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Slot car motion sensor
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Please be positive and constructive with your questions and comments.

Re: Slot car motion sensor

by Str8run on Wed May 26, 2021 8:34 am

Ok, I will later today. Thanks for hanging in there.

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Re: Slot car motion sensor

by Str8run on Wed May 26, 2021 10:07 pm

The message board won’t let me. Keeps telling me the file is to big.
Do you have an email address?

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Re: Slot car motion sensor

by adafruit_support_bill on Wed May 26, 2021 10:18 pm

If the photo app on your computer does not support re-sizing, there are plenty of free on-line apps that will do it.

About 800x600 is usually a good size.

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Re: Slot car motion sensor

by Str8run on Sat May 29, 2021 11:51 pm

18B1E2D3-E646-48B7-B4BA-89448A6ECB50.jpeg
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ok
Here it looks like I got something going. Was able to upload some pictures. Tell me if you got them and if they are helpful. Remember this is just a mock up. No real circuit board yet. It’s all in test phase.
My big question is the grounds. Look at the drawing I did of the wiring as it is how I wired it. I’m not sure where the trigger at the timer relay gets it’s ground from. I plugged it into the same ground as the motion sensor are. Is that correct?
Attachments
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Re: Slot car motion sensor

by adafruit_support_bill on Sun May 30, 2021 6:33 am

The photos are not in focus so I can't see much detail. What kind of transistor is that? It doesn't look like a PN2222.

I’m not sure where the trigger at the timer relay gets it’s ground from. I plugged it into the same ground as the motion sensor are. Is that correct?

That is correct. All the grounds should be connected together.

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Re: Slot car motion sensor

by Str8run on Sun May 30, 2021 1:36 pm

The transistor is part number is PN2222A
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Re: Slot car motion sensor

by adafruit_support_bill on Sun May 30, 2021 2:05 pm

Assuming that all those wires are going where they are supposed to, you should see something close to battery voltage at the base of the transistor when there is nothing in the beam. Once you break the beam, that should go down to about zero.

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Re: Slot car motion sensor

by Str8run on Thu Jun 03, 2021 8:50 pm

That’s not what I’m getting. Here is where I’m at. At the base of the transistor (#2) I have 166mv with the sensor uninterrupted. When I break the beam I get 1.0mv. At the pin #1 which is going to the trigger relay I have battery voltage, weather the sensor is interrupted or not.
What could be wrong. Please send more information

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Re: Slot car motion sensor

by adafruit_support_bill on Fri Jun 04, 2021 5:32 am

What is the voltage on the red wire of the break-beam receiver? It should be the same as the battery voltage.

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Re: Slot car motion sensor

by Str8run on Fri Jun 04, 2021 8:27 am

Yes that is correct. Both red wires from the motion sensors. One from transmitter and one from receiving side are tied together and go directly to the battery. I probed each individual one about an inch from the sensor. Both are reading 4.7v.
Take note. I am using 2 pancake batteries for my supply. I don’t think that’s hurting me, agree.
What can we check next?

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Re: Slot car motion sensor

by adafruit_support_bill on Fri Jun 04, 2021 8:35 am

Disconnect the white wire and measure the voltage on that - first with nothing in the beam, and then with the beam broken.

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Please be positive and constructive with your questions and comments.