You're telling me. I lose brain cells every time I have to look up or mention that the same visual mods that cost capacity when installed in a cybereye take up no room when you install them in a pair of contacts.

Ouch. There went a couple more.

...for contacts, I usually add the availability of enhancements to that of the contacts and limit the total to the Chargen availability cap. Same with glasses and the monocle. Goggles and helmet visors are much more robust and therefore should be able to accept a wide array of enhancements.

What they really needed to do is designate a capacity rating for visual and audio gear as they did with Cybereyes & ears and use the same ratings for the various improvements.

Isn't it how it's supposed to be done ?

The first and last idea there seem to conflict.

Do I simply roll Sensor in order to detect radio signals, without purchasing the Radio Signal Scanner? If I do have to purchase a Radio Signal Scanner, don't I also have to purchase a Camera and Microphone and fit them in my sensor package, as the FAQ suggests? If my drone only has a sensor package capacity of 1, does that mean I have to choose between a Camera and a Radio Signal Scanner? If I do, and I pick the latter, how does my drone even navigate?

Just some questions to stir dialog.

The sensor capabilities can always be defined as the plot needs.

You can start with them undefined and they become defined when you use it or when it really matters. Or you can define it to begin with, and be stuck with that.

So if the sensor exact attributes aren't defined to begin with,a nd it matters at some point during the game, well define them then, and that's what that particular drone sensors work as from that point on.

If you want to know when buying the drone how the sensor works, then buy it that way, and from that point on it uses that particular attribute for sensors.

Both ways work for me. Neither is wrong as far as I'm concerned.

Almost. That's exactly how it's done during character creation.
The problem is after character creation they can theoretically get their hands on an arbitrarily high availability. The bigger problem is that with a permit (or sometimes no permit, depending on the configuration) they can get these contact lenses with no regard for availability whatsoever, because availability does not apply to legal purchases.
Putting an absolute hard-cap on the availability of contacts post-chargen is the same fix that I use as well. You can use the same rule with goggles if you want, but since goggles have a base availability lower than contacts, they can naturally fit more toys.

If you check the listing for "camera" on p.325 it indicates that cameras capture still photos, video, or trideo and sound. So a basic camera is more than enough to operate a drone.

Granted that eliminates the need for a microphone, but that wasn't the nature of my question. In fact, it then becomes, can a drone operate without using one of its sensor package capacity for a "Camera"?

Unfortunately this advice isn't of much help to those of us that are looking for a standardized homogeneous system to incorporate into our games, based upon the rules we currently have. I think I agree the most with Redjack's solution, even though it admittedly isn't the best solution. The best solution is most hopefully going to be seen in an errata or Arsenal when there is a clarification.