You are using the Connect tool to connect up sockets and although the selection higlighting tells you there is a Circuit there it seems to be invisible. Here’s what’s happening.
You are seeing this
If you try creating a new drawing from the standard template connections look good. So there’s the clue – it’s in your document.
Check Class visibilities
Click on this button in the top-left corner of your document.
Scroll down the class list to Sys-Circuits. You’ll see a set of classes all beginning with Sys-Circuits- followed by the signal type. This is how you can define the look of Circuits for each type of signal on your drawing.
Ah there’s the culprit! Look at Sys-Circuits-HDV. The Pen Color is blank, the line style is blank and the line thickness is set to zero. No chance of seeing that !!! Also the Use at Creation is unchecked – but that’s not important, the class attributes are applied anyway. Now let’s see how to fix it. Go ahead and double-click the class name, or select the class Sys-Circuits-HDV in the list and click the Edit.. button.
Fix Class Attributes
The Pen Style was None so nothing gets drawn. Set it to Solid for a normal solid line and pick a colour. Or if you want to experiment you can try Pattern or Line Type.
As long as the Line Thickness is zero the line will be invisible – so set that to a value that suits you.
Click on OK to exit , and …
Circuits are visible again
connectCAD gives you fine control over the look of your drawings including the ability to hide components as well. That can be handy at times.