Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help



Go Back   PeachParts Mercedes-Benz Forum > Mercedes-Benz Tech Information and Support > Diesel Discussion

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 11-02-2021, 12:12 PM
Registered User
 
Join Date: Sep 2006
Location: Middle TN
Posts: 4,154
Does anyone use an oscilloscope

I've been looking at the Pico 2000 series especially for my cars with sensors and electronic ignition. They are $150 to $250 depending on 2 or 4 channel and sampling rate etc. Any opinions?



https://www.picotech.com/oscilloscope/2000/picoscope-2000-manuals


https://www.youtube.com/results?search_query=mechanic+mindset

__________________
85SD 240K & stopped counting painted, putting bac together. 84SD 180,000. sold to a neighbor and member here but I forget his handle. The 84 is much improved from when I had it. 85TD beginning to repair to DD status. Lots of stuff to do.
Reply With Quote
  #2  
Old 11-02-2021, 06:13 PM
Registered User
 
Join Date: Oct 2005
Location: Knoxville, TN
Posts: 437
I use one rarely.
I've got an ancient B+K Analog unit, and one of these little dinky cheap things:
https://www.amazon.com/gp/product/B079CPDVRG/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

I don't need it for much, but the few times I'm troubleshooting a pwm signal like tach, fuel injector pulse, and things of that nature it has been super helpful and at the price point its hard to go wrong, because if I blow it up, its not a huge loss.

The big downside is it does not have any kind of battery, so I taped a 9v batter with a little adapter to the back so I can run it without needing a power source.
__________________
1982 300D (w123, "Grey Car")
1982 300D (w123, "Blue Car")
2001 Ford F150 "Clifford" (The Big Red Truck)
1997 Dodge Ram 2500 12V Cummins
1996 Dodge Ram 2500 12V Cummins
Previous Vehicles:
1995 E300D, 1980 300SD, 1992 Buick Century, 2005 Saturn Ion
Reply With Quote
  #3  
Old 11-02-2021, 07:33 PM
Diesel911's Avatar
Registered User
 
Join Date: Sep 2007
Location: Long Beach,CA
Posts: 51,043
On a gasser and not a Mercedes. 2 months ago I had issues with my Van that turned out to be in part 2 of the sensors. The Coolant Temp Sensor was in a place where it could not easily tested without tapping into the wires or having another connector and info on what reading I was supposed to get at what temp and there no way to read the temp easily either.

The TPS has a similar issue. But I was able to get at that but the test was kind of inconclusive because the specs are kind of loose.

It turned out to be easier to buy some new ones on eBay and wait for them to arrive. The main issue was the Coolant Temp sensor and a new one fixed that and the intermittent code that the TPS had been doing even though I had previously replaced the TPS finally cleared with the newest one I put on.

What I learned is you need to have a good solid way of connecting what ever it is you are going to hook to the testers to test them and you need the specs to compare your readings to.
__________________
84 300D, 82 Volvo 244Gl Diesel
Reply With Quote
  #4  
Old 11-03-2021, 10:34 AM
ykobayashi's Avatar
Registered User
 
Join Date: Jun 2005
Location: Irvine, CA
Posts: 1,261
The Pico 2000 looks like a nice deal at $150. Four channel is good if you need to look at four signals at once. Need usually means they are interacting and related so you have to check syncing. Like a sensor input for a particular actuator output. Or parallel logic signals. Rarely do I need four channels. I use a RIGOL 1054 which is also very cheap. It has four channels but I never use all of them.

Most of the electronics I work on is one input and one output. You put the sensor input on channel 1 and look at the amp output on channel 2 and check their relationship. And even that, you probably only need to check one channel at a time to diagnose a fault. Two channel is good if you want to see the exact input level the amp is switching the output at. Good if you want to establish a connection between cause end effect. So I say four channels if you are working on engineering and you’re studying synchronous interactions between four signals. Two for doing basic diagnostics.

The second thing I’d look into is how good the software is on the pico scope. Software will make or break this thing. It’s pretty hard to get the hardware wrong on something like that but the software can make it either a joy or horror to work on. Check forums where people review the thing like EEVblog. You want the opinion of people who actually use it.

The last issue with these things is system upgrades. That’s the Achilles heel of PC instruments. You upgrade your pc and OS and your scope becomes a brick. I literally have win98 machines I keep to run old tools I got in 1998. It becomes quite a pile of laptops.

I guess the second issue about this stuff is how you’ll use it. Balancing a laptop on an air cleaner while a car is running is a hassle. Running cables around the engine is a hassle. Having too many dongles to keep track of is a hassle. My personal opinion is pc based stuff works well on the bench. In a rough environment I like self encapsulated things like armored scopes and meters. Although while doing field service it is easier to bring a usb device since I already may have a laptop. They’re really good like a Swiss Army knife - it’s good to have in your pocket just in case but if you have to use it regularly it is better to have a dedicated screwdriver, saw, knife etc.

