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Thread: Rs 170 Ultrasonics transducer pairs

  1. #1

    Default Rs 170 Ultrasonics transducer pairs

    I was just going through docel's post and saw that these sensors are tuned around 56Khz ?

    I think the best way to find out the tuned freq is to find out the maximum/resonating fre of the sensors... but I need a good drive circuit to pulse the sensors with (they are very sensetive and fragile to misusage)

    Anyone got such a circuit ? If not, just an idea to what the circuit should do will do just as well..

    Anyone actually used these Rs 170 Ultrasonics transducer pairs in a project ?

    I am thinking of making a clone of the Devantech SRF04 using these transducers.. anyone tried this before ?

    What do you think ?

  2. #2
    Super Moderator T-1000 docel's Avatar
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    Not ALL of them. What albits and I agreed upon was that these low cost Transducers may respond to other than 40Khz, between them.
    I have also mentioned the possible reasons for this:
    http://roboticsindia.com/modules.php...929&highlight=

    Generally , it is always better to tune the Transmitter Freq to the best response from the 'matched' Receiver.

    Making the SRF04 is not too difficult, seeing that the entire Sch, Layout, Software and history from SRF01...SRF04 is openly published. It is still Copyright, though!
    docel
    ^Anything is possible..
    after YOU prove it!!

    http://bangalorerobotics.tripod.com

  3. #3

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    Yup... I actually wanted to know how to match the transducers..

    Docel, can you tell me what brand these sensors are ? Who makes them ?

    When I called up Railton, they quoted Rs 350 for 40Khz Ultrasonics Tranducers.. are these the same sensors we are talking about ?

    I spoke to R.S just the other day and they told me Murata and Senix brand are available. But I would have to submit a quote request to get their pricing... it's not in their catalog.

    @docel... have you used these sensors yourself ?

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    Super Moderator T-1000 docel's Avatar
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    Hi Vsmguy!
    1. These are from Nippon Ceramics and work quite well.
    The only problem is that they are not matched pairs. They have a slight variation as far as TX and RX response is concerned, between 39.5 to 41Khz. The Murata were off by +/- 300Hz too. This is not a problem unless you want to use it in frequency specific or Phase sensitive applications. Amplitude measurement ( Distance ) is quite ok, if some kind of precalibration is done with the specific transducer pair.
    2. They cannot be replaced without recalibration. This is definitely not a problem.
    3. Railton doesnt sell these anymore. What he has are old sensors lying around in his godown ( and were sold before at that price).

    4. I have used more than 300 hundred of these "Rs.170" transducers. There with some problems with centre freq, Amplitude, distortion, ringing etc., These were due to dust, foriegn body inside, loose pins, bent front grill etc., ( some 14 pairs, still in my junk box ...out of 300!)
    All my transducers are from Om Electronics. I have spoken to Suraj & he will sell it for 125/- a pair, if you say docel/ ROBOTICSINDIA!! He will also courier 1pair minimum order to anywhere. See wiki Banglore.
    docel
    ^Anything is possible..
    after YOU prove it!!

    http://bangalorerobotics.tripod.com

  5. #5
    Senior Member Cyborg
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    he will sell it for 125/- a pair, if you say ROBOTICSINDIA!! He will also courier 1pair minimum order to anywhere. See wiki.

    wow... grt Sir it will be best option for all of us, please also do something for avr microcontrollers also

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    Super Moderator T-1000 docel's Avatar
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    Shashak!
    Bangalore has always been the Cheapest in terms of Components cost (In small/ single Quantities). Let me know your costs else where and I'll proove this contention!
    docel
    ^Anything is possible..
    after YOU prove it!!

    http://bangalorerobotics.tripod.com

  7. #7

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    Docel, can you send me a good drive circuit for the transducers.

    I also wanna ask you :

    1. Can I double up the transmitter as a reciever - i.e, multiplex their use... so I can make a ranging sensor using only one transducer... will that be possible ?

    2. What is the main difference between the transmitter and reciever ?

    3. Do you have datasheets/ technical specifications of the transducers ?

    If possible, I would like to buy the sensors from you rather than from any shop... can that be arranged ?

    Actually my main aim is to make something like :

    http://www.superdroidrobots.com/shop...asp?itemid=706
    http://www.maxbotix.com/uploads/MaxS...-Datasheet.pdf

    It's sooo cool !! Cooler than SFR04 !!

    What do you think...

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    Super Moderator T-1000 docel's Avatar
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    Whoa There VSMguy!!
    1. There are any number of ways that 'distance' can be measured....even without any Microcon. Distance is not measured but sensed as a comparitive value, for a mobile robot and its easy.
    2. Well, there isnt much difference between TX and RX- really :wink:
    I have used both TX and RX in reversed role and they work beautifully.
    3. Another trick: Have you tried using a Telephone Mic/earphone / Piezo Buzzer element??
    You'll be surprised :lol: :!: Thiose things go up to 100 KCs , sometimes.
    The Idea is that the thinner they are the higher the frequency. The more area attached, the lower the freq. (etch with HF...)

    4. Another hack is the Tweeter from your music system......

    Try these out, if you have the time!!!
    docel
    ^Anything is possible..
    after YOU prove it!!

    http://bangalorerobotics.tripod.com

  9. #9

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    Quote Originally Posted by docel
    2. Well, there isnt much difference between TX and RX- really :wink:
    I have used both TX and RX in reversed role and they work beautifully.
    They atleast look the same. In what way are they different ? Are they really different ?

    Why would they need to be different ?
    Quote Originally Posted by docel
    3. Another trick: Have you tried using a Telephone Mic/earphone / Piezo Buzzer element??
    You'll be surprised :lol: :!: Thiose things go up to 100 KCs , sometimes.
    The Idea is that the thinner they are the higher the frequency. The more area attached, the lower the freq. (etch with HF...)
    Pardon me, as this is my intution speaking, but will not attenuation be a BIG problem in this case - that's the reason why we are using Ultrasonics tuned transducers - right ? Reduces ambient sound interference to...

    @Docel : Can you give me circuit / driver to test the transducers beofre I buy them ?

    I would prefer getting the transducers from you rather than a 3rd patry shop ... will that be possible ?

    Any chance you may part with the defective ones you have ? Maybe we should chat offline ?

    Let me know!

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    Super Moderator T-1000 docel's Avatar
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    Well, attenuation is a problem- actually , lets call it as 'low response': but respond they will!!
    1.The difference is supposed to be in the "cut" or orientation of the crystal.

    2. There is no reduction in ambient sound. The spurious response , sometimed is more than the resonant amplitude!! This is negated by active filtering/ techniques.

    3. Sorry! These transducers are a part of my Demo Kit (Cant go around for dead sensors :lol: :lol: ) Also , I'm not through with the R&D of their behaviour
    4. I cannot sell you these things, as i dont bulk source them yet, nor can i justify selling them at a higher price than i have quoted 8O 8O .
    But , maybe, i can test them for performance before they are shipped to you.....
    docel
    ^Anything is possible..
    after YOU prove it!!

    http://bangalorerobotics.tripod.com

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