H 5600 1576 50  0000 C CNN
 F 2 "Package_DIP:DIP-14_W7.62mm_Socket_LongPads" H 5550 1400 50  0001 C CNN
-F 3 "https://www.st.com/resource/en/datasheet/lm139.pdf" H 5650 1500 50  0001 C CNN
+F 3 "https://www.ti.com/lit/ds/symlink/lm339.pdf" H 5650 1500 50  0001 C CNN
 	1    5600 1300
 	1    0    0    -1  
 $EndComp
@ -35,7 +35,7 @@ AR Path="/5FA7BAE6/5FA97E5D" Ref="U8"  Part="2"
 F 0 "U2" H 5600 2317 50  0000 C CNN
 F 1 "LM339" H 5600 2226 50  0000 C CNN
 F 2 "Package_DIP:DIP-14_W7.62mm_Socket_LongPads" H 5550 2050 50  0001 C CNN
-F 3 "https://www.st.com/resource/en/datasheet/lm139.pdf" H 5650 2150 50  0001 C CNN
+F 3 "https://www.ti.com/lit/ds/symlink/lm339.pdf" H 5650 2150 50  0001 C CNN
 	2    5600 1950
 	1    0    0    -1  
 $EndComp
@ -48,7 +48,7 @@ AR Path="/5FA7BAE6/5FA97E63" Ref="U8"  Part="3"
 F 0 "U2" H 5600 2967 50  0000 C CNN
 F 1 "LM339" H 5600 2876 50  0000 C CNN
 F 2 "Package_DIP:DIP-14_W7.62mm_Socket_LongPads" H 5550 2700 50  0001 C CNN
-F 3 "https://www.st.com/resource/en/datasheet/lm139.pdf" H 5650 2800 50  0001 C CNN
+F 3 "https://www.ti.com/lit/ds/symlink/lm339.pdf" H 5650 2800 50  0001 C CNN
 	3    5600 2600
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@ -61,7 +61,7 @@ AR Path="/5FA7BAE6/5FA97E69" Ref="U8"  Part="4"
 F 0 "U2" H 5600 3617 50  0000 C CNN
 F 1 "LM339" H 5600 3526 50  0000 C CNN
 F 2 "Package_DIP:DIP-14_W7.62mm_Socket_LongPads" H 5550 3350 50  0001 C CNN
-F 3 "https://www.st.com/resource/en/datasheet/lm139.pdf" H 5650 3450 50  0001 C CNN
+F 3 "https://www.ti.com/lit/ds/symlink/lm339.pdf" H 5650 3450 50  0001 C CNN
 	4    5600 3250
 	1    0    0    -1  
 $EndComp
@ -74,7 +74,7 @@ AR Path="/5FA7BAE6/5FA97E6F" Ref="U8"  Part="5"
 F 0 "U2" H 1158 1946 50  0000 L CNN
 F 1 "LM339" H 1158 1855 50  0000 L CNN
 F 2 "Package_DIP:DIP-14_W7.62mm_Socket_LongPads" H 1150 2000 50  0001 C CNN
-F 3 "https://www.st.com/resource/en/datasheet/lm139.pdf" H 1250 2100 50  0001 C CNN
+F 3 "https://www.ti.com/lit/ds/symlink/lm339.pdf" H 1250 2100 50  0001 C CNN
 	5    1200 1900
 	0    -1   -1   0   
 $EndComp
@ -181,7 +181,7 @@ AR Path="/5FA7BAE6/5FC107AB" Ref="U9"  Part="1"
 F 0 "U3" H 5600 4267 50  0000 C CNN
 F 1 "LM339" H 5600 4176 50  0000 C CNN
 F 2 "Package_DIP:DIP-14_W7.62mm_Socket_LongPads" H 5550 4000 50  0001 C CNN
-F 3 "https://www.st.com/resource/en/datasheet/lm139.pdf" H 5650 4100 50  0001 C CNN
+F 3 "https://www.ti.com/lit/ds/symlink/lm339.pdf" H 5650 4100 50  0001 C CNN
 	1    5600 3900
 	1    0    0    -1  
 $EndComp
@ -194,7 +194,7 @@ AR Path="/5FA7BAE6/5FC107B1" Ref="U9"  Part="2"
 F 0 "U3" H 5600 4917 50  0000 C CNN
 F 1 "LM339" H 5600 4826 50  0000 C CNN
 F 2 "Package_DIP:DIP-14_W7.62mm_Socket_LongPads" H 5550 4650 50  0001 C CNN
-F 3 "https://www.st.com/resource/en/datasheet/lm139.pdf" H 5650 4750 50  0001 C CNN
+F 3 "https://www.ti.com/lit/ds/symlink/lm339.pdf" H 5650 4750 50  0001 C CNN
 	2    5600 4550
 	1    0    0    -1  
 $EndComp
@ -207,7 +207,7 @@ AR Path="/5FA7BAE6/5FC107B7" Ref="U9"  Part="3"
 F 0 "U3" H 5600 5567 50  0000 C CNN
 F 1 "LM339" H 5600 5476 50  0000 C CNN
 F 2 "Package_DIP:DIP-14_W7.62mm_Socket_LongPads" H 5550 5300 50  0001 C CNN
