diff --git a/firmware/scripts/sstv_test.py b/firmware/scripts/sstv_test.py
new file mode 100644
index 0000000..dedf0dd
--- /dev/null
+++ b/firmware/scripts/sstv_test.py
@@ -0,0 +1,120 @@
+#/usr/bin/env python3
+import numpy as np
+
+
+from scipy.io import wavfile
+from scipy.misc import imread
+from matplotlib import pyplot as plt
+
+
+WIDTH = 640
+HEIGHT = 496
+
+OUTPUT_RATE = 48000
+
+VIS_START_FREQ = 1900
+VIS_START_DUR = 300
+VIS_PAUSE = 10
+VIS_ONE_FREQ = 1100
+VIS_ZERO_FREQ = 1300
+VIS_BIT_DUR = 30
+# Code 97 + even parity, lsb first
+VIS_BITS = [True, False, False, False, False, True, True, True]
+
+SYNC_FREQ = 1200
+SYNC_DUR = 20
+
+PORCH_DUR = 2.080
+
+PIXEL_DUR = 0.382
+
+COLOR_LOW_FREQ = 1500
+COLOR_HIGH_FREG = 2300
+
+phase_acc = 0
+
+
+def sine_gen(freq):
+    global phase_acc
+    phase_inc = (2 * np.pi / OUTPUT_RATE) * freq
+    phase_acc += phase_inc
+    if phase_acc > 2 * np.pi:
+        phase_acc = phase_acc - 2 * np.pi
+
+    return np.sin(phase_acc)
+
+
+samples_left = 0
+def make_tone(freq, duration, data):
+    global samples_left
+    samples = duration / 1000 * OUTPUT_RATE + samples_left
+    sample_count = int(samples)
+    samples_left = samples - sample_count
+
+    for i in range(0, sample_count):
+        data += [sine_gen(freq)]
+
+
+
+
+def make_vis(samples):
+    make_tone(VIS_START_FREQ, VIS_START_DUR, samples)
+    make_tone(SYNC_FREQ, VIS_PAUSE, samples)
+    make_tone(VIS_START_FREQ, VIS_START_DUR, samples)
+
+    make_tone(SYNC_FREQ, VIS_BIT_DUR, samples)
+    for bit in VIS_BITS:
+        if bit:
+            make_tone(VIS_ONE_FREQ, VIS_BIT_DUR, samples)
+        else:
+            make_tone(VIS_ZERO_FREQ, VIS_BIT_DUR, samples)
+
+    make_tone(SYNC_FREQ, VIS_BIT_DUR, samples)
+
+
+def main():
+
+    image = imread('testcard.png', mode='YCbCr')
+
+    samples = []
+
+    make_vis(samples)
+
+    for y in range(0, int(HEIGHT/2)):
+        make_tone(SYNC_FREQ, SYNC_DUR, samples)
+        make_tone(COLOR_LOW_FREQ, PORCH_DUR, samples)
+
+        for x in range(0, WIDTH):
+            lum = image[y*2, x, 0] / 255.0
+            freq = COLOR_LOW_FREQ + lum * (COLOR_HIGH_FREG - COLOR_LOW_FREQ)
+            make_tone(freq, PIXEL_DUR, samples)
+
+        for x in range(0, WIDTH):
+            cr0 = image[y*2, x, 2] / 255.0
+            cr1 = image[y*2 + 1, x, 2] / 255.0
+            cr = (cr0 + cr1) / 2
+            freq = COLOR_LOW_FREQ + cr * (COLOR_HIGH_FREG - COLOR_LOW_FREQ)
+            make_tone(freq, PIXEL_DUR, samples)
+
+        for x in range(0, WIDTH):
+            cb0 = image[y*2, x, 1] / 255.0
+            cb1 = image[y*2 + 1, x, 1] / 255.0
+            cb = (cb0 + cb1) / 2
+            freq = COLOR_LOW_FREQ + cb * (COLOR_HIGH_FREG - COLOR_LOW_FREQ)
+            make_tone(freq, PIXEL_DUR, samples)
+
+        for x in range(0, WIDTH):
+            lum = image[y*2 + 1, x, 0] / 255.0
+            freq = COLOR_LOW_FREQ + lum * (COLOR_HIGH_FREG - COLOR_LOW_FREQ)
+            make_tone(freq, PIXEL_DUR, samples)
+
+
+    samples = np.array(samples)
+
+    samples = samples * 0.75 * 32767
+    samples = np.int16(samples)
+
+    wavfile.write("output.wav", OUTPUT_RATE, samples)
+
+if __name__ == '__main__':
+    main()
diff --git a/firmware/scripts/testcard.png b/firmware/scripts/testcard.png
new file mode 100644
index 0000000..a0cce5a
Binary files /dev/null and b/firmware/scripts/testcard.png differ