Ok those are my opinions. I don’t use a scope much on the diesel cars. I guess I look at tach signals sometimes. It’s funny after spending my career on electronic design I choose to drive the most unelectronic car on the planet. It’s like an anti Tesla.
__________________
79 300TD “Old Smokey” AKA “The Mistake” (SOLD)
82 240D stick shift 335k miles (SOLD)
82 300SD 300k miles
85 300D Turbodiesel 170k miles
Reply With Quote
  #5  
Old 11-03-2021, 11:52 AM
Registered User
 
Join Date: Aug 2010
Location: Sacramento, CA
Posts: 3,115
Looks affordable compared w/ lab scopes like Tektronix. For automotive and most mechanical things, 20 MSps is probably sufficient, so don't pay more for the the 1GSps unless doing RF type measurement. I have a Fluke Scopemeter 123, which retails for >$1K, though I got it free via a magazine lottery. Might have been a prize since a glitch as the battery won't charge, even a new battery pack I bought, but I have always used the AC adapter. I don't recall even using it for my cars and would only be for a few things like looking at a crank or camshaft signal. Mostly used it in my day job of engineering. Most automotive things I use my free Harbor Freight multimeter (keep one in every car). Rarely on my 1985 M-B since the engine bay doesn't have anything electrical except the starter motor, glow-plugs, and relays (AC clutch, radiator fan).

You can do most monitoring on a 1996+ gas car w/ an ELM327 via the OBDII port. Cost <$10 on ebay or Amazon. Bluetooth to a smart phone and run free app like TorqueLite. You can time-plot O2 sensor signals, read fuel trims, read and erase codes, and such.
__________________
1984 & 1985 CA 300D's
1964 & 65 Mopar's - Valiant, Dart, Newport
1996 & 2002 Chrysler minivans
Reply With Quote
  #6  
Old 11-03-2021, 01:41 PM
Registered User
 
Join Date: Oct 2012
Posts: 5,924
Looking around a few year back .Some scopes came up on Ebay as highest bids. Hard to remember now other than it was very very cheap.

Must be very little demand I thought at the time. Not required by me often but nice to have one for the times they are.
Reply With Quote
  #7  
Old 11-03-2021, 09:13 PM
Registered User
 
Join Date: May 2020
Posts: 69
I have many oscilloscopes and other pieces of test equipment of various types due to work, but my by far favorite (and cheap-ish used) scopes to use are the old Tektronix 400, 2200, and 2400 series. These guys have a complete list with details: https://w140.com/tekwiki/wiki/Main_Page . I'm a big fan of finding them used on ebay ("Used" condition - implicit 30 day warranty) and one can have a very capable, very accurate, and great use use scope from $60-150 for something analog. They also have full service manuals with schematics. I use a digital 2440 with tekmate for glitch detection and saving waveforms.
Reply With Quote
  #8  
Old 11-03-2021, 11:21 PM
250 Coupe's Avatar
Middle Aged Member
 
Join Date: Mar 2004
Location: Des Moines, WA
Posts: 927
I have the Hantek 1008. 8 inputs sounds cool but it does reduce the resolution. Kinda wish I’d opted for a pico scope.

You might check out the gadget playlist on YouTube, https://youtube.com/c/theGADGETSplaylist and if you opt for a Hantek scope, check out optional software at HScope App - USB Oscilloscope on Android

Michael
Reply With Quote
  #9  
Old 11-04-2021, 04:46 PM
Registered User
 
Join Date: Aug 2010
Location: Sacramento, CA
Posts: 3,115
Quote:
Originally Posted by nastala View Post
... my by far favorite (and cheap-ish used) scopes to use are the old Tektronix 400, 2200, and 2400 series.
I've use a lot of lab O-scopes over the years. The older Tektronix worked well except their knobs were a bit chintzy and would need retightening with an allen wrench. The later ones with digital spinny knob and pushbuttons seem more reliable, and I like the half size versions for portability, with same familiar front panel. For reliability, it was hard to beat the old H-P O-scopes. Like all old H-P instruments, the knobs gave a firm assuring clunk, similar to shutting the door on our old M-B cars. For automotive testing, any old O-scope should be sufficiently fast.
__________________
1984 & 1985 CA 300D's
1964 & 65 Mopar's - Valiant, Dart, Newport
1996 & 2002 Chrysler minivans
Reply With Quote
  #10  
Old 11-04-2021, 07:42 PM
250 Coupe's Avatar
Middle Aged Member
 
Join Date: Mar 2004
Location: Des Moines, WA
Posts: 927
Thought I'd add my scopes to the list, starting with my first which I still have and in fact used to test the tach amp in the 300SD a few months back.

