What (if anything) would you recommend to monitor frequencies above 25 KHz - say up as high as 80 KHz?

Allow me to guess...a new DLI product?

Alan,

Ultrasound sensors are available at low cost for that frequency range and higher. Most of the contact sensors are actually airborne sound sensors mounted "on a stick".

Walt
w_f_strong [at] msn [dot] com

Wrong board?

Come on Darth, think outside the box!!

Walt

Thanks Walt! I'm not sure what I did to deserve 2 sarcastic answers to a very straightforward question? Oh well... here's another related question - anyone know anything about MEMs sensor capabilities in these frequencies?

Alan,

I would guess one of the reply's may have been anticipating a sales pitch [based on your home location-same as DLI!]

Regardless, Ultrasonic monitoring could be one approach or perhaps some sort of demodulation-based monitoring such as Peak Vue or Spike Energy. Most depends entirely on what you are monitoring and what you are looking for and what you may or may not have readily available in the form of hardware?

I think a little related information from you in this respect, i.e.- "What exactly are you trying to acheive?", might garner a few more valid answers.

Alan,

Forgive me if you thought my reply was ‘sarcastic’ in nature however, and perhaps it is just my interpretation of some of your replies to this forum, but I do believe you ‘plug’ DLI products whenever the situation presents itself.

And I don’t think that is necessarily bad. One should be proud and have pride in the company for which they work and DLI is solid. Furthermore, you do and have made significant contributions to this board, as I see it, both in product insight and general information you have provided. In my experience, most design engineers of condition monitoring products haven’t a clue what the ‘field’ is, let alone understand equipment found there. In that respect I do think you are different, based upon your replies here.

Please accept my apologies.

Gary Forsythe

Alan,
When looking at MEMS, most I find is the volume lo freq. devices for airbags and automotive. There has been some versions that almost would be possible for normal vibration use but for hi freq. I have not found anything suitable MEMS so far. Olov