-F 3 "https://www.st.com/resource/en/datasheet/lm139.pdf" H 5650 5400 50  0001 C CNN
+F 3 "https://www.ti.com/lit/ds/symlink/lm339.pdf" H 5650 5400 50  0001 C CNN
 	3    5600 5200
 	1    0    0    -1  
 $EndComp
@ -220,7 +220,7 @@ AR Path="/5FA7BAE6/5FC107BD" Ref="U9"  Part="4"
 F 0 "U3" H 5600 6217 50  0000 C CNN
 F 1 "LM339" H 5600 6126 50  0000 C CNN
 F 2 "Package_DIP:DIP-14_W7.62mm_Socket_LongPads" H 5550 5950 50  0001 C CNN
-F 3 "https://www.st.com/resource/en/datasheet/lm139.pdf" H 5650 6050 50  0001 C CNN
+F 3 "https://www.ti.com/lit/ds/symlink/lm339.pdf" H 5650 6050 50  0001 C CNN
 	4    5600 5850
 	1    0    0    -1  
 $EndComp
@ -327,7 +327,7 @@ AR Path="/5FA7BAE6/5FC17233" Ref="U10"  Part="1"
 F 0 "U4" H 5600 6867 50  0000 C CNN
 F 1 "LM339" H 5600 6776 50  0000 C CNN
 F 2 "Package_DIP:DIP-14_W7.62mm_Socket_LongPads" H 5550 6600 50  0001 C CNN
-F 3 "https://www.st.com/resource/en/datasheet/lm139.pdf" H 5650 6700 50  0001 C CNN
+F 3 "https://www.ti.com/lit/ds/symlink/lm339.pdf" H 5650 6700 50  0001 C CNN
 	1    5600 6500
 	1    0    0    -1  
 $EndComp
@ -340,7 +340,7 @@ AR Path="/5FA7BAE6/5FC17239" Ref="U10"  Part="2"
 F 0 "U4" H 5600 7517 50  0000 C CNN
 F 1 "LM339" H 5600 7426 50  0000 C CNN
 F 2 "Package_DIP:DIP-14_W7.62mm_Socket_LongPads" H 5550 7250 50  0001 C CNN
-F 3 "https://www.st.com/resource/en/datasheet/lm139.pdf" H 5650 7350 50  0001 C CNN
+F 3 "https://www.ti.com/lit/ds/symlink/lm339.pdf" H 5650 7350 50  0001 C CNN
 	2    5600 7150
 	1    0    0    -1  
 $EndComp
@ -353,7 +353,7 @@ AR Path="/5FA7BAE6/5FC1723F" Ref="U10"  Part="3"
 F 0 "U4" H 5600 8167 50  0000 C CNN
 F 1 "LM339" H 5600 8076 50  0000 C CNN
 F 2 "Package_DIP:DIP-14_W7.62mm_Socket_LongPads" H 5550 7900 50  0001 C CNN
-F 3 "https://www.st.com/resource/en/datasheet/lm139.pdf" H 5650 8000 50  0001 C CNN
+F 3 "https://www.ti.com/lit/ds/symlink/lm339.pdf" H 5650 8000 50  0001 C CNN
 	3    5600 7800
 	1    0    0    -1  
 $EndComp
@ -366,7 +366,7 @@ AR Path="/5FA7BAE6/5FC17245" Ref="U10"  Part="4"
 F 0 "U4" H 5600 8817 50  0000 C CNN
 F 1 "LM339" H 5600 8726 50  0000 C CNN
 F 2 "Package_DIP:DIP-14_W7.62mm_Socket_LongPads" H 5550 8550 50  0001 C CNN
-F 3 "https://www.st.com/resource/en/datasheet/lm139.pdf" H 5650 8650 50  0001 C CNN
+F 3 "https://www.ti.com/lit/ds/symlink/lm339.pdf" H 5650 8650 50  0001 C CNN
 	4    5600 8450
 	1    0    0    -1  
 $EndComp
@ -479,7 +479,7 @@ L Device:R R1
 U 1 1 5FC34754
 P 6500 1300
 F 0 "R1" V 6293 1300 50  0000 C CNN
-F 1 "R" V 6384 1300 50  0000 C CNN
+F 1 "390R" V 6384 1300 50  0000 C CNN
 F 2 "Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal" V 6430 1300 50  0001 C CNN
 F 3 "~" H 6500 1300 50  0001 C CNN
 	1    6500 1300
@ -492,7 +492,8 @@ P 6900 1300
 F 0 "D1" H 6893 1517 50  0000 C CNN
 F 1 "+12 rd" H 6893 1426 50  0000 C CNN
 F 2 "LED_THT:LED_D5.0mm" H 6900 1300 50  0001 C CNN
-F 3 "~" H 6900 1300 50  0001 C CNN
+F 3 "https://www.vishay.com/docs/83012/tlhg540.pdf" H 6900 1300 50  0001 C CNN
+F 4 "TLHR5405" H 6900 1300 50  0001 C CNN "Model"
 	1    6900 1300
 	1    0    0    -1  
 $EndComp
@ -507,7 +508,7 @@ L Device:R R2
 U 1 1 5FC543C3
 P 6500 1950
