Author Topic: Testing the circuit  (Read 1323 times)

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jaabot

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Testing the circuit
« on: May 05, 2009, 02:08:36 PM »
Hello, another newbie question.

My son and I have completed the soldering. Thanks to the help from this forum, I think we have everything connected properly. I also have my shinny new multimeter, and we are now on the step about "smoke testing." I did the continuity testing and I think everything is OK. (it beeps if both probes are on ground, but no beep if one probe is on ground and the other on a power bus). I think that is good from what I understand.

So, in Admin's tutorial, after the continuity test, he says "If you put the multi-meter on the resistance setting, make sure all non-connected pins have at least 5 kohm resistance or you may have power issues."

Can someone elaborate on how to do this test? Does this means pins that are not connected to anything?

Finally, he talks about a 'smoke test': "This is when you power up your circuit with a power supply. Plug your circuit in, start the voltage at 1V and work your way up slowly to 6.5V."

Again, I am not sure how to do this. How do I start the voltage at 1V? Is this the setting on my multimeter? Or an I supposed to be able to limit the amount of power going into the circuit? If the later, how do I do that? We are using the 9v and 4AA battery combination. As far as I know, I cannot limit the power of those sources.

Again, my apologies for the simplistic questions. I appreciate any assistance. Thanks so much.

SmAsH

• Supreme Robot
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Re: Testing the circuit
« Reply #1 on: May 05, 2009, 02:22:50 PM »
basically you just set your multimeter to the (R) setting to measure resistance...
then find two traces that aren't supposed to be connected and put one probe on each.
the resistance SHOULD be more than 5Kohm if the traces are not connected.
if they aren't, it means you may have a short...
with the one volt thing, it is kind of hard to do this without an adjustable power supply....
you should be fine plugging your battery packs straight in.
Howdy

jaabot

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Re: Testing the circuit
« Reply #2 on: May 05, 2009, 04:53:04 PM »
OK. I'll try that.

I looked at Admin's post again and noticed he had some big fancy piece of equipment in the photo. i assume this was a variable power supply of some kind.

Thanks.

SmAsH

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Re: Testing the circuit
« Reply #3 on: May 06, 2009, 12:31:30 AM »
yes, that big thing in the picture does look like a bench top power supply. the only problem is the cost... they cost big bucks... unless you have a home made one
Howdy

jaabot

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Re: Testing the circuit
« Reply #4 on: May 06, 2009, 08:43:22 AM »
I think we'll hold off on that for now.

SmAsH

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Re: Testing the circuit
« Reply #5 on: May 06, 2009, 02:26:33 PM »
yeah, most of us who don't work for the navy like admin don't have all that fancy prancy stuff just get by with battery packs...
Howdy

• Supreme Robot
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Re: Testing the circuit
« Reply #6 on: May 29, 2009, 11:27:17 AM »
The fancy prancy variable voltage power supply is cheap and common. You can find it in literally every electronics related lab you'll ever see.

Pricing starts around \$30. Not needed for the \$50 Robot, but very very useful if you're serious about robotics.

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