diff --git a/grc_tests/bpsk31_tedvar.m b/grc_tests/bpsk31_tedvar.m
index f05c84a..af43a8f 100755
--- a/grc_tests/bpsk31_tedvar.m
+++ b/grc_tests/bpsk31_tedvar.m
@@ -5,7 +5,26 @@
 %pkg install -forge parallel
 pkg load parallel
 
-system('cat /dev/urandom | csdr pack_bits_8to1_u8_u8 | csdr psk_modulator_u8_c 2 | csdr gain_ff 0.25 | csdr psk31_interpolate_sine_cc 256 | csdr add_n_zero_samples_at_beginning_f 170 | dd iflag=fullblock bs=8M count=1 of=/tmp/psk31-raw-data');
+function y=inarg(x)
+    for i=1:length(argv())
+        if strcmp(argv(){i},x)
+            y=1;
+            return
+        end
+    end
+    y=0;
+end
+
+if !inarg('--nogen')
+    fwrite(stdout, "===========================================\nGenerating baseband signal from random data\n===========================================\n");
+    system('cat /dev/urandom | csdr pack_bits_8to1_u8_u8 | csdr psk_modulator_u8_c 2 | csdr gain_ff 0.25 | csdr psk31_interpolate_sine_cc 256 | csdr add_n_zero_samples_at_beginning_f 170 | pv -ps 2g | dd iflag=fullblock bs=128M count=16 of=/tmp/psk31-raw-data');
+    fwrite(stdout, "===========================================\nGenerating Gaussian white noise for agwn_cc\n===========================================\n");
+    system('csdr gaussian_noise_c | pv -ps 256m | dd of=/tmp/psk31-gaussian-noise iflag=fullblock bs=256M count=1');
+end
+if inarg('--onlygen') 
+    exit(0)
+end
+fwrite(stdout, "===========================================\nCalculating variance graph data            \n===========================================\n");
 
 function output=shrun(cmd, type, minsize)
     SIGTERM=15;
@@ -30,10 +49,10 @@ end
 
 function variance=run_var(snr, which_ted)
     disp('ran a command')
-    out_vect=shrun(sprintf('cat /tmp/psk31-raw-data | csdr awgn_cc %d --snrshow-no| csdr timing_recovery_cc %s 256 --add_q --output_indexes | CSDR_FIXED_BUFSIZE=2048 csdr normalized_timing_variance_u32_f 256 85', snr, which_ted), 'float32', 2);
+    out_vect=shrun(sprintf('cat /tmp/psk31-raw-data | csdr awgn_cc %d --awgnfile /tmp/psk31-gaussian-noise | csdr timing_recovery_cc %s 256 --add_q --output_indexes | CSDR_FIXED_BUFSIZE=1048576 csdr normalized_timing_variance_u32_f 256 85', snr, which_ted), 'float32', 1);
     disp('run_var output:');
     out_vect'
-    variance=out_vect(2);
+    variance=out_vect(1);
 end
 
 function variances=mkvarplot(which_ted, snrs)
@@ -60,7 +79,7 @@ end
 
 snrs=-5:5:30
 %snrs=[10]
-error_values_gardner=mkvarplot('EARLYLATE',snrs);
+error_values_gardner=mkvarplot('GARDNER',snrs);
 %{
 snrs_earlylate=0:256
 error_values_earlylate=mkvarplot('EARLYLATE',snrs_earlylate);
@@ -69,7 +88,6 @@ error_values_earlylate=mkvarplot('EARLYLATE',snrs_earlylate);
 %graphics_toolkit("gnuplot")
 h=figure(1);
 
-
 ebn0=snrs-13.26-10*log10(1/256.)
 %13.56 dB is the difference between the real (measured) SNR and the number input to awgn_cc.
 %This is because agwn_cc assumes a signal with 0dB power at te input, while our BPSK31 baseband signal is of -13.26 dB.
@@ -86,4 +104,6 @@ fmtplot(h)
 pause
 %}
 
-system('rm /tmp/psk31-raw-data');
+if !inarg('--nogen')
+    system('rm /tmp/psk31-raw-data /tmp/psk31-gaussian-noise');
+end