 F 0 "R2" V 6293 1950 50  0000 C CNN
-F 1 "R" V 6384 1950 50  0000 C CNN
+F 1 "390R" V 6384 1950 50  0000 C CNN
 F 2 "Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal" V 6430 1950 50  0001 C CNN
 F 3 "~" H 6500 1950 50  0001 C CNN
 	1    6500 1950
@ -520,7 +521,8 @@ P 6900 1950
 F 0 "D2" H 6893 2167 50  0000 C CNN
 F 1 "+8 ye" H 6893 2076 50  0000 C CNN
 F 2 "LED_THT:LED_D5.0mm" H 6900 1950 50  0001 C CNN
-F 3 "~" H 6900 1950 50  0001 C CNN
+F 3 "https://www.vishay.com/docs/83012/tlhg540.pdf" H 6900 1950 50  0001 C CNN
+F 4 "TLHY5405" H 6900 1950 50  0001 C CNN "Model"
 	1    6900 1950
 	1    0    0    -1  
 $EndComp
@ -537,7 +539,7 @@ L Device:R R3
 U 1 1 5FC583CA
 P 6500 2600
 F 0 "R3" V 6293 2600 50  0000 C CNN
-F 1 "R" V 6384 2600 50  0000 C CNN
+F 1 "390R" V 6384 2600 50  0000 C CNN
 F 2 "Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal" V 6430 2600 50  0001 C CNN
 F 3 "~" H 6500 2600 50  0001 C CNN
 	1    6500 2600
@ -550,7 +552,8 @@ P 6900 2600
 F 0 "D3" H 6893 2817 50  0000 C CNN
 F 1 "+4 ye" H 6893 2726 50  0000 C CNN
 F 2 "LED_THT:LED_D5.0mm" H 6900 2600 50  0001 C CNN
-F 3 "~" H 6900 2600 50  0001 C CNN
+F 3 "https://www.vishay.com/docs/83012/tlhg540.pdf" H 6900 2600 50  0001 C CNN
+F 4 "TLHY5405" H 6900 2600 50  0001 C CNN "Model"
 	1    6900 2600
 	1    0    0    -1  
 $EndComp
@ -567,7 +570,7 @@ L Device:R R4
 U 1 1 5FC5A209
 P 6500 3250
 F 0 "R4" V 6293 3250 50  0000 C CNN
-F 1 "R" V 6384 3250 50  0000 C CNN
+F 1 "390R" V 6384 3250 50  0000 C CNN
 F 2 "Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal" V 6430 3250 50  0001 C CNN
 F 3 "~" H 6500 3250 50  0001 C CNN
 	1    6500 3250
@ -580,7 +583,8 @@ P 6900 3250
 F 0 "D4" H 6893 3467 50  0000 C CNN
 F 1 "0 gn" H 6893 3376 50  0000 C CNN
 F 2 "LED_THT:LED_D5.0mm" H 6900 3250 50  0001 C CNN
-F 3 "~" H 6900 3250 50  0001 C CNN
+F 3 "https://www.vishay.com/docs/83012/tlhg540.pdf" H 6900 3250 50  0001 C CNN
+F 4 "TLHG5405" H 6900 3250 50  0001 C CNN "Model"
 	1    6900 3250
 	1    0    0    -1  
 $EndComp
@ -597,7 +601,7 @@ L Device:R R5
 U 1 1 5FC5C53F
 P 6500 3900
 F 0 "R5" V 6293 3900 50  0000 C CNN
-F 1 "R" V 6384 3900 50  0000 C CNN
+F 1 "390R" V 6384 3900 50  0000 C CNN
 F 2 "Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal" V 6430 3900 50  0001 C CNN
 F 3 "~" H 6500 3900 50  0001 C CNN
 	1    6500 3900
@ -610,7 +614,8 @@ P 6900 3900
 F 0 "D5" H 6893 4117 50  0000 C CNN
 F 1 "-4 gn" H 6893 4026 50  0000 C CNN
 F 2 "LED_THT:LED_D5.0mm" H 6900 3900 50  0001 C CNN
-F 3 "~" H 6900 3900 50  0001 C CNN
+F 3 "https://www.vishay.com/docs/83012/tlhg540.pdf" H 6900 3900 50  0001 C CNN
+F 4 "TLHG5405" H 6900 3900 50  0001 C CNN "Model"
 	1    6900 3900
 	1    0    0    -1  
 $EndComp
@ -627,7 +632,7 @@ L Device:R R6
 U 1 1 5FC5EA53
 P 6500 4550
 F 0 "R6" V 6293 4550 50  0000 C CNN
-F 1 "R" V 6384 4550 50  0000 C CNN
+F 1 "390R" V 6384 4550 50  0000 C CNN
 F 2 "Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal" V 6430 4550 50  0001 C CNN
 F 3 "~" H 6500 4550 50  0001 C CNN
 	1    6500 4550
@ -640,7 +645,8 @@ P 6900 4550
 F 0 "D6" H 6893 4767 50  0000 C CNN
 F 1 "-8 gn" H 6893 4676 50  0000 C CNN
