diff --git a/pcb_calculator/attenuators/bridget_tee_formula.h b/pcb_calculator/attenuators/bridget_tee_formula.h
index 95ac299128..94d6382d15 100644
--- a/pcb_calculator/attenuators/bridget_tee_formula.h
+++ b/pcb_calculator/attenuators/bridget_tee_formula.h
@@ -5,7 +5,7 @@ _HKI( "### Bridged Tee Attenuator\n"
"___Zout___ is desired output impedance in Ω
\n"
"___Z0 = Zin = Zout___\n"
"\n"
-"___L = 10a/20___\n"
-"___R1 = Z0 · (L−1)___
\n"
-"___R2 = Z0 / (L−1)___\n"
+"___L = 10a/20___
\n"
+"___R1 = Z0 · (L−1)___
\n"
+"___R2 = Z0 / (L−1)___\n"
"" );
diff --git a/pcb_calculator/attenuators/bridget_tee_formula.md b/pcb_calculator/attenuators/bridget_tee_formula.md
index 4d0df56598..b747b2835b 100644
--- a/pcb_calculator/attenuators/bridget_tee_formula.md
+++ b/pcb_calculator/attenuators/bridget_tee_formula.md
@@ -4,6 +4,6 @@ ___Zin___ is desired input impedance in Ω
___Zout___ is desired output impedance in Ω
___Z0 = Zin = Zout___
-___L = 10a/20___
-___R1 = Z0 · (L−1)___
-___R2 = Z0 / (L−1)___
+___L = 10a/20___
+___R1 = Z0 · (L−1)___
+___R2 = Z0 / (L−1)___
diff --git a/pcb_calculator/attenuators/pi_formula.h b/pcb_calculator/attenuators/pi_formula.h
index 4016a91b22..33c5ffb9cb 100644
--- a/pcb_calculator/attenuators/pi_formula.h
+++ b/pcb_calculator/attenuators/pi_formula.h
@@ -6,7 +6,7 @@ _HKI( "### Pi Attenuator\n"
"\n"
"___L = 10a/20___
\n"
"___A = (L+1) / (L−1)___
\n"
-"___R2 = (L−1) / 2·√(Zin · Zout / L)___
\n"
-"___R1 = 1 / (A/Zin − 1/R2)___
\n"
-"___R3 = 1 / (A/Zout − 1/R2)___\n"
+"___R2 = (L−1) / 2·√(Zin · Zout / L)___
\n"
+"___R1 = 1 / (A/Zin − 1/R2)___
\n"
+"___R3 = 1 / (A/Zout − 1/R2)___\n"
"" );
diff --git a/pcb_calculator/attenuators/pi_formula.md b/pcb_calculator/attenuators/pi_formula.md
index f443a06c23..68785d254b 100644
--- a/pcb_calculator/attenuators/pi_formula.md
+++ b/pcb_calculator/attenuators/pi_formula.md
@@ -5,6 +5,6 @@ ___Zout___ is desired output impedance in Ω
___L = 10a/20___
___A = (L+1) / (L−1)___
-___R2 = (L−1) / 2·√(Zin · Zout / L)___
-___R1 = 1 / (A/Zin − 1/R2)___
-___R3 = 1 / (A/Zout − 1/R2)___
+___R2 = (L−1) / 2·√(Zin · Zout / L)___
+___R1 = 1 / (A/Zin − 1/R2)___
+___R3 = 1 / (A/Zout − 1/R2)___
diff --git a/pcb_calculator/attenuators/splitter_formula.h b/pcb_calculator/attenuators/splitter_formula.h
index 0ba58290c1..f9667dad07 100644
--- a/pcb_calculator/attenuators/splitter_formula.h
+++ b/pcb_calculator/attenuators/splitter_formula.h
@@ -5,5 +5,5 @@ _HKI( "### Split Attenuator\n"
"___Zout___ is desired output impedance in Ω \n"
"___Z0 = Zin = Zout___\n"
"\n"
-"___R1 = R2 = R3 = Z0/3___\n"
+"___R1 = R2 = R3 = Z0/3___\n"
"" );
diff --git a/pcb_calculator/attenuators/splitter_formula.md b/pcb_calculator/attenuators/splitter_formula.md
index 4f782e88e0..1833bef278 100644
--- a/pcb_calculator/attenuators/splitter_formula.md
+++ b/pcb_calculator/attenuators/splitter_formula.md
