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This is my first time designing a PCB, and because it is part of a project at uni I have the intention of manufacturing it afterwards. The circuit itself is a voltage-controlled oscillator designed by Ray Wilson MFOS:

Page 1: http://www.musicfromouterspace.com/analogsynth_new/VCO20120618REV0/pdf/vco20120615wsoic_page_1_assembly.pdf

Page 2: http://www.musicfromouterspace.com/analogsynth_new/VCO20120618REV0/pdf/vco20120615wsoic_page_2_assembly.pdf

The website is full of great info and resources, including the PCB layout that he himself used. To speed the process of my design up I have mimicked his assembly layout using the PCB design tool that comes with TINA, but through differences of software, there are differences in the final results.

This may be a silly question, but my concern comes from the the grounding issues that may (or may not) arise. On Ray's PCB there is a ground pin which I imagine is the bridge between the power supply and ground plane?:Highlighted in yellow

And on my PCB i've used two pin headers, so there is effectively two ground pins, and am hesitant in how to connect ground properly from my power supply to the PCB using this particular set up:Highlighted in blue

The PCB started as two layer and I've added a ground and power plane, but how do I ensure that ground is connected properly at the VS1 and VS2 power supply headers after manufacture? Would I short the two ground pins and proceed to hook up the power supply, or use banana jacks to to hook both ground pins up accordingly? I apologize for this rookie question, and if any more info is needed let me know! Here's an un-routed 3D view of my PCB design (ground pins of power supply headers circled in blue):gnd pins in blue

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    \$\begingroup\$ You should give that board back to the Museum of Ancient Technology. This is not how things are done today, or have been for 15-20 years. You should really be learning modern methods, not using ancient thru hole parts like this. Prospective employers will laugh at this. How you lay out this board with its archaic parts is irrelevant to any future product you might try to create. \$\endgroup\$ Nov 30 '14 at 13:00
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I would connect both pins directly to the ground plane. You want the electric potential at these points to be as similar as possible, which means you should connect them with the lowest impedance you can. That's the ground plane.

Remember, ground isn't magic. It's just a net like any other. The charges moving in your circuit don't even know what "ground" is. Also remember that the ground current is equal to the supply current. Think about where the currents flow in your circuit, and what those currents will do when the ground connection has inductance and resistance. Usually you want ground to be as much the same voltage everywhere as possible, which means minimizing inductance and resistance at every opportunity.

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The original circuit has 3 connections: +12V, Ground, and -12V. To ensure a low resistance at the connector, each one is using 2 pins in parallel. So, as mentioned by @PhilFrost you connect both pins directly to the ground plane.

I am more concerned by the way 2 power supply pins have gone missing. The -12V line from R60 (SINBIAS) seems to go to the lower right pin. Where has the +12V line gone?
Are you going to have some sort of key connector here, to prevent accidentally installing the power connector the wrong way around?

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