 F 2 "LED_THT:LED_D5.0mm" H 6900 4550 50  0001 C CNN
-F 3 "~" H 6900 4550 50  0001 C CNN
+F 3 "https://www.vishay.com/docs/83012/tlhg540.pdf" H 6900 4550 50  0001 C CNN
+F 4 "TLHG5405" H 6900 4550 50  0001 C CNN "Model"
 	1    6900 4550
 	1    0    0    -1  
 $EndComp
@ -657,7 +663,7 @@ L Device:R R7
 U 1 1 5FC60D28
 P 6500 5200
 F 0 "R7" V 6293 5200 50  0000 C CNN
-F 1 "R" V 6384 5200 50  0000 C CNN
+F 1 "390R" V 6384 5200 50  0000 C CNN
 F 2 "Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal" V 6430 5200 50  0001 C CNN
 F 3 "~" H 6500 5200 50  0001 C CNN
 	1    6500 5200
@ -670,7 +676,8 @@ P 6900 5200
 F 0 "D7" H 6893 5417 50  0000 C CNN
 F 1 "-12 ye" H 6893 5326 50  0000 C CNN
 F 2 "LED_THT:LED_D5.0mm" H 6900 5200 50  0001 C CNN
-F 3 "~" H 6900 5200 50  0001 C CNN
+F 3 "https://www.vishay.com/docs/83012/tlhg540.pdf" H 6900 5200 50  0001 C CNN
+F 4 "TLHY5405" H 6900 5200 50  0001 C CNN "Model"
 	1    6900 5200
 	1    0    0    -1  
 $EndComp
@ -687,7 +694,7 @@ L Device:R R8
 U 1 1 5FC636D5
 P 6500 5850
 F 0 "R8" V 6293 5850 50  0000 C CNN
-F 1 "R" V 6384 5850 50  0000 C CNN
+F 1 "390R" V 6384 5850 50  0000 C CNN
 F 2 "Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal" V 6430 5850 50  0001 C CNN
 F 3 "~" H 6500 5850 50  0001 C CNN
 	1    6500 5850
@ -700,7 +707,8 @@ P 6900 5850
 F 0 "D8" H 6893 6067 50  0000 C CNN
 F 1 "-16 ye" H 6893 5976 50  0000 C CNN
 F 2 "LED_THT:LED_D5.0mm" H 6900 5850 50  0001 C CNN
-F 3 "~" H 6900 5850 50  0001 C CNN
+F 3 "https://www.vishay.com/docs/83012/tlhg540.pdf" H 6900 5850 50  0001 C CNN
+F 4 "TLHY5405" H 6900 5850 50  0001 C CNN "Model"
 	1    6900 5850
 	1    0    0    -1  
 $EndComp
@ -717,7 +725,7 @@ L Device:R R9
 U 1 1 5FC66851
 P 6500 6500
 F 0 "R9" V 6293 6500 50  0000 C CNN
-F 1 "R" V 6384 6500 50  0000 C CNN
+F 1 "390R" V 6384 6500 50  0000 C CNN
 F 2 "Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal" V 6430 6500 50  0001 C CNN
 F 3 "~" H 6500 6500 50  0001 C CNN
 	1    6500 6500
@ -730,7 +738,8 @@ P 6900 6500
 F 0 "D9" H 6893 6717 50  0000 C CNN
 F 1 "-20 rd" H 6893 6626 50  0000 C CNN
 F 2 "LED_THT:LED_D5.0mm" H 6900 6500 50  0001 C CNN
-F 3 "~" H 6900 6500 50  0001 C CNN
+F 3 "https://www.vishay.com/docs/83012/tlhg540.pdf" H 6900 6500 50  0001 C CNN
+F 4 "TLHR5405" H 6900 6500 50  0001 C CNN "Model"
 	1    6900 6500
 	1    0    0    -1  
 $EndComp
@ -747,7 +756,7 @@ L Device:R R10
 U 1 1 5FC694C3
 P 6500 7150
 F 0 "R10" V 6293 7150 50  0000 C CNN
-F 1 "R" V 6384 7150 50  0000 C CNN
+F 1 "390R" V 6384 7150 50  0000 C CNN
 F 2 "Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal" V 6430 7150 50  0001 C CNN
 F 3 "~" H 6500 7150 50  0001 C CNN
 	1    6500 7150
@ -760,7 +769,8 @@ P 6900 7150
 F 0 "D10" H 6893 7367 50  0000 C CNN
 F 1 "-24 rd" H 6893 7276 50  0000 C CNN
 F 2 "LED_THT:LED_D5.0mm" H 6900 7150 50  0001 C CNN
-F 3 "~" H 6900 7150 50  0001 C CNN
+F 3 "https://www.vishay.com/docs/83012/tlhg540.pdf" H 6900 7150 50  0001 C CNN
+F 4 "TLHR5405" H 6900 7150 50  0001 C CNN "Model"
 	1    6900 7150
 	1    0    0    -1  
 $EndComp
@ -777,7 +787,7 @@ L Device:R R11
 U 1 1 5FC6C36E
 P 6500 7800
 F 0 "R11" V 6293 7800 50  0000 C CNN
-F 1 "R" V 6384 7800 50  0000 C CNN
