|12-22-2011 09:24 PM|
|beaker60||yea,,,that is another great thing about the verdict,,it's a wireless unit,,but thinking about it,,,for 12,000 dollars,,I would like to get a dinner and maybe a floor show,,but you're right,,how do you get the cables to run from the engine compartment to the front seat,,,although,I will admit,,I don't do to much,"on the drive"diagnostics with a lot of what I work on,,mostly in the shop,in a stall.I had a chance last year to buy one of the old Sunn engine analizers,,,and I wish I would have had the money,,,they were very antiquated,,but when it came to carbureted,,basic distributor,,engines,,,they really were pretty cool.|
|12-22-2011 08:07 PM|
Older Snap-On Counselor II (MT3000 or MT3000A) is both extremely affordable and wonderfully equipped for automotive work if you get all the accessories with it. Unlike the more modern automotive scopes, the Counselor series does not have "known good" patterns stored in memory for various electrical devices. It's also not very portable. It will run on 12V, so you "could" take it along on a test drive--but how do you get the cables from engine compartment to passenger seat?
Here's a screen shot of the 'scope connected to read amperage draw of the electric fuel pump of my '88 K1500 work truck:
Looking closely at the "humps", you'll see that they are similar but not identical, and the pattern repeats every eight humps. This shows that the fuel pump motor has eight bars on the commutator. A motor with twelve commutator bars will have a repeating pattern every twelve humps.
The vertical position shows that the fuel pump draws just under six amps average, with a peak of 6.444 amps.
By "freezing" the pattern, and using the cursors--the solid and dotted horizontal and vertical lines--I can tell that it takes 9.42 milleseconds for all eight bars to peak, which would be one revolution of the electric motor. Simple math tells me that one revolution in 10.16 milleseconds is equivalent to (60,000 / 10.16 = 5905) 5905 RPM; a reasonable speed for this fuel pump.
Since the average amperage, the shape of the amperage peaks or "humps" is reasonably symmetrical, and pump RPM are proven to be good, and the fuel pressure is acceptable, I know for sure that this pump is in fine condition.
Just a quickie example of how wonderfully handy an automotive oscilloscope is.
|12-22-2011 07:09 AM|
|beaker60||I don't own one,,,but I have endless access to the Snap-On Verdict,,,the machine is incredible with the abilty to scope,,in seperate screens,,as well as cylinder comparison tests,,but like others have said,without training on one of these it is extremely complicated.It is not beginner friendly,,you have to have some time with it before you can utilize it in the manner it was designed for,,and like others have said,,,I wish sometimes I could get my hands on an old-school O-scope,,,especially for non-EFI engines.The verdict has made my diagnostic life extremely easy with all of the new stuff,,,but for my carburated engines that I have built,,it helps,,,but it doesn't do what I'm looking for.And also,,,the cost of the Verdict,,,all soft-ware included,,puts it out of my reach,,,the whole unit,,with everything,,,$12,000.00,,,Holy YOW.|
|12-21-2011 05:44 PM|
|LATECH||Thanks Farna. I saved it as a file and With christmas coming I will have time to sit and read a bit.|
|12-21-2011 04:59 PM|
I ran a quick search and came up with this website:
It gives the general specs and has a link to a manual.
|12-17-2011 10:37 AM|
|T-bucket23||8 channel Pico is the best I have used for automotive work. I don't own one but have used one many times. I have a old bench scope but it is not designed to be as portable as automotive work requires. I have used it a few times to check waveforms but it is really to big.|
|12-17-2011 10:09 AM|
Most of the experience I have with DSOs are signal integrity checks in the Ghz range. Regarding the DSO in question I would want to know it's time base resolution and memory depth. Without a manual you are shooting in the dark. Have you tried a Yahoo search for the manual?
|12-17-2011 07:39 AM|
Wow. Nice setup Mark. It is nice to be able to verify all the components and functions. Makes perfect sense. You could even heat the o2 sensors with a propane torch to test . I have done this to verify wire colors on them in the past. The aftermarket doesnt allways label things well when it comes to wire colors on universal fit stuff.
I like your style man.
|12-16-2011 09:14 PM|
I looked for awhile for one because I do a lot of EFI conversions and sometimes had issues with electrical noise. Really lucked out one day at the Pawn Shop and got a Mac Osiliscope for cars, $3500 retail for $375. I have learned a lot about where to and where not to run certain wires in the EFI system because of it. Now I hardly use it because I had made all the mistakes...
Nice thing about it being built for cars is it has actual graphs to show what proper signal should look like, then compare yours!
May as well show my EFI test bench, I build a harness from a Junk Yard pull and complete system on the bench, hooked up to 12 volt, drill running distributor, vacuum pump on MAP sensor while emulating and recording data from my laptop. This way I know it all works when installed and all parts are good! Chip has no error codes because of things missing like EGR or Charcoal Canister Purge or Air pump...
Actually I have one system running here hooked up to the intake on bench, my ECM for this with on light, CEL, Fuel Pump and O2 sensor are on the wall other sensors you see with rear distributor turning by drill, sparking one plug off coil and another ECM running of a simulater and the Osiliscope checking pulse width on injectors wires because I had run them differant then Chevy rear distributor to an engine with front distributor...
|12-16-2011 08:37 PM|
Actually I like the scope in the Modis, it was pretty easy to use, just snap on priced..
I want to find a good alternative,the pocket DSO is cute but tough to see, I am going to explore a slightly larger model of somekind.Thing is, I dont have to deal with it as a necessity as a field technician , using a scanner with Bi directional controls helps me narrow down most OE trouble that crosses the doorway.And with OBDII code definitions are pretty definitive and make it simple to arrive at a conclusion as to what the fault is.
Last time I needed an O scope was for a 94 Mitsu 3000.Code 12 for maf was stored with no MIL. The MAF was dead. It wouldnt Idle when warm as the IAC would slam shut. Seems an O scope is needed more as a diagnostic tool for OBDI cars than OBDII, well at least untill you start looking at CAN messages. But then again bi directionals are a big help to a flat rate guy.
|12-16-2011 08:21 PM|
|12-16-2011 07:47 PM|
Meters only are as fast as there sampling rate, not real time like an O scope.
There are quite a few O scopes for sale for under 500 these days.
The snap on Modis has a scope, yeah they are real affordable
|12-16-2011 07:38 PM|
|TurboS10||I have never had an actual oscope. I have a meter with a built in scope function but it only gives you frequency. It has been sufficient for me on checking trigger frequency.|
|12-16-2011 07:00 PM|
ARM Digital Storage Oscilliscope
Has anyone seen one of these. I bought one off of Evil Bay. It is a little tough to use (it is small and hard to see) And I dont fully understand it. It did not come with a manual, but I know enough about O scopes to dial in the time/voltage per Div , and such.
Just wondered has anyone seen these and what do you like / Dislike.
One thing I dont like is the back is an adhesive panel and you cnt replace the battery without getting pretty tough on it by pulling the adhesive back from it.It had a Li Ion battery and I have succesfully charged it by plugging it into a USB port on my PC, so its all good for now.
I bought mine at Hop Sing's House of Oscilliscopes.
Let me know your thoughts.