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From: John R Walliker <jrwalliker@gmail.com>
Newsgroups: sci.electronics.design
Subject: Re: acoustic imager
Date: Wed, 16 Apr 2025 20:04:40 +0100
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On 16/04/2025 17:39, legg wrote:
> On Wed, 16 Apr 2025 07:41:06 -0700, john larkin <jl@glen--canyon.com>
> wrote:
> 
>> On Wed, 16 Apr 2025 09:01:00 +0100, Cursitor Doom <cd@notformail.com>
>> wrote:
>>
>>> On Tue, 15 Apr 2025 15:04:15 -0700, john larkin <jl@glen--canyon.com>
>>> wrote:
>>>
>>>>
>>>> https://www.google.com/aclk?sa=L&ai=DChsSEwjTjaDVg9uMAxW3Hq0GHVmKOlYYACICCAEQARoCcHY&co=1&cce=2&sig=AOD64_3aGs74magNuXwdRGFo7oP8zK-LMQ&ctype=5&q=&adurl=
>>>
>>>
>>> For 42,000 dollars? There's a product there you could develop, John.
>>
>> Seems like it needs maybe a dozen electret mikes, one mux'd ADC, an
>> FPGA, and some code.
>>
>> I'd expect to see a Chinese version on Temu soon.
> 
> Imaging suggests 'bounce', recording requires directivity,filtering
> reflections and long-term (?|)comparison. Back-ground vs spot?
> 
> Measure what?
> 
> RL

It looks as if it is intended for imaging corona discharge.
It probably uses silicon mems microphones.  They tend to have a
poorly damped ultrasonic resonance at around 30kHz which many
fail to show on the data sheets.  This would make them well
suited to ultrasonic reception.
John