+F 1 "390R" V 6384 7800 50  0000 C CNN
 F 2 "Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal" V 6430 7800 50  0001 C CNN
 F 3 "~" H 6500 7800 50  0001 C CNN
 	1    6500 7800
@ -790,7 +800,8 @@ P 6900 7800
 F 0 "D11" H 6893 8017 50  0000 C CNN
 F 1 "-28 rd" H 6893 7926 50  0000 C CNN
 F 2 "LED_THT:LED_D5.0mm" H 6900 7800 50  0001 C CNN
-F 3 "~" H 6900 7800 50  0001 C CNN
+F 3 "https://www.vishay.com/docs/83012/tlhg540.pdf" H 6900 7800 50  0001 C CNN
+F 4 "TLHR5405" H 6900 7800 50  0001 C CNN "Model"
 	1    6900 7800
 	1    0    0    -1  
 $EndComp
@ -807,7 +818,7 @@ L Device:R R12
 U 1 1 5FC6F375
 P 6500 8450
 F 0 "R12" V 6293 8450 50  0000 C CNN
-F 1 "R" V 6384 8450 50  0000 C CNN
+F 1 "390R" V 6384 8450 50  0000 C CNN
 F 2 "Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal" V 6430 8450 50  0001 C CNN
 F 3 "~" H 6500 8450 50  0001 C CNN
 	1    6500 8450
@ -820,7 +831,8 @@ P 6900 8450
 F 0 "D12" H 6893 8667 50  0000 C CNN
 F 1 "-32 rd" H 6893 8576 50  0000 C CNN
 F 2 "LED_THT:LED_D5.0mm" H 6900 8450 50  0001 C CNN
-F 3 "~" H 6900 8450 50  0001 C CNN
+F 3 "https://www.vishay.com/docs/83012/tlhg540.pdf" H 6900 8450 50  0001 C CNN
+F 4 "TLHR5405" H 6900 8450 50  0001 C CNN "Model"
 	1    6900 8450
 	1    0    0    -1  
 $EndComp
@ -833,7 +845,7 @@ Wire Wire Line
 Wire Wire Line
 	7150 7800 7150 8450
 Text Notes 1650 8750 0    50   ~ 0
-Buffer/ Rectifier\nGain: 4
+Buffer/ Rectifier\nGain: 3.9
 Text Notes 7650 1300 2    50   ~ 0
 +12 dBu
 Text Notes 7650 1950 2    50   ~ 0
@ -875,7 +887,7 @@ P 1200 3400
 F 0 "U3" H 1158 3446 50  0000 L CNN
 F 1 "LM339" H 1158 3355 50  0000 L CNN
 F 2 "Package_DIP:DIP-14_W7.62mm_Socket_LongPads" H 1150 3500 50  0001 C CNN
-F 3 "https://www.st.com/resource/en/datasheet/lm139.pdf" H 1250 3600 50  0001 C CNN
+F 3 "https://www.ti.com/lit/ds/symlink/lm339.pdf" H 1250 3600 50  0001 C CNN
 	5    1200 3400
 	0    -1   -1   0   
 $EndComp
@ -886,7 +898,7 @@ P 1200 4900
 F 0 "U4" H 1158 4946 50  0000 L CNN
 F 1 "LM339" H 1158 4855 50  0000 L CNN
 F 2 "Package_DIP:DIP-14_W7.62mm_Socket_LongPads" H 1150 5000 50  0001 C CNN
-F 3 "https://www.st.com/resource/en/datasheet/lm139.pdf" H 1250 5100 50  0001 C CNN
+F 3 "https://www.ti.com/lit/ds/symlink/lm339.pdf" H 1250 5100 50  0001 C CNN
 	5    1200 4900
 	0    -1   -1   0   
 $EndComp
@ -928,7 +940,7 @@ L Device:CP C6
 U 1 1 5FD7B3EC
 P 4350 9350
 F 0 "C6" H 4468 9396 50  0000 L CNN
-F 1 "2.2uF" H 4468 9305 50  0000 L CNN
+F 1 "47uF" H 4468 9305 50  0000 L CNN
 F 2 "Capacitor_THT:CP_Radial_D10.0mm_P2.50mm_P5.00mm" H 4388 9200 50  0001 C CNN
 F 3 "~" H 4350 9350 50  0001 C CNN
 	1    4350 9350
@ -939,7 +951,7 @@ L Device:R R15
 U 1 1 5FD7BF84
 P 4850 9350
 F 0 "R15" H 4920 9396 50  0000 L CNN
-F 1 "10K" H 4920 9305 50  0000 L CNN
+F 1 "100K" H 4920 9305 50  0000 L CNN
 F 2 "Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal" V 4780 9350 50  0001 C CNN
 F 3 "~" H 4850 9350 50  0001 C CNN
 	1    4850 9350
@ -950,7 +962,7 @@ Wire Wire Line
 Wire Wire Line
 	5200 7900 5200 8550
 Text Notes 4900 9750 0    50   ~ 0
-Signal Smoothing\n(Try out different values)
+Signal Smoothing\nTODO: Remove all together!?