@@ -4,4 +4,4 @@ ___Zin___ is desired input impedance in Ω
___Zout___ is desired output impedance in Ω
___Z0 = Zin = Zout___
-___R1 = R2 = R3 = Z0/3___
+___R1 = R2 = R3 = Z0/3___
diff --git a/pcb_calculator/attenuators/tee_formula.h b/pcb_calculator/attenuators/tee_formula.h
index 5e54c7ecab..49b2244e82 100644
--- a/pcb_calculator/attenuators/tee_formula.h
+++ b/pcb_calculator/attenuators/tee_formula.h
@@ -5,8 +5,8 @@ _HKI( "### Tee Attenuator\n"
"___Zout___ is desired output impedance in Ω
\n"
"\n"
"___L = 10a/20___
\n"
-"___A = (L+1) / (L−1)___
\n"
-"___R2 = 2·√(L · Zin · Zout) / (L−1)___
\n"
-"___R1 = Zin · A − R2___
\n"
-"___R3 = Zout · A − R2___\n"
+"___A = (L+1) / (L−1)___
\n"
+"___R2 = 2·√(L · Zin · Zout) / (L−1)___
\n"
+"___R1 = Zin · A − R2___
\n"
+"___R3 = Zout · A − R2___\n"
"" );
diff --git a/pcb_calculator/attenuators/tee_formula.md b/pcb_calculator/attenuators/tee_formula.md
index d40846f42a..e341e31cbf 100644
--- a/pcb_calculator/attenuators/tee_formula.md
+++ b/pcb_calculator/attenuators/tee_formula.md
@@ -4,7 +4,7 @@ ___Zin___ is desired input impedance in Ω
___Zout___ is desired output impedance in Ω
___L = 10a/20___
-___A = (L+1) / (L−1)___
-___R2 = 2·√(L · Zin · Zout) / (L−1)___
-___R1 = Zin · A − R2___
-___R3 = Zout · A − R2___
+___A = (L+1) / (L−1)___
+___R2 = 2·√(L · Zin · Zout) / (L−1)___
+___R1 = Zin · A − R2___
+___R3 = Zout · A − R2___
diff --git a/pcb_calculator/calculator_panels/panel_attenuators_base.cpp b/pcb_calculator/calculator_panels/panel_attenuators_base.cpp
index 9e6b5d8045..745b4017b0 100644
--- a/pcb_calculator/calculator_panels/panel_attenuators_base.cpp
+++ b/pcb_calculator/calculator_panels/panel_attenuators_base.cpp
@@ -18,7 +18,7 @@ PANEL_ATTENUATORS_BASE::PANEL_ATTENUATORS_BASE( wxWindow* parent, wxWindowID id,
bLeftSizerAtt = new wxBoxSizer( wxVERTICAL );
bLeftSizerAtt->SetMinSize( wxSize( 260,-1 ) );
- wxString m_AttenuatorsSelectionChoices[] = { _("PI"), _("Tee"), _("Bridged tee"), _("Resistive splitter") };
+ wxString m_AttenuatorsSelectionChoices[] = { _("Pi"), _("Tee"), _("Bridged tee"), _("Resistive splitter") };
int m_AttenuatorsSelectionNChoices = sizeof( m_AttenuatorsSelectionChoices ) / sizeof( wxString );
m_AttenuatorsSelection = new wxRadioBox( this, wxID_ANY, _("Attenuators"), wxDefaultPosition, wxDefaultSize, m_AttenuatorsSelectionNChoices, m_AttenuatorsSelectionChoices, 1, wxRA_SPECIFY_COLS );
m_AttenuatorsSelection->SetSelection( 2 );
diff --git a/pcb_calculator/calculator_panels/panel_attenuators_base.fbp b/pcb_calculator/calculator_panels/panel_attenuators_base.fbp
index e010f71a00..18185c7f8c 100644
--- a/pcb_calculator/calculator_panels/panel_attenuators_base.fbp
+++ b/pcb_calculator/calculator_panels/panel_attenuators_base.fbp
@@ -84,7 +84,7 @@
1
0
- "PI" "Tee" "Bridged tee" "Resistive splitter"
+ "Pi" "Tee" "Bridged tee" "Resistive splitter"
1
1