How to control transparancy?

So, I'm learning Fusion, and was hoping someone could give me a quick answer to what seems like should be a simple question. I want to control the transparency of the output of either a merge node or a transform node, so I can fade it in and out. How do I do this? I've been looking for a way for a while and haven't figured it out. I've not found anything in the manuals either. A pointer would be appreciated!

All you need to do is adjust the blend in the merge. It will 'dissolve' the foreground.

You should consider going through these quick tutorials as well. These will cover all the basics for you.

https://www.blackmagicdesign.com/produc ... n/training

In general that helps, but in this case, there is no merge. What I want to fade in is the input to a background of a merge, and the output node that I want to fade is a DVE. The blend on that doesn't fade the output in and out, it fades the motion effects in and out, causing the output to jump to it's new location. How do I just fade the output of the DVE? Or do I have to create a transparent background PNG image to use as the background image to a merge, just so I can have the output of the DVE be the foreground image to a merge so I can fade it? Seems like there should be a simpler way.

And yes, I have watched the tutorial videos, but thanks for the pointer to them.