 Connection ~ 4350 9100
 $Comp
 L Amplifier_Operational:LM358 U1
@ -961,7 +973,7 @@ AR Path="/5FA7BAE6/5FCB34F7" Ref="U14"  Part="3"
 F 0 "U1" V 1425 7100 50  0000 C CNN
 F 1 "LM833N" V 1516 7100 50  0000 C CNN
 F 2 "Package_DIP:DIP-8_W7.62mm_Socket_LongPads" H 1750 7100 50  0001 C CNN
-F 3 "" H 1750 7100 50  0001 C CNN
+F 3 "https://www.ti.com/lit/ds/symlink/lm833.pdf" H 1750 7100 50  0001 C CNN
 	3    1750 7100
 	0    1    1    0   
 $EndComp
@ -973,7 +985,7 @@ AR Path="/5FCB34DD" Ref="C1"  Part="1"
 AR Path="/5FA7BAE6/5FCB34DD" Ref="C28"  Part="1" 
 F 0 "C1" H 1935 7204 50  0000 R CNN
 F 1 "100nF" H 1935 7295 50  0000 R CNN
-F 2 "Capacitor_THT:C_Disc_D5.0mm_W2.5mm_P2.50mm" H 2088 7100 50  0001 C CNN
+F 2 "Capacitor_THT:C_Disc_D5.0mm_W2.5mm_P5.00mm" H 2088 7100 50  0001 C CNN
 F 3 "~" H 2050 7250 50  0001 C CNN
 	1    2050 7250
 	-1   0    0    1   
@ -1051,8 +1063,9 @@ U 1 1 5FCFBEFC
 P 1350 8250
 F 0 "RV1" H 1281 8296 50  0000 R CNN
 F 1 "50K" H 1281 8205 50  0000 R CNN
-F 2 "Potentiometer_THT:Potentiometer_Vishay_148-149_Single_Horizontal" H 1350 8250 50  0001 C CNN
-F 3 "~" H 1350 8250 50  0001 C CNN
+F 2 "Potentiometer_THT:Potentiometer_Vishay_T73XX_Horizontal" H 1350 8250 50  0001 C CNN
+F 3 "https://www.vishay.com/docs/57028/64.pdf" H 1350 8250 50  0001 C CNN
+F 4 "Vishay M64{Y,Z}503K" H 1350 8250 50  0001 C CNN "Model"
 	1    1350 8250
 	1    0    0    -1  
 $EndComp
@ -1080,7 +1093,7 @@ AR Path="/5FA7BAE6/5FCB34FE" Ref="U14"  Part="1"
 F 0 "U1" H 2900 7983 50  0000 C CNN
 F 1 "LM833N" H 2900 8074 50  0000 C CNN
 F 2 "Package_DIP:DIP-8_W7.62mm_Socket_LongPads" H 2900 8350 50  0001 C CNN
-F 3 "" H 2900 8350 50  0001 C CNN
+F 3 "https://www.ti.com/lit/ds/symlink/lm833.pdf" H 2900 8350 50  0001 C CNN
 	1    2900 8350
 	1    0    0    1   
 $EndComp
@ -1089,7 +1102,7 @@ L Device:CP C5
 U 1 1 5FEAE431
 P 1750 8250
 F 0 "C5" V 2005 8250 50  0000 C CNN
-F 1 "10uF" V 1914 8250 50  0000 C CNN
+F 1 "1uF" V 1914 8250 50  0000 C CNN
 F 2 "Capacitor_THT:CP_Radial_D5.0mm_P2.50mm" H 1788 8100 50  0001 C CNN
 F 3 "~" H 1750 8250 50  0001 C CNN
 	1    1750 8250
@ -1152,52 +1165,23 @@ U 1 1 5FABB7BB
 P 900 2250
 F 0 "C2" H 1015 2296 50  0000 L CNN
 F 1 "100nF" H 1015 2205 50  0000 L CNN
-F 2 "Capacitor_THT:C_Disc_D5.0mm_W2.5mm_P2.50mm" H 938 2100 50  0001 C CNN
+F 2 "Capacitor_THT:C_Disc_D5.0mm_W2.5mm_P5.00mm" H 938 2100 50  0001 C CNN
 F 3 "~" H 900 2250 50  0001 C CNN
 	1    900  2250
 	1    0    0    -1  
 $EndComp
 $Comp
-L Connector:Conn_01x03_Male J1
+L Connector:Conn_01x04_Male J1
 U 1 1 5FABC0AB
 P 800 1000
 F 0 "J1" H 908 1281 50  0000 C CNN
 F 1 "Pwr_Signal" H 908 1190 50  0000 C CNN
-F 2 "Connector_PinHeader_2.54mm:PinHeader_1x03_P2.54mm_Vertical" H 800 1000 50  0001 C CNN
+F 2 "Connector_PinHeader_2.54mm:PinHeader_1x04_P2.54mm_Vertical" H 800 1000 50  0001 C CNN
 F 3 "~" H 800 1000 50  0001 C CNN
+F 4 "TODO: Actual Connector" H 800 1000 50  0001 C CNN "Model"
 	1    800  1000
-	1    0    0    -1  
+	1    0    0    1   
 $EndComp
-$Comp
-L power:GNDREF #PWR013
-U 1 1 5FABEB24
-P 1500 1200
-F 0 "#PWR013" H 1500 950 50  0001 C CNN
-F 1 "GNDREF" H 1505 1027 50  0000 C CNN
-F 2 "" H 1500 1200 50  0001 C CNN
-F 3 "" H 1500 1200 50  0001 C CNN
-	1    1500 1200
-	1    0    0    -1  
-$EndComp
-$Comp
-L power:+15V #PWR012
-U 1 1 5FABF9E5
-P 1500 800
-F 0 "#PWR012" H 1500 650 50  0001 C CNN
-F 1 "+15V" H 1515 973 50  0000 C CNN
-F 2 "" H 1500 800 50  0001 C CNN
-F 3 "" H 1500 800 50  0001 C CNN
-	1    1500 800 
