Blood Pressure Monitor, Stethoscope, and Vision Chart
Source: jd.com
Recently, I bought an electronic blood pressure monitor, a stethoscope, and a vision chart, all of which provided interesting learning experiences.
Blood Pressure Monitor
When I tested my blood pressure, I found some variations between my two arms. The first measurement using my left arm showed a systolic pressure of 140mmHg, diastolic pressure of 90mmHg, and a heart rate of 68bpm. The second measurement using my right arm was lower: 120mmHg systolic, 80mmHg diastolic, and 64bpm heart rate.
The experience of using the monitor taught me the importance of technique. Initially, I struggled with properly wrapping the cuff around my arm. I learned that the correct method involves:
- Wrapping the cuff 360 degrees clockwise around your arm.
- Then wrapping an additional 60 degrees counterclockwise.
I also discovered that the iOS health app can be used to record these readings for easy tracking.
Stethoscope
In addition to the blood pressure monitor, I bought a stethoscope to learn how to use it. To my surprise, I found an unexpected application: eavesdropping! By placing the chest piece against a wooden door, I was able to hear surprisingly clear sounds from the other side.
Source: amazon.com
Beyond just eavesdropping, here are some other interesting uses for a stethoscope:
- Listening Through Walls or Doors: Hear faint sounds from the other side.
- Detecting Mechanical Noises: Identify problems in machines, like engines or appliances.
- Detecting Leaks: Listen for air or water leaks in pipes.
- Nature Sounds: Hear subtle sounds in nature, like wind or animal movement.
- Tuning Musical Instruments: Amplify sounds to tune instruments more easily.
- Vibration Detection: Spot structural issues in buildings.
- Scientific Experiments: Amplify subtle sounds for research.
- Creative Sound Recording: Capture unique, distorted sounds.
These tools have practical uses, but it’s important to use them responsibly and respect others’ privacy.
Vision Chart
I bought a vision chart to track my natural vision restoration progress. It only cost me around 10 RMB on JD. I installed it on my bedroom wall as shown below.
An optician at an eyeglasses store taught me how to use it. First, he used a machine to give a brief report on my eyes’ myopia. Then he used several lenses, assembling them like Lego, to combine them. Typically, he would use two myopia lenses and one astigmatism lens to construct glasses for one eye, and vice versa for the other eye.
Then he asked me to stand 5 meters away from the wall. The line I could see clearly indicated my vision level.
When I returned home, I decided I could buy a vision chart and check my eyes myself.
It costs around 30 RMB to test my eyes at the store. Doing it myself isn’t about saving money - it’s about learning.
Interestingly, I’ve now learned a new way to do things.
After a few days, I decided to buy another type of vision chart—a C-shaped vision chart. I installed it in the living room.
