Features:

  • Using IO trigger for at least 10us high level signal
  • The module automatically sends eight 40 kHz and detect whether there is a pulse signal back
  • If the signal back, through high level ,time of high output IO duration is the time from sending ultrasonic to returning. Test distance = (high level time velocity of sound (340M/S) /2
  • Power supply :5V DC, quiescent current : <2mA,effectualangle: <15 ranging distance : 2cm~500 cm resolution : 0.3 cm
  • Package Content: 10pcs HC-SR04
Very good inexpensive sensor

This model of the HC-SR04 has performed well for an inexpensive sensor. There are a number of these HC-SR04's on the market, with at least 2 different chip layouts (I don't know how else to identify them). The "other layout" model has pretty consistently locked up or burned out when triggered too frequently. A class of 20 beginner students was unable to damage a single one of these. On the side of don't expect too much from an inexpensive sensor, they do have a limited range and work best against hard flat surfaces. Small and/or soft objects produce jumpy data. The data consistency can be improved by using a median filter (if you know how to find or write one). I plan to purchase 20 more for my next class.

Best deal you'll find

Never though I'd say this about a mass-manufactured Chinese product with a per-unit price 4% of name brands, but this is a purchase you will not regret. I normally wouldn't even consider buying this due to the "amazon effect": seeing a definitely-too-good-to-be-true deal, then buying it in a moment of weakness and ending up wasting more money in the end because it works like crap and you have to by another one. This is NOT the case with this product!! All units gave results comparable to name brands (like Ping) -- with a minimum distance less than an inch, and good consistency and accuracy. Arrived far before the estimated shipping date -- only took 6 days. My only concern is that two units had slight dents in the "eyes", but it did not seem to affect their performance at all. Even if half of them were duds I would still be impressed by the price and quality of this product. Can't recommend them enough if your doing a robotics project (like me), and need tons of distance sensors without emptying your wallet.

Sensor

quick shipping, as advertised . good value .. works well

It showed up earlier than expected by about 10 days ...

It showed up earlier than expected by about 10 days. Tested all 10, all of them worked and I'd say they are all within about +/- 1cm of each other on accuracy, maybe be closer to 0.5 cm, just did a quick test to verify they all worked and checked the distance they were reporting. $13 for 10 vs $30 for one from the local store, can't beat this price!

A vey good value

This 10 pack of HC-SR04 ultrasonic distance sensors is a great value. I received them way, way ahead of schedule and tested all 10 the day they arrived. All worked perfectly. It's good to have spares of this really this useful sensor for your microcontroller and robot projects.

Always need more ultrasonic detectors

Came very fast and worked as advertised

Received them but haven't tested any yet. It was ...

Received them but haven't tested any yet. It was really neat having them all in twos connected by the pcb and splitting them myself. Update when I get em up and running.

as expected

arrived on time, all 10 pieces, very well packaged. no complaints

They work great, what else can you say?

They work like they are supposed to. Nice price. Definitely recommend.

Full Reviews