Does anyone here use an oscilloscope for diagnosis? If so, what model do you use, or have you used? I am looking at these USB oscilloscopes that are around $100 but I've never used one before. Not sure if it's worth it. ???

 

I use a Pico scope. However if you are new to using a scope take a class and buy a Snap on Vantage Pro. They can be had used for about $1000-$1200. The VP is hands down the BEST scope for beginners to use. Lots of connector views and how to's built in. If you are not an automotive professional, I really dont see what you would need a scope for.

 

I'd like to get one for diagnosing ignitions pre-obd2 and sensory devices. I'm not a "professional" as in I don't work in a shop, and I have no plans to. But any tool I can use to check the health and operation of electronic components and being able to spot problem sources is a plus for me. I have my eye on a USB pico scope with 5 channels. I have several books that show how to use one for diagnosis, but I'm not sure if a pico scope would serve well for that purpose or not.

 

A Pico scope is considered the best in the biz. But at 3k it is not something for casual users(unless you have money to through around) it also has a steep learning curve. You should already be familiar with scope usage before purchasing a Pico setup. If you are going to use the scope casually then I honestly cannot give you a good suggestion as far as price. However i stand by what i said initaly The Snap On scope is the best for beginners and is just as capable as the Pico. It simply has less channels.
I dont know how well lower end scopes perform.

 

i have a real multi channel 50mhz oscope from HP....overkill for anything electrical on a car.

 

http://www.eevblog.com/2010/03/31/ee...00mhz-ds1102e/

We did this mod to my buddies O-scope and it worked wonders also he had the version with the logic analyzer.

 

going from 50mhz to 100mhz for car applications will do nothing. there isnt anything switching on and off anywhere near that fast in a car.
you can use a handheld 2mhz scope for car troubleshooting.

 

This is one of the stand-alone scopes I was looking at: http://www.tequipment.net/Velleman_HPS10SE.html

It has a 2mhz bandwidth. For a little more, it can be had with 12mhz bandwidth. I'm not sure if this would be usable, in comparison to a USB DSO that can store a lot of recorded data; I'm not sure if recorded data is even necessary, or if this device can record.

 

thats a good option they go for around $160 new on ebay.
http://cgi.ebay.com/Velleman-10mhz-H...item5adb60e3a4

Ive also been thinking about getting one of these to carry in my smaller toolbox
http://www.robotshop.com/seeedstudio-dso-nano.html

 

I like that seeedstudio DSO. Is 1mhz enough bandwidth? It doesn't say how many samples per second it takes.

 

1 Msps... seems sufficient I suppose

 

this is why i still have a straight analog oscilliscope....no sampling rate its real time.

the speedstudio dso takes 1 Msps (1 mega samples per second) at 12bit and has an analog bandwith of 0 - 1mhz ......for car sensors this is more then fast enough

 

Right. In fact it would be a poor choice. the bandwidth is too high and will create phantom glitches and "white noise"

 

Problem with that is you cannot review the info and catch intermittent problems. A modern DSO is plenty fast and the sampling rates are more than enough for any car.

 

far from a poor choice if you know how to use an oscilliscope properly. digital scopes since they do have a sampling rate and a delay till display they can miss spikes but a random spike here and there usually isnt an issue for car electronics unless the spike is high enough to cause something to trigger.

 

There are dirt cheap clones of the seedstudio dso nano floating around. Especially if you're capable of assembling it yourself. I have one, but it's been rare that I've actually needed to use it.

 

correct....an analog scope if your not staring at the screen 100% you can miss something....for cars where your signal is pretty close to being on and off with a slight knee till saturation digital scopes work great and you can datalog and go back and graph later.

 

the only reason im using them is in testing of some of the ignition electronics ive built for my honda.

 

It does not matter how "good" you are with a scope. You will still get erratic signals that you will have to filter out if the frequency is too high. That is unnecessary work, and the reason why a labscope dedicated to automoitve use is the best bet. You do not seem to be very updated on Auto labscopes. the sample rate is extremely high. My Pico is 80 ms/s. But I forgot to ask how many channels your scope has. 50mhz is not very high if you have a 4 channel scope.(unless that is 50mhz per channel) My 2 channel scope is 40mhz. As for "spikes" this is also incorrect. I use my scope for diagnostic work, perhaps different for what you use your scope for. The Pico scope is an Automotive scope, specifically designed to capture any and all glitches or "spikes" regardless of how minute they may be. There are many occasions where these "spikes" will cause a drivability event ,but occur to quickly for the PCM to record any problem.

http://diagnosticnews.com/tech/autom...pecifications/



*Also you may be interested in knowing that a new Pico scope is on the market that is rated at 80mhz. This speed is necessary for Flexray vehicles that are starting to hit the market.

 

sweet link, I'll definitely have to take a look at that... but still, i am probably going to keep working on older cars only, so I'm still confused as to what I should get.

 

Again I cannot tell you, as a casual user, which is the best bang for your buck. But i still suggest taking a scope class for any scope you choose to use.

 

i've been using an Oscope for quite some time on both nissan's equipment and honda's equipment they provide at the dealer its not bad but i wish it could range faster and attempting to find some of the time and divisions in the book are kind of a pain in the ***.

i have been lately using a friends snap on scope and its quite a wonderful piece, time and divisions built into the module with what you are diagnosing. Probably going to be purchasing one soon, along with a cheaper scope just to play around with.

 

see if you can find someone with an analog scope to try....they are light years better then the digital scopes....most digital scopes sample in the ms/s there are some that get into the gs/s sampling and dont have such a delay and give you a waveform much closer to analog. try some real scopes most of the "automotive" scopes are overpriced pos