MS2 3.0 Rev 2.92 testing issues

br1070 · Post by **br1070** » Tue Jul 21, 2015 5:09 am

Hi Matt,

I attempted to, but a couple of post up I posted an unfortunately large image of the output I was getting on the oscilloscope. To me it looked like some signal, but very noisy and I was not able to do much with it. Can you make anything out of that, or was I just measuring incorrectly?

Brad

br1070 · Post by **br1070** » Tue Jul 21, 2015 10:27 am

Matt Cramer · Post by **Matt Cramer** » Tue Jul 21, 2015 10:52 am

I couldn't tell what was going on there. I'd need a look with a smaller time / div setting.

br1070 · Post by **br1070** » Tue Jul 21, 2015 11:24 am

I see. It looks like it is measuring in the millivolt range though. Shouldn't it be closer to 5v ish. Could you give me some pointers on taking this reading. My knowledge of the oscilloscope is not as good as it could be. What points on the board to probe etc. I want to get this solved....I have been stuck on this way too long.

Thanks for your help,
Brad

Matt Cramer · Post by **Matt Cramer** » Tue Jul 21, 2015 1:31 pm

Start by probing TachSelect to ground for the input and TSEL to ground for the output. TSEL needs to be a 0-5 volt range. Millivolt readings are just noise.

br1070 · Post by **br1070** » Wed Jul 22, 2015 7:06 am

Hi Matt,

Something seems to be going on when i'm trying to get measurements. No matter where I probe on the board I get the same constant noisy signal. I tried measuring as you suggested and I just got a noisy signal. Any ideas?

Brad

br1070 · Post by **br1070** » Wed Jul 22, 2015 10:16 am

No matter what adjustment I make to the trim pots I still get no vr signal response on the oscilloscope or in tuner studio.

Brad

Matt Cramer · Post by **Matt Cramer** » Thu Jul 23, 2015 5:33 am

Do you have a good signal coming in on Tach Select?

br1070 · Post by **br1070** » Thu Jul 23, 2015 7:01 am

On the oscilloscope it just looks like noise to me. Also the noise looks similar on TACHSELECT and TSEL.

Matt Cramer · Post by **Matt Cramer** » Thu Jul 23, 2015 8:36 am

You'll need a good incoming signal. What sort of Stim are you using?

br1070 · Post by **br1070** » Thu Jul 23, 2015 10:49 am

Its the megastim 2.1

br1070 · Post by **br1070** » Thu Jul 23, 2015 10:52 am

Thats a 2.2 sorry.

Matt Cramer · Post by **Matt Cramer** » Thu Jul 23, 2015 11:31 am

Try changing the switch next to the RPM pot.

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MS2 3.0 Rev 2.92 testing issues

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