High-Tech Spy Stethoscope!





Introduction: High-Tech Spy Stethoscope!

Hear through walls AND record what you hear with this High-Tech Electronic Spy Stethoscope for under $25! See the Test Results in the Video!

Step 1: What You Need...

1) Stethoscope. I picked mine up at a local drug store (Walgreens) for $10
2) A pair of Stereo Multimedia Microphones. Chosen because of the low cost and decent specs. $12 on Ebay.
3) 3.5mm (mini) Stereo Y-Adapter. ($0. I had one laying around but they are probably a couple of bucks)

Step 2: Disassembly...

I disassembled the multimedia microhones using an X-Acto knife and assorted tools. I cut it down the middle to get to the cabling and also popped the top off the header to get the mics out. I ended up with 2 mics and 3.5mm connectors.

Step 3: Stethoscope Disassembly...

Remove the earpieces from the Steth. Then I drilled out the earpieces to the diameter of the mic housings. I used a Dremel with a grinding attachment to fine tune it.

Step 4: Reassembly...

I used a small dot of hot glue and inserted the microphones into the earpieces and then reassembled the earpieces on the Stethoscope.

Step 5: Final Results!

After plugging the two 3.5mm connectors into the Y-Adapter and then plugging the single stereo connector into my MP3 player, I was ready to test it out! Check out the video! Hope you like it and give it a try!



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    How Is the Audio of this? can you hear people well? how well?

    If you're looking for the smallest GPS tracker with audio and video recording with MMS message, here you go:


    All you need to do is hide it somewhere in a room, under a table, in a closet or a handbag, it's so small nobody will even notice it.

    i cant find the mics anywhere


    I found this YouTube video interesting:


    .One more thing, all the other schematics I have looked at using LM386 have pins #2 & #3 reversed from the schematic published here.

    This might not cause any problems, since nobody else has commented about this discrepancy.

    You are a genius!!
    I am a physician blood pressure specialist
    I need to measure BP sometimes 30 times a day
    This device is fantastic because I do not have to plug the dirty stethoscope ear plugs into my ears !!

    How could these microphones be connected to an amplifier/speaker instead of an mp3 player?

    If you want to spend $400 you can get a stethoscope for the hearing impaired that has an amplifier on it. Take the diaphragm and secure it to the wall with a bracket and then there will be headphones Not as fun as analog scanners before phones went digital but a nice party favor.

    Does the adapter turn the headphone port on an MP3 player into a microphone?

    no just makes two ports instead of one. your mp3 has to have a mic port & recording capabilities