The Radio Shack 22-310 Probe Scope! Super low resolution. Tiny Buttons. Runs on a 9 volt battery. It did show a square wave out of the amp which was all I needed to see. Then there's the Tek 464 storage scope which has that scary thump and flash when it erases the trace, a B&K 1420 which can run off an internal gel cell although I've never had a battery installed and a Siglent SDS 1202X-E which I was using today to calibrate a Heathkit IG-72. Oh, and the Hantek 1008C. Which I've not used much.

Michael
__________________
Usta haves '69 250/8, '76 280C, 1971 250C 114.023, 1976 450SEL 116.033
Current have, 1983 300SD 126.120
Reply With Quote
  #11  
Old 11-04-2021, 10:10 PM
ykobayashi's Avatar
Registered User
 
Join Date: Jun 2005
Location: Irvine, CA
Posts: 1,261
Wow Michael, I had to look up the Radio Shack 22-310 Probe Scope. I must have missed this when it came out. Interesting device. I have a tiny voltmeter probe that looks kind of like that but it’s only a DVM…from the 1980s.

It looks like Hantek has a USB scope probe that works with a laptop for $60.

Snapon diagnostics had some nice automotive scopes when I last looked many years ago. Vantage I think the name was. It was like a slow lcd strip chart recorder in a rugged box. $$$ though.
__________________
79 300TD “Old Smokey” AKA “The Mistake” (SOLD)
82 240D stick shift 335k miles (SOLD)
82 300SD 300k miles
85 300D Turbodiesel 170k miles
Reply With Quote
  #12  
Old 11-05-2021, 05:14 PM
Registered User
 
Join Date: Sep 2006
Location: Middle TN
Posts: 4,154
I've wanted one for a long time recently bought an 86 911 and came across the picoscope here. Never really needed a scope but remember when a friend who owned a shop bought a huge Sun Scope back in the 80s. Looks like the pico will do most if not all things the old Sun would. Would like to figure out a way to set O2 on the 911 as it's important when dealing with the fuel injection.

https://www.youtube.com/watch?v=L1jJpLzshP8&list=PLESd2KXwHSVKKl3FxYSFB3rGKZTsfWpQp&index=37

I'll look at some of the forums re various scopes.
__________________
85SD 240K & stopped counting painted, putting bac together. 84SD 180,000. sold to a neighbor and member here but I forget his handle. The 84 is much improved from when I had it. 85TD beginning to repair to DD status. Lots of stuff to do.
Reply With Quote
  #13  
Old 11-05-2021, 08:04 PM
250 Coupe's Avatar
Middle Aged Member
 
Join Date: Mar 2004
Location: Des Moines, WA
Posts: 927
I had one of those giant Sun diagnostic center things. Vacuum gauge, scope, volt/ohm meter and a bunch of other stuff. Kinda wish I still had it. I left it in the rafters of the shop when the 2nd wife kicked me out.

A scope is a really cool device for trouble shooting and the pico’s are a good choice for automotive as the software is designed for that use. The Hantek’s are less expensive but the software leaves a bit to be desired.

By setting the O2, do you mean adjusting the fuel mixture? I use a Gunson Gas Tester to set CO on my carb vehicles. It’s kinda clunky and may not be available any more but it does work. I once nearly set off the evacuation alarm at the testing station with the 280C idling in the bay with the roll up doors open. If you are reading the lambda sensor, a scope might help but I’ve never tried so can’t help there.

Michael
Reply With Quote
  #14  
Old 11-05-2021, 10:23 PM
Registered User
 
Join Date: Sep 2006
Location: Middle TN
Posts: 4,154
On those old fuel injection systems, there is a idle mixture setting. I don't know whether an O2 sensor could be used to set it or not.

I have a 78 Datsun Z and the 86 Carrera where it is required. I hope to have both as daily drivers by the end of next year - along with the 85SD and 85TD. None have to be show cars but everything mechanical has to work and paint needs to be decent.
__________________
85SD 240K & stopped counting painted, putting bac together. 84SD 180,000. sold to a neighbor and member here but I forget his handle. The 84 is much improved from when I had it. 85TD beginning to repair to DD status. Lots of stuff to do.
Reply With Quote
  #15  
Old 11-05-2021, 10:57 PM
250 Coupe's Avatar
Middle Aged Member
 
Join Date: Mar 2004
Location: Des Moines, WA
Posts: 927
If you were looking for a semi permanent thing to keep an eye on the mixture, you could install a wide band O2 sensor and gauge kit. Welding a bung in the exhaust for the O2 sensor is the permanent part, the gauge can be installed or wired to a lighter plug for temporary use.

Michael

Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -4. The time now is 11:09 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2024 Pelican Parts, LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page