Digital Diagnostic Stethoscope

Comments about Cen-Tech Digital Diagnostic Stethoscope:

I was wary about buying a sensitive electronic diagnostic tool from Harbor Freight, but a good set of "ears" can really help with diagnosing bad pulleys, bearings, and pumps, and I wanted something better than an old fashioned mechanical set. These were a really cheap option, especially when they're on sale. Other electronic stethoscopes start out at 4 or 5 times as expensive, so I figured what do I have to lose, I'll try these.

Man, what a surprise. Not only do they work great, but they actually have some benefits that the more expensive sets don't have:

1. Nice, long probes. (Longer than microphone style sets)
2. It has solid steel probes that are extremely sturdy compared to hollow ones or microphones.
3. Solid probes are really easy to fabricate on your own with some standard steel rods and a tap and die set! (90 degree probes, anyone? yes please)
4. You can hear noises from deeper inside the engine easier.
5. Surrounding noises don't interfere as much as with microphones.

And because it's electronic, you get three advantages over a mechanical stethoscope:
1. MUCH greater comfort. No contorted bending over because your stethoscope is connected by a short rubber hose.
2. More sensitive than mechanical diaphragm, and easier to get a good listening point (you don't even HAVE to touch the object with the tip of the probe!)
3. You can replace headphones with whatever headphones you want at any time. Personally I recommend high quality noise cancelling ones.

The only disadvantages I can think of is your probe does have to be touching whatever you're listening to, and you will still have to listen from several places to make sure the noise you're listening to isn't transmitting through the engine from another place, but really you should do that no matter what type of listening device you use, and only takes another minute or two so there's no reason not to.

If you have an expensive microphone-style stethoscope you're probably still going to want to carry these along, and for a part-time mechanic it might be all you need if you want something better than the cheap-o mechanical ones.

They come with a great carrying case too! That's kind of a shocker at this pricing. I love these.