In order to download the signal, you need to also tinker with the frequencies, to get the yellow numbers as close to 100 as possible. (Usually, try to at least get them to 99, imo.) To do this, you have two, horizontal rows of knobs. You hold interact on these, and use the mousewheel to change which way the frequencies go, either negatively or positively.
With the top, it'll go either left or right, depending on which. When you get close to the spot you are meant to get to, the yellow number will go up, and go down if you get further from it. If the frequency goes in a full circle, and the yellow number isn't affected, you need to hit the red switch that'll be to the left of the top, horizontal row. This will change its method, and require you to do so, until you find the right frequency. Repeat, until the yellow number is affected, then get it as close to 100 as possible.
With the bottom row, it is a lot simpler. It goes between 0 to 1000, and between those numbers, you'll find the area you need to be close to, to affect the yellow number. Simply find the number, and then that's it. When you get both of these methods close to 100, the signal will begin to download.