Conditional Logic to display Captcha?

I've just setup my first Gravity Form and it's currently got 4 fields (in this order):

Name:
Email:
Phone:
Captcha (Really Simple Captcha):

Then the Submit Button. Not sure if this is important, but all fields are required.

I'd like the Captcha field to be hidden, but then display after someone enters their Phone Number.

Is this possible?

If it's easier, I suppose that I could have it display after their name and/or email is entered as well, I just figured that since the phone is the last field before pressing the submit button that the conditional field might as well go there.

Thanks for your replies,
Aaron

Hi David,

Thanks for your reply.

Yes, I did try and play with the conditional logic in the form settings, but I wasn't sure what to do.

The first drop down shows 3 fields, but they are all blank. I'm assuming because I left the "Field Label" empty in the Name, Email and Phone fields.

Even so, I picked the 3rd empty dropdown, hoping it would be the phone number, and then I changed the second dropdown to "greater than", and I was going to put like 8 digits or something, just to be sure a valid phone number was actually entered, but I don't know how to express that in the "Enter a value" field.

Any help here is much appreciated.

Thanks,
Aaron

I've searched and searched (through documentation and forum), but I just can't find a user-friendly list of conditional logic commands to use.

Could somebody please provide me with one?

Thanks,
Aaron