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Revert "Change emphasis time constant to 750µS"

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Jonathan Naylor 2020-04-30 11:23:19 +01:00 • committed by GitHub
parent be0690e587
commit cc785e3225
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2 changed files with 11 additions and 14 deletions
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21
Tools/emphasis.txt
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@ -9,24 +9,21 @@ clear all;
clc;
fs = 24000;
timeConstant = 0.00075; %750µS
samplingtime = 1/fs;
% analog prototype
A2 = [1];
B2 = [timeConstant 1];
B2 = [0.000075 1];
% Pre
%Ds = tf(B2, A2);
Ds = tf(B2, A2);
% De
Ds = tf(A2, B2);
% Ds = tf(A2, B2);
Ds = Ds/dcgain(Ds);
% MZT
T1 = timeConstant;
T1 = 0.000075; % 75us
z1 = -exp(-1.0/(fs*T1));
p1 = 1+z1;
@ -40,12 +37,12 @@ b2 = 0;
% swap between a1, b1 to select pre- or de-emphasis
% Pre
%Bmzt = [b0 a1 b2]
%Amzt = [a0 b1 a2]
# Pre
Bmzt = [b0 a1 b2]
Amzt = [a0 b1 a2]
% De
Bmzt = [b0 b1 b2]
Amzt = [a0 a1 a2]
% Bmzt = [b0 b1 b2]
% Amzt = [a0 a1 a2]
DzMZT = tf(Amzt, Bmzt, samplingtime);
DzMZT = DzMZT/dcgain(DzMZT);