Questions concerning Understanding Signals Activity #1 and #2 results

tgif

After performing the Ground Test activity, from Understanding Signals, I get the results shown in the attached screen shot.
I do not understand the spikes on the left side of screen.
Shouldn't it be a flat line?

When I perform the Vin and Vdd measurements I get the following results:

Again, shouldn't these be flat lines?

I am using a Board of Education.
Wiring done per manual.

DonB

I got the same results. I think we are picking up some inductive signals in the hardware. I found if I turned the scope off and on again the spikes went away for a time, otherwise I got the same results as the lesson.

hover1

@tgif,

Since you haven't gotten a reply to the problem, I would suggest you contact Parallax directly at support@parallax.com . They don't always monitor the forum on a daily basis. I'm sure they want to be aware of any problems.

I am going to run through that activity to see what I get.

What version PropScope software are you using? Ver 2.02 is the latest.

http://www.parallax.com/go/propscope

tgif

Thank you for the responses.

hover1:

I am using v2.02
I will contact service.

DonB:

I also got the exact same results that you did upon turning it off/on. Spikes returned soon after.

hover1

Just got a chance to pull out my Prop Scope and went through the activities.

Verdict: I got clean flat lines on both activities with Ver. 2.02 and 2.03 software. No anomalies like those that were shown

Hope you get a better answer from Tech Support!