1 files changed, 0 insertions, 37 deletions
diff --git a/octave/rf_bpf.m b/octave/rf_bpf.m
deleted file mode 100644
index e0a39ba..0000000
--- a/octave/rf_bpf.m
+++ /dev/null
@@ -1,37 +0,0 @@
-% rtlsdr_bpf.m
-%
-% David Rowe 24 August 2018
-%
-% Calculate component values for cascaded HP-LP 2-8 MHz Chebychev filter
-%
-% From "RF Circuit Design", Chris Bowick, Ch 3
-
-1;
-
-function C = find_C(Cn, fc, R)
-  C = Cn/(2*pi*fc*R);
-endfunction
-
-function L = find_L(Ln, fc, R)
-  L = R*Ln/(2*pi*fc);
-endfunction
-
-% 3rd order HP filter, 1dB ripple Cheby, 3MHz cut off, >20dB down at
-% 1MHz to nail strong AM broadcast signals, Table 3-7A. Use a Rs=50,
-% Rl=50, so Rs/Rl = 1.  Note we assume a or phantom load in between
-% cascaded HP-LP sections of 50 ohms.
-
-L1 = find_L(1/2.216, 3E6, 50);
-C1 = find_C(1/1.088, 3E6, 50);
-L2 = find_L(1/2.216, 3E6, 50);
-
-printf("L1: %f uH C1: %f pF L2: %f uH\n", L1*1E6, C1*1E12, L2*1E6);
-
-% 3rd order LPF, 8MHz cut off so >30dB down at 21MHz, which aliases back to 7MHz
-% with Fs=28MHz on RTLSDR (14 MHz Nyquist freq). Rs=50, Rl=50, Rs/Rl = 1
-
-C2 = find_C(2.216, 9E6, 50);
-L3 = find_L(1.088, 9E6, 50);
-C3 = find_C(2.216, 9E6, 50);
-
-printf("C2: %f pF L3: %f uH C3: %f pF\n", C2*1E12, L3*1E6, C3*1E12);