condition monitoring

video and audio clips

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leak detection

find airleaks fast video

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before and after greasing

Good and Bad bearing conditions

 
One of the reasons for the phenomenal success of the MHC range is the clarity of the detected signals (a direct consequence of the unique sensor design and signal processing circuitry).To illustrate this we present you with some audio signals taken from an MHC's headphone output (Memo Pro and Classic models only).
 
First a word of explanation about the audio frequency headphones output. Our MHC products exclusively detect activity in the vicinity of 100kHz (way beyond the frequencies that even a bat can detect) and dramatically filter out low frequency background noise and vibrations - so how can they produce an audio frequency output for the headphones? The trick is to demodulate the amplified sensor signal first. It is a similar principal to how an AM radio works; the carrier is stripped away from it's amplitude modulations which occur at audio frequencies. The effect is to produce an audio signal which is very sensitive to fault signals (such as impacts and friction) yet insensitive to everyday noises and vibrations.
 
This method gives a much clearer sound than listening directly at audio frequencies and it also has the added benefit of sounding 'right' (ie not like electronically generated pings). Engineers tell us that they can intuitively tell what's happening from the headphones signal.
 
So why not listen for yourself to the three sound bites we've included on this page for a 'good' bearing, a 'bad' bearing and a 'poorly lubricated bearing' with lubricant being applied. Provided your computer is fitted with a sound card you can simply click on any of the relevant links below.
 
Of course there is a tendency for different people to interpret the same sounds differently and this is where the advanced signal processing and digital display of Distress and dB Level values comes into its own.

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speed of measurements

taking measurements video

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attaching sensors

attaching sensors video





 

 

click here to listen to a BAD bearing (wav file)

click here to listen to a GOOD bearing (wav file)

click here to listen to a LUBRICATED bearing (wav file)

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