How to remove the transmitter from ultrasonic hc-sr04 sensor

Other Hardware Sensors
1

Hi
Does someone ever removed the transmitter from this sensor :

http://www.ebay.com/itm/1pcs-Ultrasonic-Module-HC-SR04-Distance-Measuring-Transducer-Sensor-for-Arduino-/261009210866?pt=LH_DefaultDomain_0&hash=item3cc55c7df2

i want to use it only as a receiver ... so everything should keep working as is but without the "speaker"
Thanks
Alex

2

From what I remember of the circuit, I don't see a problem with just de-soldering the TX transducer.
You'll still have to give it a normal trigger sequence to get it to measure.

3

Thanks for the fast reply.
So if i have a good working code right now for distance measure,
and i will disable the speaker from the sensor it will work fine if i will send signal from another ultra sonic speaker ?

4

As long as it is another 40kHz unit, I don't see any problems.

5

Hi, Alex & Awol!
A related question, please.
I am trying to read the signal sent from the transmitter of a module-A (HC-SR04) with the receiver of a module-B (also a HC-SR04).
I do want to keep both modules A and B complete (no desoldering).
In fact what I want is to read signals sent from module-A in module-B, and signals sent from module-B in A, while maintaining the stand-alone ability of each module.
The reason is that this "cross-breeding" should increase the measurement accuracy (at the expense of just few lines of code), and maybe could extend the exploring area to some otherwise blind (or blurry) spots.
So far I am not able to detect the pulses sent from module-A with module-B; it seems to me that the receiver needs the activation done by the emitter sending the ping, on the same module: any idea?

6

it seems to me that the receiver needs the activation done by the emitter sending the ping, on the same module: any idea?

Yes, that's what I would expect too.
What's the problem?

7

The reason is that this "cross-breeding" should increase the measurement accuracy

What is your theory on why this might work?

8

Has anyone been able to do something like this, where one Ultrasonic sensor unit triggers another to return a signal?

Usual echolocation requires a decent reflected signal echo. Active response should work over a much longer distance.

I'd like to publish something like this on the ArduinoInfo.Info WIKI if there is a working example..

9

If "cross-reading" is possible, then the echo location has two additional readings (eliptical) to the ordinary two (circular).
I would expect that 4 readings will increase the accuracy of the measurement at little additional computational cost.

10

Those boards return only the first echo they see, so how will you get the additional readings?

11

At least one of the Devantech units returns multiple echo timings.

12

The cheap Chinese HC-SR04 linked in the OP's first post do not return multiple echos. Here is an interesting and rather complete reverse engineering project on those boards: http://uglyduck.ath.cx/ep/archive/2014/01/Making_a_better_HC_SR04_Echo_Locator.html

@terryking: you may be interested in this cave exploration project that uses multiple remotely triggered, DIY ultrasonic/radio modules to map distances: http://www.interestingto.me.uk/Open%20Source/adventures-ultsasonics

13

Dear Rigonz,

I'm also trying to get one module to send en the other to receive and the other way around.
I'm using a SRF08 and SRF05 at the moment.

Do you have any tips for me?
Did you figuere out a way to detach the sender from module B while still receiving?

Thanks