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diff --git a/notes/audio/30hz_loop.mp3 b/notes/audio/30hz_loop.mp3
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diff --git a/notes/images/laptop-cpu.jpg b/notes/images/laptop-cpu.jpg
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diff --git a/notes/images/raspberry-pi-cpu.jpg b/notes/images/raspberry-pi-cpu.jpg
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diff --git a/notes/time_report.md b/notes/time_report.md
index d31ce27..6a5d539 100644
--- a/notes/time_report.md
+++ b/notes/time_report.md
@@ -17,3 +17,11 @@
   * No change measurable in magnetmeter even if I can see the coil vibrate
   * I assume the change in the magnetic field is too small to be measured
 * Finish project plan
+
+# 2022-09-26
+* Test Magnetic Field of Laptop CPU
+  * I can clearly see the spikes
+* Another try on the Raspberry Pi
+  * Still nothing accurate
+* Research other solutions
+  * https://www.cs.sjtu.edu.cn/~yichao/pmwiki/assets/publications/mobicom17_pan.pdf
diff --git a/src/stress-cpu.sh b/src/stress-cpu.sh
new file mode 100755
index 0000000..d39b587
--- /dev/null
+++ b/src/stress-cpu.sh
@@ -0,0 +1,7 @@
+#!/usr/bin/env sh
+
+while true
+do
+    stress --cpu 8 --timeout 2
+    sleep 2
+done