-	1    0    0    -1  
-$EndComp
-Wire Wire Line
-	1000 900  1250 900 
-Wire Wire Line
-	1500 900  1500 800 
-Wire Wire Line
-	1000 1100 1250 1100
-Wire Wire Line
-	1500 1100 1500 1200
 Text GLabel 1000 8000 0    50   Input ~ 0
 Line_Input
 $Comp
@ -1271,7 +1255,7 @@ U 1 1 5FBCBB9A
 P 900 3750
 F 0 "C3" H 1015 3796 50  0000 L CNN
 F 1 "100nF" H 1015 3705 50  0000 L CNN
-F 2 "Capacitor_THT:C_Disc_D5.0mm_W2.5mm_P2.50mm" H 938 3600 50  0001 C CNN
+F 2 "Capacitor_THT:C_Disc_D5.0mm_W2.5mm_P5.00mm" H 938 3600 50  0001 C CNN
 F 3 "~" H 900 3750 50  0001 C CNN
 	1    900  3750
 	1    0    0    -1  
@ -1342,17 +1326,13 @@ Wire Wire Line
 Wire Wire Line
 	5000 1100 5000 1200
 Connection ~ 5000 1200
-Text GLabel 1600 1000 2    50   Output ~ 0
-Line_Input
-Wire Wire Line
-	1000 1000 1600 1000
 $Comp
 L Device:C C4
 U 1 1 5FC56400
 P 900 5250
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 F 1 "100nF" H 1015 5205 50  0000 L CNN
-F 2 "Capacitor_THT:C_Disc_D5.0mm_W2.5mm_P2.50mm" H 938 5100 50  0001 C CNN
+F 2 "Capacitor_THT:C_Disc_D5.0mm_W2.5mm_P5.00mm" H 938 5100 50  0001 C CNN
 F 3 "~" H 900 5250 50  0001 C CNN
 	1    900  5250
 	1    0    0    -1  
@ -1426,43 +1406,181 @@ F 3 "" H 2050 7500 50  0001 C CNN
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 	1    0    0    -1  
 $EndComp
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 Wire Wire Line
 	2050 7000 2050 7100
 Wire Wire Line
 	2050 7400 2050 7500
 Text Notes 3500 3350 0    50   ~ 0
 For Input Gain of 3.9:\n2700 Ω: 11,99 dBu\n3900 Ω: 8,12 dBu\n2700 Ω: 3,86 dBu\n1500 Ω: 0,1 dBu\n1000 Ω: -3,8 dBu\n680 Ω: -8,03 dBu\n390 Ω: -11,89 dBu\n270 Ω: -16,17 dBu\n150 Ω: -19,95 dBu\n100 Ω: -23,87 dBu\n68 Ω: -28,15 dBu\n39 Ω: -32,08 dBu\n68 Ω to ground\n\n1.11 mA @ 15V\n(13.565 kΩ)
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-L power:PWR_FLAG #FLG0101
-U 1 1 5FECA14D
-P 1250 900
-F 0 "#FLG0101" H 1250 975 50  0001 C CNN
-F 1 "PWR_FLAG" H 1250 1073 50  0000 C CNN
-F 2 "" H 1250 900 50  0001 C CNN
-F 3 "~" H 1250 900 50  0001 C CNN
-	1    1250 900 
-	1    0    0    -1  
-$EndComp
-Connection ~ 1250 900 
-Wire Wire Line
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 Wire Wire Line
 	2050 6900 2050 7000
 Connection ~ 2050 7000
 $Comp
+L Mechanical:MountingHole H1
+U 1 1 5FB7453C
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+F 0 "H1" H 950 10346 50  0000 L CNN
+F 1 "MountingHole" H 950 10255 50  0000 L CNN
+F 2 "MountingHole:MountingHole_3.2mm_M3_ISO14580" H 850 10300 50  0001 C CNN
+F 3 "~" H 850 10300 50  0001 C CNN
+	1    850  10300
+	1    0    0    -1  
+$EndComp
+$Comp
+L Mechanical:MountingHole H3
+U 1 1 5FB8138C
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+F 0 "H3" H 950 10596 50  0000 L CNN
+F 1 "MountingHole" H 950 10505 50  0000 L CNN
+F 2 "MountingHole:MountingHole_3.2mm_M3_ISO14580" H 850 10550 50  0001 C CNN
+F 3 "~" H 850 10550 50  0001 C CNN
+	1    850  10550
+	1    0    0    -1  
+$EndComp
+$Comp
+L Mechanical:MountingHole H2
+U 1 1 5FB81634
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+F 0 "H2" H 1850 10346 50  0000 L CNN
+F 1 "MountingHole" H 1850 10255 50  0000 L CNN
+F 2 "MountingHole:MountingHole_3.2mm_M3_ISO14580" H 1750 10300 50  0001 C CNN
+F 3 "~" H 1750 10300 50  0001 C CNN
+	1    1750 10300
+	1    0    0    -1  
+$EndComp
+$Comp
+L Mechanical:MountingHole H4
+U 1 1 5FB8197A
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+F 0 "H4" H 1850 10596 50  0000 L CNN
+F 1 "MountingHole" H 1850 10505 50  0000 L CNN
