Test Equipment - Miniature Oscilloscope

[Rednaxs60]

Was browsing the various forum threads for my ECU upgrade/replacement project and came across a post where the fellow had purchased a small oscilloscope and put it together. He paid $25.00 USD for it. I decided that this would be a good addition for my test equipment so I went on Amazon.ca and found a similar already together unit for $35.00 CDN. It is a DSO 138 Oscilloscope that will provide additional information for troubleshooting and determining what a sensor is putting out. Here is a picture of the unit:

It has a 2.5 inch screen (on the diagonal). I purchased a power plug for it:

This plug can be configured for several different voltages. The oscilloscope needs 9 VDC and the unit on the 9 VDC setting puts out 9.2 VDC - acceptable.

I wanted to test the scope so I tried it on some TPS units I had available. TPS units are notorious for lack of good QA at the factories and even when new can be faulty. This is a test shot:

I wanted to see the voltage as I moved the TPS rheostat. I have done this with a voltmeter, but the scope is more precise and gives a better indication of the signal quality that a multimeter cannot duplicate; however, you use what you have.

The signal that is shown for this particular TPS unit was not bad. As i moved the rheostat, there were a couple of bumps going up to 5 VDC, but not as bad as a couple of other TPS units I have on hand. I was looking for the same voltage form through the entire range of the TPS. I had found a web site that showed a different wave form, rising from base to max voltage, but I could not duplicate it. Time and practice will help as well.

I'm looking forward to using this scope on the sensors on the 1200 to determine what each is doing, and making a case for it.

Thought I'd share this with the consortium.

Cheers

 

[julimike54]

Cool new toy!

 

[Steve83]

Love my scope! This one looks pretty neat, enjoy!

 

[desertrefugee]

I wish I had only paid $25 for my tektronix THS730. But I cannot complain. It has served me well.

 

[Rednaxs60]

I also have a Telequipment Type 43B (?) as well. Big brute so this newer one will suffice for the little stuff. Still learning how to use the big one.

 

[Ansimp]

:good:

 

[kerryb]

That's very cool, would it be something you would take on a road trip, or just have it in the shop for diagnosing issues?

 

[Rednaxs60]

For the shop diagnostic use. For a road trip - VISA and good towing package. Cheers

 

[wilcoy02]

I assume you saw the plastic case for this on amazon for $8.

https://www.amazon.com/s?k=DSO+138+Osci ... nb_sb_noss

 

[pidjones]

I'd like to have one, but have sooo many toys already. Might just haunt ebay for an old lab scope. 100 MHz would do me fine.

 

[desertrefugee]

99% of home tinkerers will never need an oscilloscope. The only reason that I ended up with mine is that one of my passions is vintage audio. Many of the units I acquire and flip are very needy. Scope is invaluable tracing down bad acting circuits. I can count on one hand the number of times I've felt I needed to apply it in an Automotive situation.

I did do an interesting survey once comparing the switching characteristics of breaker points versus electronic ignitions.