improve coupling at mixer

1 files changed, 66 insertions, 20 deletions

diff --git a/gschem/outputs.sch b/gschem/outputs.sch
index a585aaf..7ee7c37 100644
--- a/gschem/outputs.sch
+++ b/gschem/outputs.sch
@@ -9,13 +9,13 @@ device=none
 T 47600 49700 5 10 1 1 0 7 1
 value=Bass
 }
-C 47000 45500 1 0 0 input-2.sym
+C 46300 45500 1 0 0 input-2.sym
 {
-T 47000 45700 5 10 1 0 0 0 1
+T 46300 45700 5 10 1 0 0 0 1
 net=MELODY:1
-T 47600 46200 5 10 0 0 0 0 1
+T 46900 46200 5 10 0 0 0 0 1
 device=none
-T 47500 45600 5 10 1 1 0 7 1
+T 46800 45600 5 10 1 1 0 7 1
 value=Melody
 }
 C 48900 49500 1 0 0 capacitor-4.sym
@@ -32,22 +32,22 @@ T 48900 49500 5 10 0 1 0 0 1
 footprint=RCY100P
 }
 N 48900 49700 48500 49700 4
-C 48800 45400 1 0 0 capacitor-4.sym
+C 48100 45400 1 0 0 capacitor-4.sym
 {
-T 49000 46500 5 10 0 0 0 0 1
+T 48300 46500 5 10 0 0 0 0 1
 device=POLARIZED_CAPACITOR
-T 49000 45900 5 10 1 1 0 0 1
+T 48300 45900 5 10 1 1 0 0 1
 refdes=C504
-T 49000 46100 5 10 0 0 0 0 1
+T 48300 46100 5 10 0 0 0 0 1
 symversion=0.1
-T 48800 45400 5 10 1 1 0 0 1
+T 48100 45400 5 10 1 1 0 0 1
 value=10u
-T 48800 45400 5 10 0 1 0 0 1
+T 48100 45400 5 10 0 1 0 0 1
 footprint=RCY100P
 }
-N 48800 45600 48400 45600 4
+N 48100 45600 47700 45600 4
 N 49800 49700 53400 49700 4
-N 49700 45600 50100 45600 4
+N 49000 45600 50100 45600 4
 C 51000 45700 1 180 0 resistor-2.sym
 {
 T 50600 45350 5 10 0 0 180 0 1
@@ -75,14 +75,14 @@ footprint=R025
 N 51600 44800 51600 45600 4
 N 51000 45600 51600 45600 4
 N 51000 44800 51600 44800 4
-N 48400 44800 50100 44800 4
-C 47000 44700 1 0 0 input-2.sym
+N 49000 44800 50100 44800 4
+C 46300 44700 1 0 0 input-2.sym
 {
-T 47000 44900 5 10 1 0 0 0 1
+T 46300 44900 5 10 1 0 0 0 1
 net=JACKSWITCH_B:1
-T 47600 45400 5 10 0 0 0 0 1
+T 46900 45400 5 10 0 0 0 0 1
 device=none
-T 47500 44800 5 10 1 1 0 7 1
+T 46800 44800 5 10 1 1 0 7 1
 value=from B Jack switch
 }
 C 54600 44300 1 0 0 capacitor-4.sym
@@ -113,7 +113,7 @@ C 55500 42500 1 0 0 vcc-minus-1.sym
 N 55500 44500 56800 44500 4
 N 55800 44500 55800 44200 4
 N 55800 43300 55800 43100 4
-T 47300 42000 9 10 1 0 0 0 8
+T 45900 39700 9 10 1 0 0 0 9
 When there's no cable connected to output B,
 the blended bass signal lies on JACKSWITCH_B:1.
 The circuit will mix the melody and bass signals
@@ -121,7 +121,8 @@ to one mono signal.
 
 When a cable is connected, i.e. when stereo
 output is requested, there is no signal on
-JACKSWITCH_B:1.
+JACKSWITCH_B:1, so we need R517 to pull down
+the input to a defined potential.
 C 56800 43700 1 0 0 connector2-2.sym
 {
 T 57500 45000 5 10 1 1 0 6 1
@@ -219,7 +220,7 @@ device=RESISTOR
 T 53400 43900 5 10 1 1 0 0 1
 refdes=R507
 T 53400 43700 5 10 1 1 0 0 1
-value=3k3
+value=4k7
 T 53100 44400 5 10 0 1 0 0 1
 footprint=R025
 }
@@ -321,3 +322,48 @@ T 61000 45700 5 10 1 1 0 0 1
 value=1mH
 }
 N 61600 45900 61700 45900 4
+C 49600 44600 1 270 0 resistor-2.sym
+{
+T 49950 44200 5 10 0 0 270 0 1
+device=RESISTOR
+T 49900 44100 5 10 1 1 0 0 1
+refdes=R517
+T 49900 43900 5 10 1 1 0 0 1
+value=100k
+T 49600 44600 5 10 0 1 0 0 1
+footprint=R025
+}
+N 49700 43200 49700 43700 4
+N 49700 44600 49700 44800 4
+T 46100 42500 9 10 1 0 0 0 2
+TODO: orientation of the coupling cap?
+Signal on the right is always on virtual ground, so is higher.
+C 48100 44600 1 0 0 capacitor-4.sym
+{
+T 48300 45700 5 10 0 0 0 0 1
+device=POLARIZED_CAPACITOR
+T 48300 45100 5 10 1 1 0 0 1
+refdes=C505
+T 48300 45300 5 10 0 0 0 0 1
+symversion=0.1
+T 48100 44600 5 10 1 1 0 0 1
+value=10u
+T 48100 44600 5 10 0 1 0 0 1
+footprint=RCY100P
+}
+N 47700 44800 48100 44800 4
+C 49600 42900 1 0 0 gnd-1.sym
+C 49300 45400 1 270 0 resistor-2.sym
+{
+T 49650 45000 5 10 0 0 270 0 1
+device=RESISTOR
+T 49600 45200 5 10 1 1 0 0 1
+refdes=R517
+T 49600 45000 5 10 1 1 0 0 1
+value=100k
+T 49300 45400 5 10 0 1 0 0 1
+footprint=R025
+}
+N 49400 44500 49400 43500 4
+N 49400 43500 49700 43500 4
+N 49400 45400 49400 45600 4