That’s right. Here’s a video you might want to check out:
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I agree with others here, it seems like you have a short between +12V and ground.
It could be through the ICs as you might have blown them up when you initially reversed the power polarity.
Try removing the ICs and plugging the power in.
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So I have continuity between all of the ground pins and both +12V pins. There is not continuity between the +12V and -12V and there is not continuity between -12V and the ground pins. I checked all of the joints and there are not any bridges. I tried removing the solder from all of the ground pins so they were no longer bridged and checked again. I still have continuity between all of the ground pins and the +12V. I tried removing both IC’s and plugging the module back in. The microbus +12V LED still goes off.
There’s no point in plugging things in while you have a short to ground.
The short isn’t necessarily at the power connector. If the circuit is essentially the same as the schmitzbits one linked above, then probably +12V is used only at the IC power pins and the top of one pot, are any of them close to something connected to ground? E.g. maybe an IC has an unused pin next to the +12V pin which is connected to ground. A bridge there would explain it. Without seeing the exact circuit diagram and board layout I can only guess. But that gives a pretty small number of places to check. If you can convince yourself the bridge isn’t any of those places then it’s got to be at the power connector, and it sounds like if that’s the case you have no option but to remove it and try again.
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I just took out the IC’s and plugged it back in since Antoine recommended that. I just wanted him to know I had tried that. Otherwise, totally agree.
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The 10µF capacitor between +12V and ground might have gone short when you plugged the power in backwards, if it was a polarized capacitor, you might want to remove that for a try.
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Tried replacing it but the +12V still shorts to ground. I think my next step is to remove the box header again and try replacing the eyelets. 
The “eyelets” are not the problem — the problem is conductor where it shouldn’t be, not no conductor where it should be.
In case you don’t know, the way to remove the header is to cut or pull the plastic part away until you’re just left with the pins and then individually unsolder them.
Once the header is removed DON"T solder a new one on immediately. Do a check for shorts between +12V and ground (and while you’re at it, between+12V and -12V and between -12V and ground). If the short is still there, the problem may still lie elsewhere at one of the ICs or pots. Find it and fix it before putting the new header on.
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I didn’t know that was the way to remove the header. Thanks for the information. What I did before was use a desolder pump on the pins, then some wick to get anything left and then heated up the pin, pushed it through, and removed it. I didn’t cut the plastic away first.
I followed your instructions on removing the header and it worked great. I cleaned up any remaining solder with the wick. I checked the pins and I no longer have any shorts between any of the pins. So somehow when I put the new box header on the solder found it’s way to the other pins. I wonder if this happened on the topside where I couldn’t see below the plastic?
Is there anything I can do to help so that the solder doesn’t go to the other pins under the box header? Should I use pins instead on this module? Thoughts?
Thanks again for your help!
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It’s unlikely that you’ll create a short on the other side of the board while soldering the header.
My guess is that @ChristianBloch was right and you had a short here:
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I think I fixed it! I re-did the box header, soldered the ground wires together, soldered the 2 +12V pins together, soldered the 2 -12V pins together. I had to run a wire from the -12V pins to a nearby resistor. I am receiving +/- 12V on the tl074 chip. Nothing is grounding out on the box header. I plugged it in and my +12V LED stays lit. I just don’t know if it works as I don’t have a way to test it until I get the midi/cv module.
Thank you all so much for your help. I learned so much having to do this.
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hey pop flier! how did it turnout?
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I THINK it is working now, but I don’t know for certain?? I was able to follow the instructions @fredrik @sebastian and @analogoutput provided and bridged the adjacent pins. I had to run a wire from the -12V to a nearby resistor and I am getting the proper voltage on the TL074. I plugged it in and when I turned the resonance and big knobs the lights would flicker so I assume that means it’s working? I do not have a way to test it any further as I do not have a clock source. (I’m waiting for the MIDI / CV module.) So for now everything sits here in a box 
Thank you for asking!
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You need a clock source for a filter?
Maybe I missed something, but I think you can already test your filter and all the other stuff. You just need to connect the VCO to power and it will put out sound! no need for a MIDI to CV. I mean, you can only tune it with the tuning knobs and not really play melodies, but you can already send it through the filter and check if it is working.
My keyboards are all midi controllers, expect for my jp8000, which is being serviced at the moment. Last week I grabbed a pair of crappy throw away headphones and connected it to one of the wavs on one of the vco’s and the headphones got so hot that they quit working. I was able to hear a sound out of two of the plugs before the headphones were killed. I haven’t tried to plug in anything else yet.
I believe that I need to get something like the Make Noise XOA to bring everything to line level so I don’t fry anymore headphones.
http://makenoisemusic.com/modules/xoh
You don’t need a midi controller to make an oscillator work, and you don’t need a module to attenuate your signals — a pot will do that. Put several pots behind a panel and you have a passive attenuator module, and you can use that to safely listen to whatever the modules are putting out.
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I don’t know how to do this / set something like this up. When I find a stripboard layout for something like an attenuator it’s often followed up by posts from people saying the layout is incorrect or someone built it and it’s not working, etc… So if I can find a DIY attenuator to safely listen to signals then I’ll build it. Can you recommend one?
Do you have an audio interface for the computer?