+F 2 "MountingHole:MountingHole_3.2mm_M3_ISO14580" H 1750 10550 50  0001 C CNN
+F 3 "~" H 1750 10550 50  0001 C CNN
+	1    1750 10550
+	1    0    0    -1  
+$EndComp
+$Comp
+L power:-15V #PWR020
+U 1 1 5FD1ED25
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+F 0 "#PWR020" H 1450 7000 50  0001 C CNN
+F 1 "-15V" H 1465 7073 50  0000 C CNN
+F 2 "" H 1450 6900 50  0001 C CNN
+F 3 "" H 1450 6900 50  0001 C CNN
+	1    1450 6900
+	1    0    0    -1  
+$EndComp
+$Comp
+L Device:C C7
+U 1 1 5FD2083C
+P 1450 7250
+AR Path="/5FD2083C" Ref="C7"  Part="1" 
+AR Path="/5FA7BAE6/5FD2083C" Ref="C?"  Part="1" 
+F 0 "C7" H 1335 7204 50  0000 R CNN
+F 1 "100nF" H 1335 7295 50  0000 R CNN
+F 2 "Capacitor_THT:C_Disc_D5.0mm_W2.5mm_P5.00mm" H 1488 7100 50  0001 C CNN
+F 3 "~" H 1450 7250 50  0001 C CNN
+	1    1450 7250
+	-1   0    0    1   
+$EndComp
+Wire Wire Line
+	1450 6900 1450 7000
+Wire Wire Line
+	1450 7000 1450 7100
+Connection ~ 1450 7000
+Wire Wire Line
+	1450 7400 1450 7500
+Text Notes 6050 900  0    50   ~ 0
+TODO: Better use 5V?\nrd: 2.3 V (390R @15V)\ngn: 2.4 V (390R @15V)\nye: 2.6 V (390R @15V)
+$Comp
+L power:GNDREF #PWR013
+U 1 1 5FABEB24
+P 1600 1200
+F 0 "#PWR013" H 1600 950 50  0001 C CNN
+F 1 "GNDREF" H 1605 1027 50  0000 C CNN
+F 2 "" H 1600 1200 50  0001 C CNN
+F 3 "" H 1600 1200 50  0001 C CNN
+	1    1600 1200
+	1    0    0    -1  
+$EndComp
+Wire Wire Line
+	1600 1100 1600 1200
+$Comp
 L power:PWR_FLAG #FLG0102
 U 1 1 5FEDB40E
-P 1250 1100
-F 0 "#FLG0102" H 1250 1175 50  0001 C CNN
-F 1 "PWR_FLAG" H 1250 1273 50  0000 C CNN
-F 2 "" H 1250 1100 50  0001 C CNN
-F 3 "~" H 1250 1100 50  0001 C CNN
-	1    1250 1100
+P 1350 1100
+F 0 "#FLG0102" H 1350 1175 50  0001 C CNN
+F 1 "PWR_FLAG" H 1350 1273 50  0000 C CNN
+F 2 "" H 1350 1100 50  0001 C CNN
+F 3 "~" H 1350 1100 50  0001 C CNN
+	1    1350 1100
 	1    0    0    1   
 $EndComp
-Connection ~ 1250 1100
+Connection ~ 1350 1100
 Wire Wire Line
-	1250 1100 1500 1100
+	1350 1100 1600 1100
+Wire Wire Line
+	1950 900  2200 900 
+Connection ~ 1950 900 
+$Comp
+L power:PWR_FLAG #FLG0101
+U 1 1 5FECA14D
+P 1950 900
+F 0 "#FLG0101" H 1950 975 50  0001 C CNN
+F 1 "PWR_FLAG" H 1950 1073 50  0000 C CNN
+F 2 "" H 1950 900 50  0001 C CNN
+F 3 "~" H 1950 900 50  0001 C CNN
+	1    1950 900 
+	1    0    0    -1  
+$EndComp
+Wire Wire Line
+	2200 900  2200 800 
+$Comp
+L power:+15V #PWR012
+U 1 1 5FABF9E5
+P 2200 800
+F 0 "#PWR012" H 2200 650 50  0001 C CNN
+F 1 "+15V" H 2215 973 50  0000 C CNN
+F 2 "" H 2200 800 50  0001 C CNN
+F 3 "" H 2200 800 50  0001 C CNN
+	1    2200 800 
+	1    0    0    -1  
+$EndComp
+$Comp
+L power:PWR_FLAG #FLG01
+U 1 1 5FCE914A
+P 1950 1000
+F 0 "#FLG01" H 1950 1075 50  0001 C CNN
+F 1 "PWR_FLAG" H 1950 1173 50  0000 C CNN
+F 2 "" H 1950 1000 50  0001 C CNN
+F 3 "~" H 1950 1000 50  0001 C CNN
+	1    1950 1000
+	1    0    0    1   
+$EndComp
+$Comp
+L power:-15V #PWR019
+U 1 1 5FCF2E71
+P 2200 1150
+F 0 "#PWR019" H 2200 1250 50  0001 C CNN
+F 1 "-15V" H 2215 1323 50  0000 C CNN
+F 2 "" H 2200 1150 50  0001 C CNN
+F 3 "" H 2200 1150 50  0001 C CNN
+	1    2200 1150
+	-1   0    0    1   
+$EndComp
+Wire Wire Line
+	2200 1150 2200 1000
+Wire Wire Line
+	2200 1000 1950 1000
+Connection ~ 1950 1000
+Text GLabel 1200 800  2    50   Output ~ 0
+Line_Input
+Wire Wire Line
+	1000 800  1200 800 
+Wire Wire Line
+	1000 1100 1350 1100
+Wire Wire Line
+	1000 1000 1950 1000
+Wire Wire Line
+	1000 900  1950 900 
 $EndSCHEMATC
--- a/vu_meter.pdf
+++ b/vu_meter.pdf