Other Parts Discussed in Thread: PGA460-Q1, PGA460,
Hello,
I am trying to get 3 - 100 Cm distance measurement, with a Beam angle of at least 30 degrees, with a Bi-Static configuration using the transformer method to drive the transducer.
I can get reasonable distance results with 200 kHz Steminc SMATR200H19XDA transducers but the beam angle is too narrow for my Application. I can not find an "off the shelf" 200 Khz transducer with wide beam angle.
when using lower frequency transducers, for example the supplied Murata MA58MF14-7N, I have noticed that the actual ringing time of the transducer as measured with oscilloscope is much shorter than the ringing time as observed on TI PGA460-Q1 software, I measured 300 micro seconds with oscilloscope and 1000 micro seconds with PGA460 software.
even if I disconnect the receiving transducer I still get long ringing time. I wonder why this happens and how can this be solved.
I have read previous posts in E2E forums regarding this issue and applied all the suggestions with no success, including tuning capacitors, damping resistors and lowering the TVG to a minimum at the ringing time.
I also know that theoretically it is possible and there are also cheap sensors like HC-S04 and equivalents with closed top transducers that measure 3 Cm to 2.5 meter with 40 Khz transducers.
So I wonder, is this due to receiving transducer ringing time or some EM coupling somewhere in the system.
I have 3 action courses in mind:
1. to damp the receiving transducer/circuit
2. to use 2 PGA460 one for bursting and one for listening and synchronizing the 2 PGA460 somehow
3. ask for a custom transducer solution from a transducer manufacturer.
Do you have any experience and success with these action courses.
If option 2 is possible what will be the best and fastest method to test it? can I stack two PGA460 on the same MSP-EXP430 Launchpad? how can I synchronize the two PGA460?
Thanks,
Assaf