im not sure as to how to check them. could you please elaborate on how to do that
Put your meter on DC mode and put your black probe on your power headers ground and the red probe to pin 3, then the same for pin 16
look at that
16th pin shows up as -0,68
3rd pin as -10,81
Ok, well that’s good you found a quantifiable issue. You should see your full positive power at pin 16
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so i should just replace the wire that connects to it?
You should look for a problem between pin 16 and the power header, something isn’t right.
alright i’ll look at everything and update when i have something new
another question, if I connect the red probe to +12v and the black one to ground at the power header. what should show up? +12? for me it shows aproximately -0,68
Yep should be -12 and 12 at the power header.
So your problem isn’t your module, at least not yet =]
What are you using for a power supply? Sorry if you already mentioned it already but I didn’t see
Also, curious what kind of class you are doing this for? I never did anything this cool in school
FC microbus i’m checking it now, nvm im not sure as to how.
Nice, I have a couple of them. My first one I thought I had issues too but I was just trying to use an AC/DC wall wart (like 99% of wallwarts) but you need an AC/AC
almost a year ago I was asking stuff about how to power these modules and that’s when I made the PSU, I think I have the right adapter.
Oh no, I think you’re right, it’s a ac to dc psu. Godammit, I was so unsure about the power adapter so I ordered it from online where I think it said it was ac to ac but it has the dc symbol on the output. Well that’s a bummer. But a huge thank you for the help Ctorp, without you I would still be sitting here scratching my head as to what I’m supposed to do. When I finish these modules I’ll probably post it here or somwhere else.
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Hey! It’s a bummer but I bet you get it working right away with a new supply. Check out Jameco brand. And you have a multimeter now. In my experience (and many others in this forum) circuit problems almost always end up being simpler than how they first imagine it. Usually something silly!
Definitely post it up here when you finish!
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You just did!
Well, not quite. The first version of the VCO from Sam’s page would be pretty much the simplest 3340 testing circuit you could build.
Fortunately it sounds like you don’t need to.
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I did suspect the PSU 
As AO says you can’t get much simpler, they only alternative tester would be a pre-designed PCB for a VCO.
You actually could simplify Sam’s core VCO a little, e.g. by leaving out the TL072 and just being careful what you plug into the outputs (or omit the output jacks if you have a scope). But it’s only a little more effort to build the full circuit and then you have a module, not just a testing board.
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Yeah my simple PCB is my tester…
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