Running Engine Compression Wave Form on DSO Nano DS201
britishtrident - 14/10/15 at 06:03 PM
I am quite please with this one the compression oscilloscope trace of a running engine on a tiny DSO DS201 Nano palm sized oscilloscope.
Unfortuneately my DS201 is the version that can't save BMP files so this image was made by putting it on a photo copier !
The real image on the scope looks much clearer
The sensor used was a cheap Chinese made industrial 2.5 mpa sensor which cost under £15 one or two other bits and pieces were needed to make it work
but total cost was under £25
Description
Locost Running Compression
Link to explanation on web http://www.counterpersontraining.com/index.cfm?go=lms.module&moduleid=33&mode=train&topicid=223
Another image of similar waveform caputured with the official Picoscope sensor http://www.atsnm.com/assets/running-compression-1.jpg
http://www.priggen.com/WPS500X-Automotive-Pressure-Transducer
rf900rush - 15/10/15 at 07:16 AM
Wow what a neat device. why did I never think of it?
I guess by the scope sample rate being relitivley slow (< 1m samples) one could use a cheap microcontroller and cheap LCD screen.
A bluetooh to android tablet/phone would be great.
Was the other part include a colourtune sparking part?
MikeRJ - 15/10/15 at 11:13 AM
quote:
Originally posted by rf900rush
I guess by the scope sample rate being relitivley slow (< 1m samples) one could use a cheap microcontroller and cheap LCD screen.
The DS201 Nano is a cheap microcontroller and LCD screen 
e.g. ARM DSO DSO201 Portable Digital Storage Oscilloscope DIY Kits
ge
.
If you want really cheap, and you aren't averse to building something yourself, Handheld DSO138 2.4 inch TFT Digital
Oscilloscope Kit DIY Parts 1Msps w/ Probe may be of interest.
Or you can get a two channel, 20MHz USB scope for under £50
here
[Edited on 15/10/15 by MikeRJ]
britishtrident - 15/10/15 at 11:49 AM
A few construction details all the parts bought off the web (mainly eBay) with the exception of the transducer all parts were from UK suppliers.
Description
Transducer bought from eBay seller
DSLTD15 link to ebay shop
Transducer has three connection Power (red) +5V , Signal (yellow) , Common Ground (Black)
Transducer requires 5V supply --- I used a cheap dc step down convertor off ebay which I can either power from the car or a 9v PP3 battery however I
read elsewhere on the web that these transducers aren't particularly voltage sensitive and that a a simple voltage devider resistor pair would
work.
The step down voltage converter I used was the same as this one DC/DC Converter Regulator 12V Stepdown to 5V 3A 15W Car Power
Supply Module UK
The Sealey VS1601 airline adaptor is easily and cheaply available from a number of sources
here is a link to one
It is pretty important not make sure that the connections under pressure are safe -- ie use proper pipe thread connections screwing M14x1.25 into a
1/4" BSP thread is not safe.
Originally I tried using the connector hose from my old style compression tester but the hose blew out, using the Sealey adapter works a treat.
britishtrident - 15/10/15 at 12:04 PM
quote:
Originally posted by MikeRJ
quote:
Originally posted by rf900rush
I guess by the scope sample rate being relitivley slow (< 1m samples) one could use a cheap microcontroller and cheap LCD screen.
The DS201 Nano is a cheap microcontroller and LCD screen e.g. ARM DSO DSO201 Portable Digital Storage Oscilloscope DIY Kits
ge.
If you want really cheap, and you aren't averse to building something yourself, Handheld DSO138 2.4 inch TFT Digital
Oscilloscope Kit DIY Parts 1Msps w/ Probe may be of interest.
Or you can get a two channel, 20MHz USB scope for under £50 Hantek 6022BE PC-Based USB Digital Storage Oscilloscope 20MHz Bandwidth
2 CH | eBay
ocument
[Edited on 15/10/15 by MikeRJ]
The DS201 Nano is actually a cracking bit of low cost kit once it is flashed with the Ben-F firmware which is public domain.
It is cloned by several different Chinese manufacturers and the versions vary mine has a very tough steel case but no external memory slot.
Without the Ben-F firmware it would be useless. If only it was based on a 7" tablet it would be really world beater.
I also have a low cost Hantek USB scope the 8 channel 1008b which came with a a capacitive ignition probe, although it has 8 inputs in reality
it only useful for at most 3 channels at a time, but it is fine for looking at ignition and crank sensor/cam sensor/ABS waveforms.
The Hantek 1008 dosen't work well with this type of pressure transducer probably because the impedances are nor not matched.
[Edited on 15/10/15 by britishtrident]
britishtrident - 19/3/16 at 01:45 PM
Nice Clean running compression using the Owon Scope
runningcompression
